๐Ÿ”ฅ Complete Class 12 Chemistry Formulas Chapter-wise | All Reactions, Tricks & Notes for Boards & NEET/JEE

๐Ÿ”ฐ **Complete Class 12 Chemistry Formulas – Chapter-wise with Reactions, Tricks & Short Notes**

๐Ÿ“š Are you a Class 12 student preparing for CBSE, AHSEC, or any competitive exam like NEET, JEE, CUET, etc.?  

Then this post is your ultimate one-stop solution!

We have compiled **all chapters of Class 12 Chemistry** with complete **formulas, reactions, tricks, and quick revision notes** in one place — all presented in **simple code format**, perfect for fast memorization and blogging. From **Solid State** to **Chemistry in Everyday Life**, every formula is arranged chapter-wise for easy navigation and maximum clarity.


Whether you’re revising for board exams or building a strong base for competitive entrance tests, these formulas will help you save time, score full marks, and build conceptual confidence.


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๐Ÿ’ฅ **What You’ll Get in This Post:**

- ✅ All 15 Chapters of Class 12 Chemistry (Physical, Inorganic & Organic)

- ✅ Formulas + Mechanisms + Short Tricks

- ✅ Reactions with Equations & Examples

- ✅ Distinguishing Tests & Important Keywords

- ✅ Ready for Direct Use in Blogger or HTML post (code format)


๐Ÿงช **List of Covered Chapters:**

1. Solid State  

2. Solutions  

3. Electrochemistry  

4. Chemical Kinetics  

5. Surface Chemistry  

6. The p-Block Elements  

7. The d- and f-Block Elements  

8. Coordination Compounds  

9. Haloalkanes and Haloarenes  

10. Alcohols, Phenols and Ethers  

11. Aldehydes, Ketones and Carboxylic Acids  

12. Amines  

13. Biomolecules  

14. Polymers  

15. Chemistry in Everyday Life


๐Ÿ“Œ Bookmark this page, share it with your friends, and master Chemistry with confidence.


๐Ÿš€ **Powered by Vidya Unnati Academy – Learn Smart. Score Maximum.**

๐Ÿ”น CHAPTER 1: SOLUTIONS – Important Formulas

๐Ÿ“˜ Basic Concepts:

- Solution = Solute + Solvent

- Homogeneous mixture of two or more substances


๐Ÿ“Œ Mass Percentage (% w/w):

= (Mass of solute / Mass of solution) × 100


๐Ÿ“Œ Volume Percentage (% v/v):

= (Volume of solute / Volume of solution) × 100


๐Ÿ“Œ Mole Fraction (X):

= moles of component / total moles of all components

= n₁ / (n₁ + n₂)


๐Ÿ“Œ Molarity (M):

= (Moles of solute) / (Volume of solution in Litres)


๐Ÿ“Œ Molality (m):

= (Moles of solute) / (Mass of solvent in kg)


๐Ÿ“Œ Normality (N):

= (Gram equivalent of solute) / (Volume of solution in litres)


๐Ÿ“Œ Parts per million (ppm):

= (Mass of solute / Mass of solution) × 10⁶


๐Ÿ“Œ Mole Fraction Relation:

XA + XB = 1


๐Ÿ“Œ Dilution Formula:

M₁V₁ = M₂V₂


๐Ÿ”น Raoult’s Law:

P_A = X_A × P⁰_A

P_total = P_A + P_B = X_A·P⁰_A + X_B·P⁰_B


๐Ÿ”น Colligative Properties:


1. Relative Lowering of Vapour Pressure:

(ฮ”P / P⁰) = X_solute


2. Elevation in Boiling Point:

ฮ”T_b = K_b × m


3. Depression in Freezing Point:

ฮ”T_f = K_f × m


4. Osmotic Pressure:

ฯ€ = C × R × T

   = (n/V) × R × T


๐Ÿ”น van’t Hoff Factor (i):

i = observed colligative property / calculated colligative property


๐Ÿ”น Abnormal Molar Mass:

Corrected molar mass = (normal colligative formula) / i


๐Ÿง  Notes:

✔ Molarity changes with temperature

✔ Molality is temperature independent

✔ Colligative properties depend on number of particles, not nature

✔ Electrolytes dissociate → i > 1

✔ Associating compounds → i < 1


๐Ÿ“Œ Units to Remember:

- Molarity: mol/L

- Molality: mol/kg

- R: 0.0821 L·atm/mol·K or 8.314 J/mol·K

๐Ÿ”น CHAPTER 2: ELECTROCHEMISTRY – Important Formulas


๐Ÿ“˜ Basic Terms:

- Electrochemistry deals with the relation between electricity and chemical reactions.

- Two main types of cells:

  1. Electrolytic Cell – Uses electrical energy to drive a chemical reaction.

  2. Galvanic Cell (Voltaic Cell) – Produces electrical energy from a spontaneous redox reaction.


────────────────────────

๐Ÿ“Œ Ohm’s Law:

V = I × R

Where:  

V = Voltage (Volts)  

I = Current (Amperes)  

R = Resistance (Ohms)


๐Ÿ“Œ Resistance of a conductor:

R = ฯ × (l / A)

Where:  

ฯ = resistivity (ohm·m),  

l = length (m),  

A = area of cross-section (m²)


๐Ÿ“Œ Conductance (G):

G = 1 / R  

Unit: Siemens (S)


๐Ÿ“Œ Specific Conductivity (ฮบ or kappa):

ฮบ = G × (l / A)

or  

ฮบ = 1 / ฯ  

Unit: S·m⁻¹ or S·cm⁻¹


๐Ÿ“Œ Molar Conductivity (ฮ›โ‚˜):

ฮ›โ‚˜ = (ฮบ × 1000) / C  

Where:  

C = concentration in mol/m³ or mol/L  

Unit: S·cm²/mol


๐Ÿ“Œ Variation of ฮ›โ‚˜ with dilution:

- For strong electrolytes: Increases slowly and approaches a limiting value (ฮ›°โ‚˜).

- For weak electrolytes: Increases sharply.


๐Ÿ“Œ Kohlrausch’s Law:

ฮ›°โ‚˜ (AB) = ฮ›°โ‚˜ (A⁺) + ฮ›°โ‚˜ (B⁻)


────────────────────────

๐Ÿ”‹ Electrochemical Cell Formulas:


๐Ÿ“Œ Cell Notation:

Zn | Zn²⁺ (1M) || Cu²⁺ (1M) | Cu  

(Anode on left, cathode on right)


๐Ÿ“Œ EMF of the cell:

E°cell = E°cathode – E°anode


๐Ÿ“Œ Gibbs Free Energy:

ฮ”G° = –nFE°cell  

Where:  

n = number of electrons transferred  

F = Faraday = 96500 C/mol


๐Ÿ“Œ Nernst Equation:

E_cell = E°cell – (0.0591 / n) × log(Q)  

Where Q = [products]/[reactants]


✔ For a general redox reaction:  

aA + bB ⇌ cC + dD  

Q = ([C]^c × [D]^d) / ([A]^a × [B]^b)


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๐Ÿ“Œ Faraday’s Laws of Electrolysis:


1. **First Law:**

Mass (m) ∝ Quantity of electricity (Q)  

m = (Z × Q) = (Z × I × t)  

Where:  

Z = electrochemical equivalent  

I = current (A), t = time (s)


2. **Second Law:**

When same current passed through different electrolytes,  

mass deposited ∝ equivalent weight


๐Ÿ“Œ Equivalent weight:

E = (Molecular weight) / (n electrons involved)


๐Ÿ“Œ Charge required for 1 mole of electron:

1 Faraday (F) = 96500 Coulombs


────────────────────────

๐Ÿง  Important Units and Constants:

- R = 8.314 J/mol·K  

- F = 96500 C/mol  

- 1 Volt = 1 Joule/Coulomb  

- 1 ampere = 1 C/s


────────────────────────

๐Ÿ“Œ Conductivity Order (approx):

Strong electrolyte > Weak electrolyte > Nonelectrolyte


๐Ÿ“Œ Applications:

- Batteries (Lead-acid, Lithium-ion)  

- Electroplating  

- Fuel cells  

- Corrosion (electrochemical process)

๐Ÿ”น CHAPTER 3: CHEMICAL KINETICS – Important Formulas


๐Ÿ“˜ Introduction:

Chemical Kinetics deals with the **rate of chemical reactions** and the **factors** that affect them.


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๐Ÿ“Œ Average Rate of Reaction:

= (Change in concentration) / (Change in time)  

Rate = –ฮ”[R]/ฮ”t = +ฮ”[P]/ฮ”t  

Unit: mol L⁻¹ s⁻¹


๐Ÿ“Œ Instantaneous Rate:

Rate = –d[R]/dt = +d[P]/dt  

๐Ÿ‘‰ Derivative of concentration w.r.t. time.


๐Ÿ“Œ Rate Law (Rate Expression):

Rate = k[A]^x[B]^y  

Where:  

k = rate constant  

x, y = order with respect to A and B


๐Ÿ“Œ Overall Order of Reaction:

= x + y  

(It can be zero, fractional, or whole number)


๐Ÿ“Œ Units of Rate Constant (k):

Depends on overall order (n) of reaction:  

k = (mol)¹⁻โฟ · Lโฟ⁻¹ · s⁻¹


Examples:

- Zero Order: k = mol L⁻¹ s⁻¹  

- First Order: k = s⁻¹  

- Second Order: k = L mol⁻¹ s⁻¹


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๐Ÿ“Œ Integrated Rate Equations:


๐Ÿ”น **Zero Order Reaction**:  

Rate = k  

[A] = [A]₀ – kt  

t½ = [A]₀ / (2k)


๐Ÿ”น **First Order Reaction**:  

Rate = k[A]  

ln([A]₀/[A]) = kt  

OR  

k = (2.303 / t) × log([A]₀ / [A])  

t½ = 0.693 / k  

๐Ÿง  Half-life is independent of initial concentration.


