25 Days to Go for JEE Advanced 2024 Exam; Important Chemistry Formulas to Learn by Heart

Ideal Gas Law

PV = nRT

Kinetic Energy of Gas Molecules

KE = (3/2)RT

T(K) = T^∘C + 273.15

Molarity

(M) = Number of Moles of Solutes/Volume of Solution in Liters

Unit: mole/L

Molality

(m) = Number of Moles of Solutes/Mass of solvent in kg

Molecular Mass

2 × vapour density

Atomic number

Number of protons in the nucleus = Number of electrons in the nucleus

Mass number

Number of protons + Number of neutrons C =vλ

Boyle’s Law

P₁V₁ = P₂V₂ (at constant T and n)

Charles’s Law

V₁/T₁ = V₂/T₂ (at constant P and n)

Avogadro's Law

V/n = constant, where V is the volume and n is the number of moles.

Dalton's Law of Partial Pressures

P(total) = P₁+P₂+P₃+….., where P(total) is the total pressure and P₁, P₂, P₃ etc. are the partial pressures of individual gases in the mixture.

Enthalpy

H = U+pV

First Law of Thermodynamics

ΔU = q+W

Ohm’s Law

V = RI

Faraday’s Laws

• Faraday’s First Law of Electrolysis: M = Zit, Z = Atomic Mass / n × F

• Faraday’s Second Law of Electrolysis: M1/M2 = E1/E2

Freundlich Adsorption Isotherm

[x/m] − Kp^(1/n); n≥1

Henry's Law

S = kH×P

Where S is the solubility of a gas in a liquid, P is the partial pressure of the gas above the liquid, and kH is Henry's law constant.

Nernst Equation

E = E^∘− (RT/nF) lnQ

Where E is the cell potential, E∘ is the standard cell potential, R is the gas constant, T is the temperature, n is the number of electrons transferred, F is the Faraday constant, and Q is the reaction quotient.

Henderson-Hasselbalch Equation

pH = pKa+log([A⁻]/[HA])

Where pH is the negative logarithm of the hydrogen ion concentration, pKa is the acid dissociation constant, [A⁻] is the concentration of the conjugate base, and [HA] is the concentration of the acid.

Beer-Lambert Law

A = ϵbc

Where A is the absorbance, ϵ is the molar absorptivity, b is the path length, and c is the concentration.