NEET Chemistry Formula Sheet | Complete Chapter-wise Formulas

⚡ Physical Chemistry Class 11 & 12

Some Basic Concepts

Mole Concept

n = m/M

n = number of moles, m = mass, M = molar mass

Number of Particles

N = n × N_A

N_A = 6.022 × 10²³ mol⁻¹

Molarity (M)

M = moles of solute / Volume (L)

Concentration in mol/L

Molality (m)

m = moles of solute / mass of solvent (kg)

Temperature independent

Mole Fraction (X)

X_A = n_A / (n_A + n_B)

Sum of all mole fractions = 1

% Composition

% = (mass of component / total mass) × 100

Thermodynamics

First Law

ΔU = q + W

Change in internal energy

Enthalpy

ΔH = ΔU + PΔV

Heat at constant pressure

Entropy

ΔS = q_rev / T

Measure of disorder

Gibbs Free Energy

ΔG = ΔH − TΔS

Spontaneity: ΔG < 0

Helmholtz Energy

ΔA = ΔU − TΔS

At constant volume

Heat Capacity

q = C × ΔT

C = heat capacity

Equilibrium

Equilibrium Constant (K_c)

K_c = [C]^c[D]^d / [A]^a[B]^b

For aA + bB ⇌ cC + dD

K_p and K_c

K_p = K_c(RT)^Δn

Δn = (c+d) − (a+b)

Acid Dissociation (K_a)

K_a = [H⁺][A⁻] / [HA]

Weak acid equilibrium

Base Dissociation (K_b)

K_b = [B⁺][OH⁻] / [BOH]

Weak base equilibrium

pH

pH = −log[H⁺]

pOH = −log[OH⁻], pH + pOH = 14

Henderson-Hasselbalch

pH = pK_a + log([A⁻]/[HA])

For buffer solutions

Solubility Product (K_sp)

K_sp = [A⁺]^a[B⁻]^b

For salt A_aB_b

Electrochemistry

Nernst Equation

E = E° − (RT/nF) ln Q

At 25°C: E = E° − (0.0591/n) log Q

Gibbs Free Energy (Cell)

ΔG° = −nFE°

F = 96500 C/mol

Faraday's First Law

w = ZIt

w = mass deposited, Z = electrochemical equivalent

Conductivity

κ = G × l/A

G = conductance, l/A = cell constant

Molar Conductivity

Λ_m = κ × 1000 / M

M = molarity

Chemical Kinetics

Rate Law

Rate = k[A]^x[B]^y

x, y = order of reaction

Zero Order

[A] = [A]₀ − kt

t_1/2 = [A]₀/2k

First Order

ln[A] = ln[A]₀ − kt

t_1/2 = 0.693/k

Second Order

1/[A] = 1/[A]₀ + kt

t_1/2 = 1/k[A]₀

Arrhenius Equation

k = A·e^−Ea/RT

ln k = ln A − Ea/RT

Half-life (1st Order)

t_1/2 = 0.693/k

Independent of initial concentration

🧪 Organic Chemistry Class 11 & 12

General Organic Chemistry

Degree of Unsaturation

DU = (2C + 2 + N − H − X) / 2

C = carbons, H = hydrogens, X = halogens, N = nitrogens

Hybridization

sp³ (tetrahedral), sp² (trigonal planar), sp (linear)

Inductive Effect

-I (electron withdrawing), +I (electron donating)

Resonance

Delocalization of π electrons

Stabilizes molecule

Important Named Reactions

Aldol Condensation

2 RCHO → RCH(OH)CHRCHO

Aldehyde/Ketone + dilute base

Cannizzaro Reaction

2 RCHO → RCH₂OH + RCOOK

Aldehyde + conc. KOH (no α-H)

Friedel-Crafts Alkylation

ArH + RCl → ArR + HCl

Anhydrous AlCl₃ catalyst

Friedel-Crafts Acylation

ArH + RCOCl → ArCOR + HCl

Grignard Reagent

RMgX + H₂O → RH + Mg(OH)X

Alkyl/aryl magnesium halide

Wurtz Reaction

2R-X + 2Na → R-R + 2NaX

Alkane formation

Sandmeyer Reaction

ArN₂⁺X⁻ + CuCl/HCl → ArCl + N₂

Diazotization

ArNH₂ + NaNO₂/HCl → ArN₂⁺Cl⁻

Functional Groups

Alcohols

R-OH

Primary, secondary, tertiary

Aldehydes

R-CHO

-CHO group

Ketones

R-CO-R'

C=O with two alkyl groups

Carboxylic Acids

R-COOH

-COOH group

Amines

R-NH₂

Primary, secondary, tertiary

Ethers

R-O-R'

Esters

R-COOR'

Amides

R-CONH₂

⚗️ Inorganic Chemistry Class 11 & 12

Periodic Table

Ionization Energy

IE₁ < IE₂ < IE₃

Increases across period, decreases down group

Electronegativity

F (4.0) > O > Cl > N > Br > I > S > C > H

Pauling scale

Atomic Radius

Decreases across period, increases down group

Electron Affinity

Most negative: Cl > F > Br > I

Chemical Bonding

Bond Order

BO = (N_b − N_a) / 2

N_b = bonding electrons, N_a = antibonding electrons

VSEPR Theory

Electron pairs repel, determine shape

Dipole Moment

μ = q × d

q = charge, d = bond length

% Ionic Character

%IC = (observed μ / calculated μ) × 100

Coordination Compounds

Effective Atomic Number

EAN = Z − (oxidation state) + 2 × (CN)

Z = atomic number, CN = coordination number

Crystal Field Splitting

Δ_o for octahedral, Δ_t for tetrahedral

CFSE (Octahedral)

CFSE = (−0.4x + 0.6y)Δ_o

x = electrons in t₂g, y = electrons in e_g

🔢 Key Constants for NEET Chemistry

Avogadro's Number

N_A = 6.022 × 10²³ mol⁻¹

Gas Constant

R = 8.314 J·mol⁻¹·K⁻¹ = 0.0821 L·atm·mol⁻¹·K⁻¹

Faraday's Constant

F = 96500 C/mol

Planck's Constant

h = 6.626 × 10⁻³⁴ J·s

Speed of Light

c = 3 × 10⁸ m/s

1 Faraday

1 F = 96500 C = 1 mole of electrons