๐Ÿ”น **Second Order Reaction**:  

Rate = k[A]²  

1/[A] = 1/[A]₀ + kt  

t½ = 1 / (k[A]₀)


────────────────────────

๐Ÿ“Œ Arrhenius Equation:

k = A · e^(–Ea / RT)  

Where:  

k = rate constant  

A = frequency factor  

Ea = activation energy  

R = gas constant  

T = temperature in Kelvin


๐Ÿ“Œ Logarithmic Form of Arrhenius Equation:

log k = log A – (Ea / 2.303RT)


๐Ÿ“Œ Two-Temperature Form:

log(k₂/k₁) = (Ea / 2.303R) × [(T₂ – T₁) / (T₁T₂)]


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๐Ÿง  Reaction Mechanism:

- A sequence of elementary steps

- **Rate-determining step** = slowest step of the mechanism

- Molecularity: number of molecules involved in an elementary step


๐Ÿ“Œ Molecularity ≠ Order  

๐Ÿ‘‰ Molecularity is always whole number, never zero or fractional.


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๐Ÿ“Œ Graphical Analysis:

- First Order: ln[A] vs time → straight line (–ve slope)

- Zero Order: [A] vs time → straight line

- Second Order: 1/[A] vs time → straight line


๐Ÿ“Œ Half-life Summary:

| Order | t½ formula | Depends on [A]₀? |

|-------|----------------------|------------------|

| 0 | [A]₀ / 2k | Yes |

| 1 | 0.693 / k | No |

| 2 | 1 / (k × [A]₀) | Yes |


๐Ÿ“Œ Activation Energy Unit:  

Usually in J/mol or kJ/mol


────────────────────────

๐Ÿง  Tricks to Remember:

✔ Zero Order → constant rate  

✔ First Order → radioactive decay, t½ = 0.693/k  

✔ Increase in temperature → increases k exponentially  

✔ Higher Ea → slower reaction  

✔ Catalyst lowers activation energy


๐Ÿ”น CHAPTER 4: SURFACE CHEMISTRY – Important Formulas & Concepts


๐Ÿ“˜ Introduction:

Surface chemistry deals with phenomena that occur at the surface or interface of two phases, especially **adsorption, catalysis**, and **colloids**.


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๐Ÿ”ธ ADSORPTION


๐Ÿ“Œ Adsorption:

The accumulation of molecules on the surface of a solid or liquid.


๐Ÿ“Œ Types of Adsorption:

1. **Physisorption (Physical adsorption)**  

   - Weak van der Waals forces  

   - Low heat of adsorption (20–40 kJ/mol)  

   - Multilayer  

   - Reversible  


2. **Chemisorption (Chemical adsorption)**  

   - Strong chemical bonds  

   - High heat of adsorption (80–240 kJ/mol)  

   - Monolayer  

   - Irreversible  


๐Ÿ“Œ Freundlich Adsorption Isotherm:

\[

\frac{x}{m} = k P^{1/n}

\]  

Where:  

x = mass of gas adsorbed  

m = mass of adsorbent  

P = pressure  

k, n = constants (n > 1)  

๐Ÿง  log form:

\[

\log\left(\frac{x}{m}\right) = \log k + \frac{1}{n} \log P

\]


๐Ÿ“Œ Langmuir Adsorption Isotherm:

\[

\theta = \frac{kP}{1 + kP}

\]  

Where:

- \( \theta \) = fraction of surface covered  

- k = equilibrium constant  

- P = pressure


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๐Ÿ”ธ CATALYSIS


๐Ÿ“Œ Catalyst:

A substance that increases the rate of a reaction without itself undergoing any permanent chemical change.


๐Ÿ“Œ Types:

1. **Homogeneous Catalysis** – Catalyst in same phase  

2. **Heterogeneous Catalysis** – Catalyst in different phase


๐Ÿ“Œ Characteristics of Catalyst:

- Effective in small quantity  

- Does not initiate reaction  

- Specific in nature  

- Unchanged at the end of reaction  

- Affected by promoters and poisons


๐Ÿ“Œ Examples:

- Haber Process: N₂ + 3H₂ → 2NH₃ (Fe catalyst)  

- Contact Process: SO₂ + O₂ → SO₃ (V₂O₅ catalyst)


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๐Ÿ”ธ COLLOIDS


๐Ÿ“Œ Colloid:

A heterogeneous system in which the dispersed phase particles (1–1000 nm) are spread throughout the dispersion medium.


๐Ÿ“Œ Types of Colloids (Based on Dispersion Phase & Medium):


| Dispersed Phase | Dispersion Medium | Type of Colloid | Example |

|------------------|--------------------|------------------|----------------|

| Liquid | Gas | Aerosol | Fog, mist |

| Gas | Liquid | Foam | Froth, whipped cream |

| Solid | Liquid | Sol | Paints, inks |

| Liquid | Solid | Gel | Cheese, butter |


๐Ÿ“Œ Tyndall Effect:

Scattering of light by colloidal particles.


๐Ÿ“Œ Brownian Movement:

Random zig-zag motion of colloidal particles due to collisions.


๐Ÿ“Œ Electrophoresis:

Movement of colloidal particles under an electric field.


๐Ÿ“Œ Coagulation:

Removal of colloidal stability (precipitation of colloid)


๐Ÿ“Œ Hardy–Schulze Rule:

Greater the valency of the ion, greater is its power to coagulate colloid.


๐Ÿ“Œ Gold Number:

Minimum amount of protective colloid (in mg) required to prevent coagulation of 10 mL of gold sol by NaCl.


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๐Ÿง  Important Notes:

✔ Adsorption ≠ Absorption  

✔ Physical Adsorption → low temp, weak bond  

✔ Chemical Adsorption → high temp, strong bond  

✔ Colloids are stable due to charge  

✔ Lyophilic sols are more stable than lyophobic sols


๐Ÿ”น CHAPTER 5: PRINCIPLES & PROCESSES OF ISOLATION OF ELEMENTS – Important Formulas & Concepts


๐Ÿ“˜ Introduction:

Metallurgy is the process of extraction of metals from their ores and refining them for use.


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๐Ÿ”ธ IMPORTANT TERMS


๐Ÿ“Œ Mineral:

A naturally occurring substance containing metal, associated with impurities.


๐Ÿ“Œ Ore:

A mineral from which metal can be extracted economically.


๐Ÿ“Œ Gangue:

Impurities like sand, clay present in the ore.


๐Ÿ“Œ Flux:

A substance added to remove gangue by forming a fusible mass called slag.


๐Ÿ“Œ Slag:

Fusible product formed by reaction of flux with gangue.

\[

\text{Gangue} + \text{Flux} → \text{Slag}

\]


────────────────────────

๐Ÿ”ธ IMPORTANT STEPS IN METALLURGY


1. **Concentration of Ore** (Removal of gangue)  

   - Hydraulic washing  

   - Magnetic separation  

   - Froth flotation (for sulphide ores)


2. **Calcination and Roasting**

- **Calcination** (in limited or no air):

  \[

  \text{CaCO}_3 → \text{CaO} + \text{CO}_2

  \]

- **Roasting** (in excess air):

  \[

  2ZnS + 3O₂ → 2ZnO + 2SO₂

  \]


3. **Reduction (Smelting):**

Metal oxides → metal by reduction using:  

- Carbon (C)  

- Aluminium (Al) – *Aluminothermic process*

  \[

  Cr₂O₃ + 2Al → 2Cr + Al₂O₃

  \]


4. **Electrolytic Reduction:**

Used for highly reactive metals (Na, Mg, Al)

- Electrolysis of molten ore


5. **Refining (Purification):**

✔ Electrolytic refining:  

Anode = impure metal  

Cathode = pure metal  

Electrolyte = metal salt solution  

Example:

\[

\text{Anode:} Cu → Cu²⁺ + 2e⁻  

\text{Cathode:} Cu²⁺ + 2e⁻ → Cu

\]


✔ Zone refining (for Si, Ge):  

Based on differing solubility of impurities.


✔ Vapour phase refining:

- Mond’s Process (Ni):  

  \[

  Ni + 4CO → Ni(CO)₄ (g) → Ni + 4CO

  \]

- van Arkel process (Zr, Ti):  

  \[

  Zr + 2I₂ → ZrI₄ → Zr + 2I₂

  \]


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๐Ÿ”ธ THERMODYNAMIC CONSIDERATIONS


๐Ÿ“Œ Gibbs Free Energy:

\[

\Delta G = \Delta H - T\Delta S

\]  

If ฮ”G < 0 → reaction is spontaneous


๐Ÿ“Œ Ellingham Diagram:

Graph of ฮ”G° vs Temperature for reduction reactions  

✔ Lower the line on the diagram → more stable the oxide  

✔ A metal can reduce another’s oxide if its line lies below


๐Ÿ“Œ Feasibility of Reduction:

A metal (M₁) can reduce the oxide of another metal (M₂O) if:  

\[

\Delta G^\circ_{\text{M₁ → M₁O}} < \Delta G^\circ_{\text{M₂ → M₂O}}

\]


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๐Ÿ”ธ IMPORTANT FORMULAS


๐Ÿ“Œ % Purity of metal in ore:

\[

\% \text{Purity} = \left( \frac{\text{Mass of pure metal}}{\text{Mass of ore sample}} \right) × 100

\]


๐Ÿ“Œ Mass of metal extracted:

\[

\text{Mass} = \text{Number of moles} × \text{Molar mass}

\]


๐Ÿ“Œ Faraday’s Law (for electrolytic reduction):

\[

\text{w} = \frac{E \cdot I \cdot t}{96500}

\]  

Where:  

w = mass deposited  

E = equivalent weight  

I = current (A)  

t = time (s)


────────────────────────

๐Ÿง  Quick Summary:


✔ Sulphide ores → Roasting  

✔ Carbonates → Calcination  

✔ Highly reactive metals → Electrolysis  

✔ Less reactive metals → Reduction by C or CO  

✔ Very reactive metals → Electrolysis of molten salts


๐Ÿ”น CHAPTER 6: THE p-BLOCK ELEMENTS – Key Concepts, Trends & Reactions


๐Ÿ“˜ Introduction:

- Group 15 to Group 18 elements are part of the p-block in Class 12.

- Includes: N, P, As, Sb, Bi (Group 15), O, S, Se, Te, Po (Group 16), F, Cl, Br, I (Group 17 – Halogens), and Noble Gases (Group 18).


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๐Ÿ”ธ GROUP 15 ELEMENTS (NITROGEN FAMILY)


๐Ÿ“Œ General Configuration: ns² np³  

๐Ÿ“Œ Oxidation States: –3, +3, +5  

๐Ÿ“Œ Allotropy:  

- P → White, red, black phosphorus


๐Ÿ“Œ Key Compounds:

1. **Ammonia (NH₃):**  

   Structure: Trigonal pyramidal  

   H-bonding, high boiling point


2. **Nitric Acid (HNO₃):**  

   - Strong oxidizing agent  

   - Reaction with copper:

     \[

     Cu + 4HNO₃ → Cu(NO₃)₂ + 2NO₂ + 2H₂O

     \]


3. **Oxides of Nitrogen:**  

   N₂O, NO, NO₂, N₂O₃, N₂O₅  

   - Acidic character increases with oxidation number


๐Ÿ“Œ Anomalous Behaviour of Nitrogen:

- Small size, high electronegativity  

- Ability to form pฯ€–pฯ€ bonds  

- Forms triple bond in N₂


────────────────────────

๐Ÿ”ธ GROUP 16 ELEMENTS (OXYGEN FAMILY)


๐Ÿ“Œ General Configuration: ns² np⁴  

๐Ÿ“Œ Oxidation States: –2, +2, +4, +6


๐Ÿ“Œ Oxygen:

- Allotropy: O₂ (dioxygen), O₃ (ozone)  

- O₂ + O → O₃ (ozone formation)  

- Ozone is powerful oxidant


๐Ÿ“Œ Sulphur Compounds:

1. **Sulphur Dioxide (SO₂):**  

   \[

   S + O₂ → SO₂  

   SO₂ + H₂O → H₂SO₃ (Sulphurous acid)

   \]


2. **Sulphuric Acid (H₂SO₄):**  

   - Dibasic, strong acid  

   - Acts as dehydrating & oxidizing agent


๐Ÿ“Œ Oxoacids of Sulphur:

- H₂SO₃, H₂SO₄, H₂S₂O₇ etc.


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๐Ÿ”ธ GROUP 17 ELEMENTS (HALOGENS)


๐Ÿ“Œ General Configuration: ns² np⁵  

๐Ÿ“Œ Highly reactive non-metals  

๐Ÿ“Œ Oxidation States: –1, +1, +3, +5, +7  

๐Ÿ“Œ Reactivity: F > Cl > Br > I  

๐Ÿ“Œ Acidity of HX: HF < HCl < HBr < HI


๐Ÿ“Œ Key Reactions:

- Halogen + Alkali (Cold):

  \[

  Cl₂ + 2NaOH → NaCl + NaOCl + H₂O

  \]

- Halogen + Alkali (Hot):

  \[

  3Cl₂ + 6NaOH → 5NaCl + NaClO₃ + 3H₂O

  \]


๐Ÿ“Œ Interhalogen Compounds:  

General Formula: AXโ‚™ (n = 1, 3, 5, 7)


๐Ÿ“Œ Structure Examples:

- ClF₃ → T-shaped  

- IF₇ → Pentagonal bipyramidal


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๐Ÿ”ธ GROUP 18 ELEMENTS (NOBLE GASES)


๐Ÿ“Œ Configuration: ns² np⁶  

๐Ÿ“Œ Monoatomic, inert  

๐Ÿ“Œ Uses:  

- He: balloons, cryogenics  

- Ne: advertisement signs  

- Ar: inert atmosphere in metallurgy  

- Xe: lighting, compound formation


๐Ÿ“Œ Important Compounds:

- XeF₂, XeF₄, XeF₆ → Fluorides of Xenon


๐Ÿ“Œ Hybridization & Structure:

- XeF₂ → Linear (sp³d)  

- XeF₄ → Square planar (sp³d²)  

- XeF₆ → Distorted octahedral


๐Ÿ“Œ Key Reaction Example:

\[

Xe + F₂ → XeF₂ (under high temp and pressure)

\]


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๐Ÿง  Trends Summary Across p-Block:


| Property | Top to Bottom | Left to Right (Group 15 → 18) |

|------------------|---------------|-------------------------------|

| Atomic Radius | Increases | Decreases |

| Ionization Energy| Decreases | Increases |

| Electronegativity| Decreases | Increases |

| Reactivity | Variable | Non-metallic → Inert |


๐Ÿ“Œ Tips:

✔ F is most reactive non-metal  

✔ N₂ is triple bonded, inert  

✔ NH₃ is basic, pyramidal  

✔ HNO₃, H₂SO₄ = strong oxidizing agents  

✔ Noble gases form very few compounds (only Xe and Kr)


๐Ÿ”น CHAPTER 7: THE d- AND f-BLOCK ELEMENTS – Key Formulas, Properties & Trends


๐Ÿ“˜ Introduction:

- d-Block → Transition Elements (Groups 3–12)

- f-Block → Inner-Transition Elements (Lanthanides and Actinides)


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๐Ÿ”ธ d-BLOCK ELEMENTS


๐Ÿ“Œ General Configuration:

(n–1)d¹⁻¹⁰ ns¹⁻²


๐Ÿ“Œ Characteristics of Transition Elements:

✔ Variable oxidation states  

✔ Formation of colored ions  

✔ Catalytic properties  

✔ Formation of complex compounds  

✔ High melting and boiling points  

✔ Paramagnetic due to unpaired d-electrons


๐Ÿ“Œ Common Oxidation States:

- Sc → +3  

- Ti → +2, +3, +4  

- Fe → +2, +3  

- Cu → +1, +2  

- Mn → +2 to +7 (maximum range)


๐Ÿ“Œ Magnetic Moment Formula:

\[

\mu = \sqrt{n(n+2)} \text{ BM}

\]  

Where:  

n = number of unpaired electrons  

BM = Bohr Magneton


๐Ÿ“Œ Color of Compounds:

Due to **d–d transitions** of unpaired electrons in the presence of ligands (Crystal Field Theory)


๐Ÿ“Œ Catalytic Properties:

Due to variable oxidation states and surface activity  

e.g., Fe in Haber Process, V₂O₅ in Contact Process


๐Ÿ“Œ Alloy Formation:

- Cu, Ni, Zn form strong alloys due to similar atomic size


๐Ÿ“Œ Interstitial Compounds:

- Transition metals form compounds with small atoms (H, B, C, N)  

  → e.g., Fe₃C (cementite)


๐Ÿ“Œ Complex Formation:

- Due to small size, high charge, and availability of d-orbitals  

  → Form coordination compounds like [Fe(CN)₆]³⁻


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๐Ÿ”ธ f-BLOCK ELEMENTS


๐Ÿ“Œ General Configuration:

- Lanthanides: [Xe] 4f¹–¹⁴ 5d⁰⁻¹ 6s²  

- Actinides: [Rn] 5f¹–¹⁴ 6d⁰⁻¹ 7s²


๐Ÿ“Œ Characteristics of Lanthanides:

✔ +3 oxidation state is most common  

✔ Slight variation in atomic size = **Lanthanide contraction**  

✔ Form colored ions  

✔ Show paramagnetism


๐Ÿ“Œ Lanthanide Contraction:

- Steady decrease in atomic/ionic radii across the series due to poor shielding of 4f electrons  

๐Ÿ‘‰ Results in:  

  – Similarity between Zr & Hf, Nb & Ta


๐Ÿ“Œ Consequences:

- Poor separation of lanthanides  

- Higher density & hardness of later members


๐Ÿ“Œ Actinides:

✔ Radioactive  

✔ Variable oxidation states (+3 to +6)  

✔ Greater tendency to form complexes than lanthanides


────────────────────────

๐Ÿ”ธ TRENDS IN PROPERTIES


๐Ÿ“Œ Melting & Boiling Point:

- High due to strong metallic bonding  

- Irregular trends due to electron configurations


๐Ÿ“Œ Ionization Enthalpy:

- Gradually increases across a series  

- Lower than s- and p-block due to d-orbitals


๐Ÿ“Œ Atomic & Ionic Radii:

- Decrease across period due to increasing nuclear charge  

- f-block → **Lanthanide contraction** observed


๐Ÿ“Œ Color and Magnetism:

- Due to presence of unpaired electrons in d- or f-orbitals


๐Ÿ“Œ Redox Reactions:

- Transition metals can exist in multiple oxidation states  

- Mn²⁺ → colorless, Mn⁷⁺ (in KMnO₄) → purple


────────────────────────

๐Ÿ“Œ Important Compounds & Uses:


- KMnO₄ (Potassium permanganate) – Oxidizing agent  

  \[

  MnO₄⁻ + 8H⁺ + 5e⁻ → Mn²⁺ + 4H₂O

  \]


- K₂Cr₂O₇ (Potassium dichromate) – Oxidizing agent  

  \[

  Cr₂O₇²⁻ + 14H⁺ + 6e⁻ → 2Cr³⁺ + 7H₂O

  \]


๐Ÿ“Œ Tests:

- KMnO₄ and K₂Cr₂O₇ used in redox titrations


────────────────────────

๐Ÿง  Summary Table:


| Element | Common Ox. States | Color | Magnetic? |

|---------|--------------------|---------------|------------|

| Sc | +3 | Colorless | Diamagnetic |

| Ti | +3, +4 | Violet, colorless | Paramagnetic |

| Fe | +2, +3 | Green, yellow | Paramagnetic |

| Cu | +1, +2 | Colorless, blue | Paramagnetic |

| Mn | +2 to +7 | Pink to purple | Paramagnetic |

| Zn | +2 | Colorless | Diamagnetic |


๐Ÿ“Œ f-block: All show complex behaviors, mainly studied qualitatively.


๐Ÿ”น CHAPTER 8: COORDINATION COMPOUNDS – Important Terms, Formulas & Structures


๐Ÿ“˜ Introduction:

Coordination compounds are formed by the **donation of lone pairs** from ligands to a central metal atom or ion, forming coordinate bonds.


────────────────────────

๐Ÿ”ธ KEY TERMS


๐Ÿ“Œ Coordination Entity:

[Co(NH₃)₆]³⁺ → Co³⁺ = central metal, NH₃ = ligands


๐Ÿ“Œ Ligand:

Ion or molecule that donates a pair of electrons to the metal.

- **Monodentate**: NH₃, Cl⁻, CN⁻  

- **Bidentate**: C₂O₄²⁻ (oxalate), ethylenediamine (en)  

- **Polydentate**: EDTA⁴⁻ (hexadentate)


๐Ÿ“Œ Coordination Number:

Number of ligand donor atoms bonded to central metal.  

e.g., [Fe(CN)₆]³⁻ → C.N. = 6


๐Ÿ“Œ Coordination Sphere:

Part enclosed in brackets [ ] → acts as a single unit


๐Ÿ“Œ Counter Ion:

Ion outside the coordination sphere, balancing the charge


๐Ÿ“Œ Chelation:

When a multidentate ligand forms a ring structure with metal.


────────────────────────

๐Ÿ”ธ NOMENCLATURE RULES


๐Ÿ“Œ Naming:

1. Name ligands first (alphabetical order), then metal  

2. Anionic ligands end in -o (Cl⁻ = chloro, CN⁻ = cyano)  

3. Neutral ligands – special names: NH₃ = ammine, H₂O = aqua  

4. Metal in cation → usual name  

   Metal in anion → ends with -ate (Ferrate, Cuprate)


๐Ÿ“Œ Examples:

- [Cr(NH₃)₄Cl₂]Cl → Tetraamminedichlorochromium(III) chloride  

- K₄[Fe(CN)₆] → Potassium hexacyanoferrate(II)


────────────────────────

๐Ÿ”ธ ISOMERISM


๐Ÿ“Œ Structural Isomerism:

- **Ionization Isomerism**: exchange of ligand and counter ion  

  e.g., [Co(NH₃)₅Br]SO₄ ↔ [Co(NH₃)₅SO₄]Br  

- **Hydrate Isomerism**: Water inside vs outside the sphere  

  e.g., [Cr(H₂O)₆]Cl₃, [Cr(H₂O)₅Cl]Cl₂·H₂O


๐Ÿ“Œ Stereoisomerism:

- **Geometrical**: cis/trans in square planar & octahedral  

  e.g., [Pt(NH₃)₂Cl₂]  

- **Optical**: non-superimposable mirror images  

  e.g., [Co(en)₃]³⁺ → shows optical isomerism


────────────────────────

๐Ÿ”ธ BONDING THEORIES


๐Ÿ“Œ Werner’s Theory:

- Primary valency = ionic  

- Secondary valency = coordinate bonds


๐Ÿ“Œ Valence Bond Theory (VBT):

- Explains hybridization and geometry  

- Inner orbital complex → low spin (d²sp³)  

- Outer orbital complex → high spin (sp³d²)


๐Ÿ“Œ Examples:

- [Fe(CN)₆]⁴⁻ → d²sp³ (low spin, diamagnetic)  

- [FeF₆]³⁻ → sp³d² (high spin, paramagnetic)


๐Ÿ“Œ Limitations of VBT:

❌ Doesn’t explain color, spectra, or exact magnetic moment


๐Ÿ“Œ Crystal Field Theory (CFT):

- Electrostatic interaction between metal ion & ligand  

- d-orbitals split in ligand field


๐Ÿ”ธ Octahedral Field Splitting:

- d-orbitals split into two groups:  

  t₂g (lower energy): d_xy, d_xz, d_yz  

  e_g (higher energy): d_z², d_x²–y²


๐Ÿ“Œ Crystal Field Splitting Energy:  

ฮ”₀ = Energy difference between e_g and t₂g levels


๐Ÿ“Œ Factors affecting ฮ”₀:

- Nature of metal ion  

- Oxidation state  

- Nature of ligand (Spectrochemical Series)


๐Ÿ“Œ Spectrochemical Series (increasing field strength):

I⁻ < Br⁻ < Cl⁻ < F⁻ < OH⁻ < H₂O < NH₃ < en < CN⁻ < CO


๐Ÿ“Œ CFSE (Crystal Field Stabilization Energy):

= (0.4 × no. of electrons in t₂g) – (0.6 × no. in e_g) × ฮ”₀


────────────────────────

๐Ÿ”ธ MAGNETIC MOMENT


๐Ÿ“Œ Magnetic Moment Formula:

\[

\mu = \sqrt{n(n+2)} \text{ BM}

\]  

Where n = number of unpaired electrons


๐Ÿ“Œ Diamagnetic = all electrons paired  

๐Ÿ“Œ Paramagnetic = unpaired electrons


────────────────────────

๐Ÿ”ธ IMPORTANT EXAMPLES


| Compound | Hybridization | Shape | Magnetic Nature |

|---------------------|---------------|--------------|------------------|

| [Co(NH₃)₆]³⁺ | d²sp³ | Octahedral | Diamagnetic |

| [Fe(CN)₆]⁴⁻ | d²sp³ | Octahedral | Diamagnetic |

| [FeF₆]³⁻ | sp³d² | Octahedral | Paramagnetic |

| [Ni(CO)₄] | sp³ | Tetrahedral | Diamagnetic |

| [NiCl₄]²⁻ | sp³ | Tetrahedral | Paramagnetic |

| [Pt(NH₃)₂Cl₂] | dsp² | Square planar| Diamagnetic |


๐Ÿ“Œ EDTA⁴⁻: Hexadentate ligand used in water softening and metal detoxification.


๐Ÿ“Œ Werner Complex Example:

[Co(NH₃)₆]Cl₃ → 3 Cl⁻ ions outside, total ions in solution = 4



๐Ÿ”น CHAPTER 9: HALOALKANES AND HALOARENES – Important Formulas, Reactions & Concepts


๐Ÿ“˜ Introduction:

- **Haloalkanes**: Alkyl group + halogen (R–X)  

- **Haloarenes**: Aryl group + halogen (Ar–X)


────────────────────────

๐Ÿ”ธ CLASSIFICATION


๐Ÿ“Œ Based on number of halogen atoms:

- Monohalo: CH₃Cl (methyl chloride)  

- Dihalo: CH₂Cl₂ (methylene chloride)  

- Trihalo: CHCl₃ (chloroform)  

- Tetrahalo: CCl₄ (carbon tetrachloride)


๐Ÿ“Œ Based on the type of carbon:

- **Primary** (1°): Halogen attached to 1° carbon (CH₃CH₂Cl)  

- **Secondary** (2°): CH₃CHClCH₃  

- **Tertiary** (3°): (CH₃)₃CCl


────────────────────────

๐Ÿ”ธ PREPARATION OF HALOALKANES


1. **From Alcohols:**

- ROH + HX → R–X + H₂O (with ZnCl₂ as catalyst)


2. **From Alkanes:**

- Free radical halogenation  

  CH₄ + Cl₂ → CH₃Cl + HCl (in sunlight)


3. **From Alkenes:**

- Addition of HX or X₂  

  CH₂=CH₂ + HBr → CH₃CH₂Br


4. **Finkelstein Reaction:**

R–Cl + NaI → R–I + NaCl (in acetone)


5. **Swarts Reaction:**

R–Cl + AgF → R–F + AgCl


────────────────────────

๐Ÿ”ธ PHYSICAL PROPERTIES


๐Ÿ“Œ Boiling Point:

- Increases with molar mass and number of halogens  

- For isomers: straight-chain > branched


๐Ÿ“Œ Solubility:

- Insoluble in water  

- Soluble in organic solvents


๐Ÿ“Œ Density Order:

Iodo > Bromo > Chloro > Fluoro compounds


────────────────────────

๐Ÿ”ธ CHEMICAL REACTIONS


๐Ÿ“Œ Nucleophilic Substitution:


1. **SN1 Mechanism** (Unimolecular):

- 2 steps:  

  Step 1: R–X → R⁺ + X⁻ (slow)  

  Step 2: R⁺ + Nu⁻ → R–Nu (fast)  

- Favoured by: 3° alkyl halide  

- Rate ∝ [R–X]  

- Racemization occurs


2. **SN2 Mechanism** (Bimolecular):

- 1 step (concerted):  

  R–X + Nu⁻ → R–Nu + X⁻  

- Favoured by: 1° alkyl halide  

- Rate ∝ [R–X][Nu⁻]  

- Inversion of configuration (Walden inversion)


๐Ÿ“Œ Elimination Reaction (dehydrohalogenation):

R–CH₂–CH₂–X + alc. KOH → R–CH=CH₂ + HX  

- Zaitsev's Rule: More substituted alkene is major product


๐Ÿ“Œ Reaction with Metals:

- **Wurtz Reaction:**  

  2R–X + 2Na → R–R + 2NaX (in dry ether)  

- **Grignard Reagent Formation:**  

  R–X + Mg → R–MgX (in dry ether)


────────────────────────

๐Ÿ”ธ HALOARENES (AROMATIC HALIDES)


๐Ÿ“Œ Reactivity:

- Less reactive than haloalkanes toward nucleophilic substitution  

- Due to resonance and partial double bond character in C–X bond


๐Ÿ“Œ Electrophilic Substitution:

- Halogen is **ortho/para directing**, deactivating group  

- Common reactions:  

  → Nitration: Ar–X + HNO₃/H₂SO₄ → NO₂–Ar–X  

  → Sulphonation: Ar–X + H₂SO₄ → SO₃H–Ar–X


๐Ÿ“Œ Nucleophilic Substitution in Haloarenes:

- Needs strong conditions  

- Mechanism: Elimination–Addition via **benzyne intermediate**


Example:

C₆H₅Cl + NaOH → C₆H₅OH (at 623K and 300 atm)


────────────────────────

๐Ÿ”ธ ENVIRONMENTAL EFFECTS


๐Ÿ“Œ Chloroform (CHCl₃):

- Anaesthetic, reacts with air to form phosgene (COCl₂) – toxic


๐Ÿ“Œ CFCs (e.g., Freon-12: CCl₂F₂):

- Used as refrigerants  

- Cause ozone layer depletion


────────────────────────

๐Ÿง  QUICK REVISION:


✔ SN1: 3° halides, polar solvents, racemization  

✔ SN2: 1° halides, strong nucleophile, inversion  

✔ Haloarenes: Show electrophilic substitution, not SN1/SN2  

✔ Aryl halides resist nucleophilic substitution  

✔ Wurtz reaction → alkanes  

✔ Grignard reagents → versatile in organic synthesis


๐Ÿ“Œ Order of reactivity:

R–I > R–Br > R–Cl > R–F  

Aryl halides < Alkyl halides (for substitution)


๐Ÿ”น CHAPTER 10: ALCOHOLS, PHENOLS AND ETHERS – Key Reactions, Formulas & Concepts


๐Ÿ“˜ INTRODUCTION:


๐Ÿ“Œ Alcohols: Compounds with –OH group attached to alkyl chain (R–OH)  

๐Ÿ“Œ Phenols: –OH group attached to aromatic ring (Ar–OH)  

๐Ÿ“Œ Ethers: Compounds with R–O–R′ structure (alkyl or aryl)


────────────────────────

๐Ÿ”ธ CLASSIFICATION


๐Ÿ“Œ Alcohols:

- 1° (Primary): –OH on 1° carbon (CH₃CH₂OH)  

- 2° (Secondary): CH₃–CHOH–CH₃  

- 3° (Tertiary): (CH₃)₃COH


๐Ÿ“Œ Phenols:

- Monohydric: C₆H₅OH  

- Dihydric: Catechol, Resorcinol  

- Trihydric: Pyrogallol


๐Ÿ“Œ Ethers:

- Symmetrical: CH₃–O–CH₃  

- Unsymmetrical: CH₃–O–C₂H₅


────────────────────────

๐Ÿ”ธ PREPARATION OF ALCOHOLS


1. **From Alkenes:**

- Hydration:

  \[

  CH₂=CH₂ + H₂O \xrightarrow{H⁺} CH₃CH₂OH

  \]


- Hydroboration–Oxidation:

  \[

  CH₂=CH₂ \xrightarrow{BH₃, H₂O₂/OH⁻} CH₃CH₂OH

  \]  

  → Anti-Markovnikov addition


2. **From Carbonyl Compounds:**

- Reduction:

  \[

  RCHO + H₂ → RCH₂OH  

  RCOR′ + H₂ → RCH(OH)R′

  \]


3. **From Grignard Reagents:**

- With aldehydes/ketones:

  \[

  R–MgX + R′CHO → R′CH(OH)R

  \]


────────────────────────

๐Ÿ”ธ PREPARATION OF PHENOLS


1. **From Benzene Sulphonic Acid:**

  \[

  C₆H₅SO₃H + NaOH → C₆H₅OH + Na₂SO₃

  \]


2. **From Diazonium Salts:**

  \[

  C₆H₅N₂⁺Cl⁻ + H₂O → C₆H₅OH + N₂ + HCl

  \]


────────────────────────

๐Ÿ”ธ PREPARATION OF ETHERS


1. **Williamson’s Synthesis:**

  \[

  R–X + R′–ONa → R–O–R′ + NaX

  \]  

  (Best for unsymmetrical ethers)


────────────────────────

๐Ÿ”ธ PHYSICAL PROPERTIES


๐Ÿ“Œ Boiling Point Order:

Alcohols > Phenols > Ethers  

→ Due to hydrogen bonding


๐Ÿ“Œ Solubility:

- Alcohols and phenols: soluble in water (small chains)  

- Ethers: less soluble, no H-bonding with themselves


────────────────────────

๐Ÿ”ธ CHEMICAL REACTIONS


๐Ÿ“Œ Reactions of Alcohols:


1. **With HX:**

  \[

  R–OH + HBr → R–Br + H₂O

  \]  

  Order of reactivity: 3° > 2° > 1°


2. **Dehydration (E1 mechanism):**

  \[

  CH₃CH₂OH \xrightarrow{conc. H₂SO₄, 443K} CH₂=CH₂ + H₂O

  \]


3. **Oxidation:**

  - 1° Alcohol → Aldehyde → Acid  

  - 2° Alcohol → Ketone  

  - 3° Alcohol → No oxidation


๐Ÿ“Œ Reactions of Phenols:


1. **Electrophilic Substitution:**

- Nitration:

  \[

  C₆H₅OH + HNO₃ → o- & p-nitrophenol

  \]


- Bromination:

  \[

  C₆H₅OH + Br₂ → 2,4,6-tribromophenol

  \]


2. **Reaction with NaOH:**

  \[

  C₆H₅OH + NaOH → C₆H₅O⁻Na⁺ + H₂O

  \]


3. **Reimer-Tiemann Reaction:**

  \[

  C₆H₅OH + CHCl₃ + NaOH → o-Hydroxybenzaldehyde

  \]


๐Ÿ“Œ Reactions of Ethers:


1. **With Strong Acids (HI, HBr):**

  \[

  R–O–R′ + HI → R–I + R′–OH

  \]  

  SN1 or SN2 depending on structure


2. **Electrophilic Substitution in Aromatic Ethers:**

- Anisole (C₆H₅OCH₃) → ortho/para substitution


────────────────────────

๐Ÿ”ธ TESTS TO DISTINGUISH:


✔ Lucas Test (HCl + ZnCl₂):  

  - 3° Alcohol → immediate turbidity  

  - 2° → slow  

  - 1° → no turbidity


✔ FeCl₃ Test:  

  - Phenol gives violet color


────────────────────────

๐Ÿง  QUICK RECAP:


✔ Alcohols: H-bonding, dehydration to alkene, oxidizable  

✔ Phenols: More acidic, undergo EAS, form salts  

✔ Ethers: Low BP, cleavage with acids  

✔ Williamson synthesis → best for unsymmetrical ethers  

✔ Phenol → antiseptic, acidic in nature


๐Ÿ“Œ Order of acidity:  

Phenol > Alcohol > Water > Alkyne > Alkene


๐Ÿ“Œ Order of reactivity (Lucas test):  

3° > 2° > 1°


๐Ÿ”น CHAPTER 11: ALDEHYDES, KETONES AND CARBOXYLIC ACIDS – Reactions, Formulas & Concepts


๐Ÿ“˜ INTRODUCTION:


๐Ÿ“Œ Aldehydes (–CHO):  

General formula: R–CHO  

e.g., Formaldehyde (HCHO), Acetaldehyde (CH₃CHO)


๐Ÿ“Œ Ketones (–CO–):  

General formula: R–CO–R′  

e.g., Acetone (CH₃COCH₃)


๐Ÿ“Œ Carboxylic Acids (–COOH):  

General formula: R–COOH  

e.g., Acetic acid (CH₃COOH), Benzoic acid (C₆H₅COOH)


────────────────────────

๐Ÿ”ธ PREPARATION METHODS


๐Ÿ“Œ Aldehydes and Ketones:


1. **Oxidation of Alcohols:**

- 1° alcohol → Aldehyde  

- 2° alcohol → Ketone  

  \[

  RCH₂OH \xrightarrow{[O]} RCHO  

  R₂CHOH \xrightarrow{[O]} R₂CO

  \]


2. **Ozonolysis of Alkenes:**

  \[

  RCH=CHR′ + O₃ → RCHO + R′CHO or R′CO

  \]


3. **Hydration of Alkynes:**

  \[

  RC≡CH + H₂O \xrightarrow{Hg²⁺, H⁺} R–CO–CH₃

  \]


๐Ÿ“Œ Carboxylic Acids:


1. **Oxidation of Aldehydes or Alcohols:**

  \[

  RCHO \xrightarrow{[O]} RCOOH  

  RCH₂OH \xrightarrow{[O]} RCOOH

  \]


2. **Hydrolysis of Nitriles:**

  \[

  R–CN + 2H₂O → R–COOH + NH₃

  \]


3. **From Grignard Reagents:**

  \[

  R–MgX + CO₂ → RCOOMgX → RCOOH (on hydrolysis)

  \]


────────────────────────

๐Ÿ”ธ PHYSICAL PROPERTIES


๐Ÿ“Œ Boiling Point Order:  

Carboxylic Acid > Aldehyde/Ketone > Alcohol > Hydrocarbon  

→ Due to H-bonding in acids


๐Ÿ“Œ Solubility:  

- Lower members are water-soluble  

- Solubility decreases with increase in chain length


────────────────────────

๐Ÿ”ธ CHEMICAL REACTIONS


๐Ÿ“Œ **NUCLEOPHILIC ADDITION REACTIONS** (Aldehyde & Ketone):


1. **Addition of HCN:**

  \[

  RCHO + HCN → RCH(OH)CN

  \]


2. **Addition of NaHSO₃:**

  \[

  RCHO + NaHSO₃ → RCH(OH)SO₃Na

  \]


3. **Addition of Grignard Reagent:**

  \[

  RCHO + RMgX → RCH(OH)R (alcohol)


4. **Reduction:**

- To Alcohols:

  \[

  RCHO + H₂ → RCH₂OH  

  R₂CO + H₂ → R₂CHOH

  \]


- To Hydrocarbons:

  \[

  RCHO \xrightarrow{Zn-Hg/HCl} RH (Clemmensen)  

  RCHO \xrightarrow{NH₂NH₂/KOH} RH (Wolff–Kishner)

  \]


๐Ÿ“Œ **OXIDATION:**

- Aldehyde → Acid  

- Ketone → No change with mild oxidizers


๐Ÿ“Œ **Haloform Reaction:**

- Methyl ketone + Halogen (X₂) + Base → Carboxylate + CHX₃ (Haloform)

  \[

  CH₃COCH₃ + 3Cl₂ + 4NaOH → CH₃COONa + CHCl₃ + 3NaCl + 3H₂O

  \]


๐Ÿ“Œ **Aldol Condensation:**

- 2 Aldehyde/Ketone molecules (with ฮฑ-H) condense in base:

  \[

  2CH₃CHO → CH₃CH(OH)CH₂CHO → CH₃CH=CHCHO (on heating)

  \]


๐Ÿ“Œ **Cannizzaro Reaction:**

- Aldehydes without ฮฑ-H undergo disproportionation:

  \[

  2HCHO + NaOH → HCOONa + CH₃OH

  \]


๐Ÿ“Œ **Cross Aldol & Mixed Reactions:**

- Two different carbonyl compounds used


────────────────────────

๐Ÿ”ธ REACTIONS OF CARBOXYLIC ACIDS


1. **Acid–Base Reaction:**

  \[

  RCOOH + NaOH → RCOONa + H₂O

  \]


2. **Reduction:**

  \[

  RCOOH \xrightarrow{LiAlH₄} RCH₂OH

  \]


3. **Decarboxylation:**

  \[

  RCOONa + NaOH → RH + Na₂CO₃

  \]  

  (soda lime)


4. **Esterification:**

  \[

  RCOOH + R′OH \xrightarrow{H⁺} RCOOR′ + H₂O

  \]


5. **Substitution in Benzene Ring (Aromatic acids):**

- Ortho/Para directing group  

- e.g., nitration, sulphonation


────────────────────────

๐Ÿ”ธ TESTS TO IDENTIFY:


✔ Fehling’s Test:  

- Aldehydes → red ppt  

- Ketones → No reaction


✔ Tollen’s Test (Silver mirror):  

- Aldehydes → silver mirror  

- Ketones → No reaction


✔ Sodium bicarbonate test:  

- Carboxylic acids → brisk effervescence of CO₂


────────────────────────

๐Ÿง  QUICK RECAP:


✔ Aldehydes = More reactive than ketones  

✔ Nucleophilic addition = key for carbonyl compounds  

✔ Acidic strength: Formic acid > Acetic acid > Propanoic acid  

✔ Aldol reaction needs ฮฑ-H  

✔ Cannizzaro = no ฮฑ-H  

✔ Tollen's & Fehling's = tests for aldehydes  

✔ Esters = formed by acid + alcohol (sweet smell)


๐Ÿ“Œ Order of reactivity (Carbonyls):  

Formaldehyde > Aldehyde > Ketone


๐Ÿ”น CHAPTER 12: AMINES – Structure, Classification, Reactions & Properties


๐Ÿ“˜ INTRODUCTION:


๐Ÿ“Œ Amines are derivatives of ammonia (NH₃) where one or more hydrogen atoms are replaced by alkyl or aryl groups.


๐Ÿ“Œ General formula: R–NH₂, R₂NH, R₃N


────────────────────────

๐Ÿ”ธ CLASSIFICATION OF AMINES


๐Ÿ“Œ Based on number of alkyl/aryl groups attached to N:


- **Primary (1°) amine**: R–NH₂ (e.g., CH₃NH₂)  

- **Secondary (2°) amine**: R₂NH (e.g., CH₃–NH–CH₃)  

- **Tertiary (3°) amine**: R₃N (e.g., (CH₃)₃N)


๐Ÿ“Œ Based on nature of R group:

- **Aliphatic amines**: Alkyl group  

- **Aromatic amines**: Aryl group (e.g., Aniline: C₆H₅NH₂)


────────────────────────

๐Ÿ”ธ PREPARATION METHODS


๐Ÿ“Œ 1. **Reduction of Nitro Compounds:**

\[

R–NO₂ \xrightarrow{Sn/HCl \text{ or } H₂/Ni} R–NH₂

\]


๐Ÿ“Œ 2. **From Amides (Hofmann degradation):**

\[

R–CONH₂ + Br₂ + 4NaOH → R–NH₂ + Na₂CO₃ + 2NaBr + 2H₂O

\]


๐Ÿ“Œ 3. **From Halides (Gabriel Phthalimide Synthesis):**

\[

C₆H₄(CO)₂N–K + R–X → C₆H₄(CO)₂NR → R–NH₂ (on hydrolysis)

\]  

→ Only for **primary amines**


๐Ÿ“Œ 4. **From Cyanides:**

\[

R–CN \xrightarrow{H₂/Ni} R–CH₂–NH₂

\]


๐Ÿ“Œ 5. **Reductive Amination:**

\[

R–CHO + NH₃ + H₂ → R–CH₂–NH₂

\]


────────────────────────

๐Ÿ”ธ PHYSICAL PROPERTIES


๐Ÿ“Œ Boiling Point:

- 1° > 2° > 3°  

- H-bonding present in 1° and 2° amines


๐Ÿ“Œ Solubility:

- Lower amines are soluble in water due to H-bonding  

- Solubility decreases with increase in alkyl chain


๐Ÿ“Œ Basic Strength:

Amines are basic due to lone pair on N  

- Order (in aqueous): 2° > 1° > 3° > NH₃


────────────────────────

๐Ÿ”ธ CHEMICAL REACTIONS


๐Ÿ“Œ 1. **Reaction with HCl (Acid–Base):**

\[

R–NH₂ + HCl → R–NH₃⁺Cl⁻

\]


๐Ÿ“Œ 2. **Acylation (with acid chloride):**

\[

R–NH₂ + R′COCl → R′CONHR + HCl

\]  

(Only for 1° and 2° amines)


๐Ÿ“Œ 3. **Alkylation:**

\[

R–NH₂ + R′–X → R–NHR′ → R–NR′₂ (on excess alkyl halide)

\]


๐Ÿ“Œ 4. **Carbylamine Reaction:** (test for 1° amines)

\[

R–NH₂ + CHCl₃ + alc. KOH → R–NC + 3KCl + 3H₂O  

\]  

→ Foul smell of isocyanide


๐Ÿ“Œ 5. **Reaction with Nitrous Acid:**

- 1° aliphatic amine:

  \[

  R–NH₂ + HNO₂ → R–OH + N₂ + H₂O

  \]


- 1° aromatic amine (Aniline):

  \[

  C₆H₅NH₂ + HNO₂ → C₆H₅–N₂⁺Cl⁻ + 2H₂O  

  \]  

  (Diazonium salt at 273K)


๐Ÿ“Œ 6. **Hinsberg Test (Distinguish 1°, 2°, 3° Amines):**


- Reagent: Benzenesulphonyl chloride (PhSO₂Cl)


| Type | Reaction with PhSO₂Cl | Behavior |

|-----------|----------------------------|---------------------|

| 1° Amine | Forms soluble sulphonamide | Dissolves in base |

| 2° Amine | Forms insoluble sulphonamide | Does not dissolve |

| 3° Amine | No reaction | No change |


────────────────────────

๐Ÿ”ธ DIAZONIUM SALTS (Important Part)


๐Ÿ“Œ Benzene diazonium chloride:

\[

C₆H₅–N₂⁺Cl⁻  

\]  

Formed by reaction of aniline with HNO₂ at 0–5°C


๐Ÿ“Œ Sandmeyer Reaction:

\[

C₆H₅–N₂⁺Cl⁻ + CuCl/HCl → C₆H₅Cl  

C₆H₅–N₂⁺Cl⁻ + CuBr/HBr → C₆H₅Br

\]


๐Ÿ“Œ Gattermann Reaction:

\[

C₆H₅–N₂⁺Cl⁻ + Cu/HCl → C₆H₅Cl


๐Ÿ“Œ Replacement Reactions:

- CN: C₆H₅CN  

- OH: C₆H₅OH  

- I: C₆H₅I (with KI)  

- H: C₆H₆ (with hypophosphorous acid)


๐Ÿ“Œ Coupling Reaction:

\[

C₆H₅–N₂⁺Cl⁻ + Ar–OH → Azo dye (Ar–N=N–Ph)

\]


────────────────────────

๐Ÿง  QUICK RECAP:


✔ Amines: Basic in nature, lone pair on N  

✔ Primary amines → carbylamine test + diazonium salt  

✔ Diazotisation temp = 273–278K  

✔ Hinsberg → distinguish 1°, 2°, 3°  

✔ Gabriel synthesis: Only 1° amines  

✔ Sandmeyer & Gattermann = substitution via diazonium salt  

✔ Aromatic amines less basic due to resonance


๐Ÿ”น CHAPTER 13: BIOMOLECULES – Structure, Types, and Functions


๐Ÿ“˜ INTRODUCTION:


Biomolecules are organic molecules found in living organisms that play structural and functional roles in life processes.


๐Ÿ”ธ Major Classes:

✔ Carbohydrates  

✔ Proteins  

✔ Enzymes  

✔ Vitamins  

✔ Nucleic acids


────────────────────────

๐Ÿ”ธ CARBOHYDRATES


๐Ÿ“Œ General Formula: Cโ‚“(H₂O)แตง  

→ Polyhydroxy aldehydes or ketones


๐Ÿ“Œ Classification:


1. **Monosaccharides** – Single sugar unit  

  e.g., Glucose (C₆H₁₂O₆), Fructose


2. **Disaccharides** – Two monosaccharides  

  e.g., Sucrose = Glucose + Fructose  

        Lactose = Glucose + Galactose


3. **Polysaccharides** – Many sugar units  

  e.g., Starch, Cellulose, Glycogen


๐Ÿ“Œ Reducing Sugars:

- Reduce Tollen’s/Fehling’s reagent  

- All monosaccharides + lactose, maltose  

- Sucrose is **non-reducing**


๐Ÿ“Œ Glucose Structure:

- Open-chain: Aldehyde group at one end  

- Cyclic (Haworth): Pyranose ring (6-membered)


๐Ÿ“Œ Mutarotation:

- Change in optical rotation due to interconversion of ฮฑ and ฮฒ forms


────────────────────────

๐Ÿ”ธ PROTEINS


๐Ÿ“Œ Polymers of ฮฑ-amino acids  

General structure of amino acid:  

\[

\text{H}_2\text{N}–CH(R)–COOH

\]


๐Ÿ“Œ Zwitterion:  

At isoelectric point, amino acid exists as dipolar ion:

\[

^+NH₃–CH(R)–COO⁻

\]


๐Ÿ“Œ Classification:


1. **Fibrous Proteins**: Structural, insoluble (e.g., keratin)  

2. **Globular Proteins**: Functional, soluble (e.g., enzymes, hormones)


๐Ÿ“Œ Structure Levels:


- **Primary**: Sequence of amino acids  

- **Secondary**: ฮฑ-helix or ฮฒ-sheet (H-bonding)  

- **Tertiary**: 3D folding  

- **Quaternary**: Multiple polypeptides


๐Ÿ“Œ Denaturation:

Loss of 3D structure due to heat/pH → protein loses function


────────────────────────

๐Ÿ”ธ ENZYMES


๐Ÿ“Œ Enzymes = Biological catalysts  

- Highly specific  

- Work at body temperature and pH


๐Ÿ“Œ Mechanism:  

Enzyme + Substrate → Enzyme–Substrate Complex → Product + Enzyme


๐Ÿ“Œ Examples:

- Amylase (starch digestion)  

- Pepsin (protein digestion in stomach)


────────────────────────

๐Ÿ”ธ VITAMINS


๐Ÿ“Œ Organic compounds required in small amounts


๐Ÿ“Œ Classification:


1. **Water-Soluble**: B-complex, C  

  – Not stored, need regular intake


2. **Fat-Soluble**: A, D, E, K  

  – Stored in body fat


๐Ÿ“Œ Deficiency Diseases:


| Vitamin | Deficiency Disease |

|---------|----------------------------|

| A | Night blindness |

| B₁ | Beriberi |

| C | Scurvy |

| D | Rickets |

| K | Blood clotting disorder |


────────────────────────

๐Ÿ”ธ NUCLEIC ACIDS


๐Ÿ“Œ Genetic material made of nucleotides  

→ Nucleotide = Base + Sugar + Phosphate


๐Ÿ“Œ Types:


1. **DNA** (Deoxyribonucleic acid)  

  - Sugar: Deoxyribose  

  - Bases: A, T, G, C  

  - Double-stranded helix (Watson–Crick model)


2. **RNA** (Ribonucleic acid)  

  - Sugar: Ribose  

  - Bases: A, U, G, C  

  - Single-stranded


๐Ÿ“Œ Base Pairing in DNA:

A–T (2 H-bonds), G–C (3 H-bonds)


๐Ÿ“Œ Functions:


- DNA: Genetic code for heredity  

- RNA: Protein synthesis (mRNA, tRNA, rRNA)


────────────────────────

๐Ÿง  QUICK RECAP:


✔ Carbohydrates = Energy source  

✔ Glucose = Aldohexose; Fructose = Ketohexose  

✔ Sucrose = Non-reducing sugar  

✔ Proteins = Made of amino acids  

✔ Enzymes = Biological catalysts  

✔ Vitamins = Micronutrients (fat/water soluble)  

✔ DNA = Genetic code; RNA = Protein synthesis  

✔ Mutarotation & Zwitterion = key concepts  

✔ Denaturation = Protein loses function  

✔ Tollen’s & Fehling’s test = For reducing sugars


๐Ÿ“Œ Important Reaction (Glucose with HCN):

\[C₆H₁₂O₆ + HCN → C₆H₁₂O₆CN (cyanohydrin)\]


๐Ÿ”น CHAPTER 14: POLYMERS – Types, Mechanisms & Examples


๐Ÿ“˜ INTRODUCTION:


๐Ÿ“Œ Polymer: High molecular weight macromolecule formed by the repetition of small units (monomers).  

๐Ÿ“Œ Polymerization: Process of forming polymers from monomers.


────────────────────────

๐Ÿ”ธ TYPES OF POLYMERS


๐Ÿ“Œ Based on Source:


1. **Natural Polymers** – Found in nature  

   e.g., Proteins, Starch, Rubber, Cellulose


2. **Synthetic Polymers** – Man-made  

   e.g., Nylon-6,6, PVC, Teflon


3. **Semi-synthetic** – Chemically modified natural polymers  

   e.g., Rayon (from cellulose)


๐Ÿ“Œ Based on Polymerization:


1. **Addition Polymers**  

   – Made from unsaturated monomers (double/triple bond)  

   – No by-product  

   – e.g., Polyethene, Teflon, PVC


2. **Condensation Polymers**  

   – Monomers combine with elimination of small molecules (like H₂O, HCl)  

   – e.g., Nylon, Bakelite, Terylene


๐Ÿ“Œ Based on Structure:


1. **Linear Polymers** – e.g., High-density polyethene (HDPE)  

2. **Branched Chain** – e.g., Low-density polyethene (LDPE)  

3. **Cross-linked** – e.g., Bakelite


๐Ÿ“Œ Based on Molecular Forces:


| Type | Properties | Example |

|-------------------|------------------------------|------------------|

| Elastomers | Elastic, weak bonds | Natural rubber |

| Fibres | High tensile strength | Nylon, Terylene |

| Thermoplastics | Soften on heating | PVC, Polythene |

| Thermosetting | Hard, infusible on heating | Bakelite, Melamine |


────────────────────────

๐Ÿ”ธ ADDITION POLYMERS


๐Ÿ“Œ 1. **Polyethene**  

- Monomer: Ethene (CH₂=CH₂)  

- Types:

  – LDPE: Branched, soft  

  – HDPE: Linear, hard


๐Ÿ“Œ 2. **Polystyrene**  

- Monomer: Styrene (C₆H₅–CH=CH₂)  

- Uses: Toys, packaging


๐Ÿ“Œ 3. **PVC (Polyvinyl chloride)**  

- Monomer: Vinyl chloride (CH₂=CHCl)  

- Uses: Pipes, synthetic leather


๐Ÿ“Œ 4. **Teflon (PTFE)**  

- Monomer: CF₂=CF₂  

- Uses: Non-stick cookware, insulation


๐Ÿ“Œ 5. **Acrylonitrile Polymer (PAN):**  

- Monomer: CH₂=CH–CN  

- Uses: Synthetic wool


────────────────────────

๐Ÿ”ธ CONDENSATION POLYMERS


๐Ÿ“Œ 1. **Nylon-6,6**  

- Monomers: Hexamethylenediamine + Adipic acid  

- Reaction:  

  \[

  HOOC–(CH₂)₄–COOH + H₂N–(CH₂)₆–NH₂ → Nylon-6,6 + H₂O

  \]  

- Uses: Fibres, ropes, textiles


๐Ÿ“Œ 2. **Terylene (Dacron)**  

- Monomers: Ethylene glycol + Terephthalic acid  

- Uses: Fabric, PET bottles


๐Ÿ“Œ 3. **Bakelite**  

- Monomers: Phenol + Formaldehyde  

- Cross-linked polymer  

- Uses: Electrical insulators, handles


๐Ÿ“Œ 4. **Melamine-formaldehyde resin**  

- Heat-resistant plastic used in kitchenware


────────────────────────

๐Ÿ”ธ NATURAL POLYMERS


| Polymer | Monomer | Use |

|-------------|--------------------|------------------|

| Starch | Glucose | Energy storage |

| Cellulose | Glucose | Plant cell walls |

| Protein | Amino acids | Body structure |

| Natural rubber | Isoprene (2-methyl-1,3-butadiene) | Elastic materials |


────────────────────────

๐Ÿ”ธ VULCANISATION OF RUBBER


๐Ÿ“Œ Natural rubber is soft and sticky.  

๐Ÿ“Œ Vulcanisation: Heating rubber with sulfur  

→ Increases strength, elasticity, heat resistance


๐Ÿ“Œ Monomer of rubber:

\[

CH₂=C(CH₃)–CH=CH₂ \quad \text{(Isoprene)}

\]


────────────────────────

๐Ÿ”ธ BIODEGRADABLE & NON-BIODEGRADABLE POLYMERS


๐Ÿ“Œ Biodegradable Polymers:

- Can be broken down by microbes  

- e.g., PHBV (Poly ฮฒ-hydroxybutyrate-co-ฮฒ-hydroxyvalerate)  

  – Monomers: 3-hydroxybutanoic acid + 3-hydroxypentanoic acid


๐Ÿ“Œ Non-biodegradable: PVC, Polystyrene, Nylon


────────────────────────

๐Ÿง  QUICK RECAP:


✔ Addition Polymers = No by-products  

✔ Condensation Polymers = Elimination of H₂O/HCl  

✔ PVC = CH₂=CHCl → Pipes  

✔ Teflon = CF₂=CF₂ → Non-stick  

✔ Nylon-6,6 → Condensation of diamine + dicarboxylic acid  

✔ Bakelite = Thermosetting  

✔ LDPE vs HDPE = branching  

✔ Biodegradable = PHBV, polylactic acid  

✔ Natural rubber = soft; Vulcanised = strong


๐Ÿ“Œ Polyblend: Mixture of 2 or more polymers for better quality


๐Ÿ“Œ Copolymers: Made from 2 different monomers (e.g., Buna-S)



๐Ÿ”น CHAPTER 15: CHEMISTRY IN EVERYDAY LIFE – Drugs, Detergents & Additives


๐Ÿ“˜ INTRODUCTION:


Chemistry plays a vital role in our daily life through medicines, food additives, soaps, detergents, and artificial sweeteners.


────────────────────────

๐Ÿ”ธ DRUGS & THEIR CLASSIFICATION


๐Ÿ“Œ **Drug**: A chemical substance used to diagnose, prevent or treat diseases.


๐Ÿ“Œ Classification Based On:


1. **Pharmacological effect**  

   → e.g., Analgesics, Antipyretics


2. **Drug action** (target system)  

   → e.g., Inhibits enzyme, receptor blocker


3. **Chemical structure**  

   → e.g., Sulpha drugs, Penicillin


4. **Molecular targets**  

   → Enzymes or receptors involved in the process


────────────────────────

๐Ÿ”ธ TYPES OF DRUGS


๐Ÿ“Œ **1. Antacids**  

→ Neutralize excess acid in the stomach  

- e.g., Aluminium hydroxide, Magnesium hydroxide  

- Modern antacids: Omeprazole, Ranitidine


๐Ÿ“Œ **2. Antihistamines**  

→ Treat allergy by blocking histamine receptors  

- e.g., Diphenhydramine, Cimetidine


๐Ÿ“Œ **3. Neurologically Active Drugs**


- **Analgesics** (Pain relievers):  

  - Non-narcotic: Aspirin, Paracetamol  

  - Narcotic: Morphine, Codeine


- **Tranquilizers** (Mental disorders):  

  - e.g., Diazepam, Alprazolam, Equanil


๐Ÿ“Œ **4. Antimicrobials**  

→ Kill or inhibit microorganisms  

Types:

- Antibiotics: Penicillin, Ampicillin  

- Antiseptics: Dettol, Iodine  

- Disinfectants: Phenol, Chlorine (used on non-living surfaces)


๐Ÿ“Œ **5. Antifertility Drugs**  

→ Prevent conception  

- e.g., Mifepristone, Norethindrone


────────────────────────

๐Ÿ”ธ CHEMICALS IN FOOD


๐Ÿ“Œ **1. Artificial Sweeteners**

- Provide sweetness without calories  

- Examples:

  - Saccharin  

  - Aspartame (unstable at high temp)  

  - Sucralose (stable)


๐Ÿ“Œ **2. Food Preservatives**

- Prevent spoilage from microbes  

- Examples: Sodium benzoate, Salt, Sugar, Vinegar


๐Ÿ“Œ **3. Antioxidants**

- Prevent oxidation of food  

- e.g., BHA (Butylated hydroxyanisole), BHT


────────────────────────

๐Ÿ”ธ CLEANSING AGENTS


๐Ÿ“Œ **1. Soaps**

- Sodium or potassium salts of long-chain fatty acids  

- Made by **saponification**:

  \[

  Fat + NaOH → Glycerol + Soap

  \]


- Not effective in hard water (forms scum with Ca²⁺, Mg²⁺)


๐Ÿ“Œ **2. Synthetic Detergents**

- Made from petrochemicals  

- Work in hard and soft water  

Types:

- Anionic: Sodium lauryl sulphate (toothpaste, shampoo)  

- Cationic: Cetyltrimethylammonium bromide (hair conditioner)  

- Non-ionic: No charge; mild, used in liquids


────────────────────────

๐Ÿ”ธ ENVIRONMENT & HEALTH


๐Ÿ“Œ **Antibiotics misuse** → Resistance  

๐Ÿ“Œ **Detergents** → Non-biodegradable → Pollution  

๐Ÿ“Œ **Preservatives and colors** → Toxic in high doses  

๐Ÿ“Œ Safe use of chemicals is essential for health


────────────────────────

๐Ÿง  QUICK RECAP:


✔ Antacids = Neutralize HCl in stomach  

✔ Antihistamines = Block allergy receptors  

✔ Analgesics = Painkillers (narcotic/non-narcotic)  

✔ Tranquilizers = Treat anxiety and mental disorders  

✔ Antibiotics = Kill/inhibit bacteria  

✔ Antiseptics = Used on body  

✔ Disinfectants = Used on floors/surfaces  

✔ Sweeteners: Saccharin (heat stable), Aspartame (not heat stable)  

✔ Soaps = Not for hard water  

✔ Detergents = Work in all types of water  

✔ Preservatives = Prevent microbial growth in food


๐Ÿ“Œ Saponification: Fat + Base → Soap + Glycerol  

๐Ÿ“Œ Drug-Target Interaction: Receptor or enzyme inhibition


๐Ÿ”š **Conclusion: Your Success in Chemistry Starts Here**


With this complete chapter-wise collection of **Class 12 Chemistry formulas**, you now have the most powerful and exam-ready tool at your fingertips. Whether you're preparing for **board exams (CBSE/AHSEC)** or competitive tests like **NEET, JEE, CUET**, mastering formulas is the **foundation to scoring high and solving questions quickly**.


At **Vidya Unnati Academy**, we believe in learning smart, not hard. These formulas are not just for memorization — they’re for application. Use them while practicing questions, solving previous years’ papers, or revising before exams.


๐Ÿง  **Our Final Advice:**

1. ๐Ÿ“– **Revise regularly** – even 15 minutes a day can build long-term retention.  

2. ๐Ÿงช **Apply the formulas in MCQs and numerical questions** — don’t just read them.  

3. ๐Ÿ“ **Create your own short notes** alongside this list for maximum clarity.  

4. ๐Ÿ’ฌ **Join study groups or coaching discussions** to test your understanding.  

5. ๐Ÿง˜ **Take care of your health, sleep, and peace of mind** — they matter as much as formulas.


๐ŸŽฏ Keep visiting **Vidya Unnati Academy** for more such full syllabus content, PDF downloads, practice tests, and exclusive exam strategies designed just for students like you.


๐Ÿ“Œ **If this post helped you, don’t forget to bookmark, share, and comment your feedback. Your support motivates us to keep creating free resources for students across India.**


✨ **All the best for your Chemistry journey — You’ve got this!**


– Team **Vidya Unnati Academy**

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