Chemistry Formula Sheet
62+ JEE/NEET/CBSE formulas across 14 chapters with KaTeX-rendered equations and variable definitions. Free, no login needed.
Showing 62 of 62 formulas
Chapter 1: Some Basic Concepts of Chemistry
Mole conceptJEENEETCBSE
where: n = moles, m = mass (g), M = molar mass (g/mol), N = number of particles, N_A = 6.022\times 10^{23}
MolarityJEENEETCBSE
where: Concentration in mol/L. Temperature-dependent (volume changes).
MolalityJEENEETCBSE
where: Concentration in mol/kg. Temperature-independent.
Mole fractionJEENEETCBSE
where: Dimensionless ratio of moles of A to total moles.
Percentage compositionCBSENEET
where: Mass-based elemental composition of a compound.
Empirical → molecular formulaJEECBSE
where: Molecular formula = (empirical formula)_n.
Chapter 2: Structure of Atom
Bohr radius (n-th orbit)JEENEET
where: n = principal quantum number, Z = atomic number.
Bohr energy (n-th orbit, H-like)JEENEET
where: Energy of the n-th orbit. Negative ⇒ bound state.
Rydberg formulaJEENEET
where: R_H = 1.097\times 10^{7}\,\text{m}^{-1}; n_2 > n_1.
de Broglie wavelengthJEENEET
where: h = 6.626\times 10^{-34}\,\text{J·s}.
Heisenberg uncertaintyJEE
where: Position–momentum uncertainty product floor.
Photon energyJEENEETCBSE
where: c = 3\times 10^{8}\,\text{m/s}.
Chapter 5: States of Matter (Gases & Liquids)
Ideal gas equationJEENEETCBSE
where: R = 0.0821\,\text{L·atm·K}^{-1}\!\text{·mol}^{-1} = 8.314\,\text{J·K}^{-1}\!\text{·mol}^{-1}.
Boyle's LawCBSENEET
where: Isothermal process.
Charles's LawCBSENEET
where: Isobaric process. T in Kelvin.
Dalton's Law of Partial PressuresJEENEETCBSE
where: Mixture of non-reacting gases.
Graham's Law of DiffusionJEENEET
where: Rate of effusion ∝ 1/√M at same T, P.
RMS speedJEENEET
where: Average kinetic-molecular speed; M in kg/mol.
van der Waals equationJEE
where: Real-gas correction; a (attraction), b (excluded volume).
Chapter 6: Thermodynamics
First Law of ThermodynamicsJEENEETCBSE
where: Sign convention: w = work done ON the system; q = heat absorbed BY system.
Enthalpy definitionJEENEETCBSE
where: \Delta n_g = (n_{\text{gas, products}} - n_{\text{gas, reactants}}).
Hess's LawJEENEETCBSE
where: Path-independence of state functions.
Gibbs free energyJEENEETCBSE
where: \Delta G < 0 ⇒ spontaneous at constant T, P.
Gibbs–Helmholtz (equilibrium)JEENEET
where: K = thermodynamic equilibrium constant.
Work — isothermal reversible expansionJEENEET
where: Ideal gas; reversible isothermal.
Entropy of mixing / phase changeJEENEET
where: For phase change: \Delta S = \Delta H_{\text{fus/vap}}/T.
Chapter 7: Equilibrium
K_c – K_p relationJEENEETCBSE
where: \Delta n_g = moles gaseous products – moles gaseous reactants.
Reaction quotientJEENEET
where: Q < K → forward; Q = K → equilibrium; Q > K → reverse.
Ostwald's dilution law (weak electrolyte)JEENEET
where: α = degree of dissociation, c = concentration.
pH and water autoionizationJEENEETCBSE
where: pH + pOH = 14 at 25 °C.
Henderson–HasselbalchJEENEETCBSE
where: Buffer solution pH; valid when α small.
Solubility productJEENEET
where: s = molar solubility.
Chapter 8: Redox Reactions
Equivalent massJEE
where: n = number of electrons transferred (or H⁺/OH⁻ for acid–base).
Normality–molarityJEE
where: n = n-factor of the species.
Titration formulaJEENEETCBSE
where: At endpoint of acid–base or redox titration.
Chapter 2: Solutions
Raoult's Law (ideal)JEENEETCBSE
where: Vapour pressure of an ideal binary solution.
Relative lowering of vapour pressureJEENEETCBSE
where: Colligative property.
Boiling point elevationJEENEETCBSE
where: K_b = ebullioscopic constant; i = van 't Hoff factor.
Freezing point depressionJEENEETCBSE
where: K_f = cryoscopic constant.
Osmotic pressureJEENEETCBSE
where: C = molar concentration; T in Kelvin.
van 't Hoff factorJEENEET
where: n = number of particles formed; α = degree.
Chapter 3: Electrochemistry
Standard cell EMFJEENEETCBSE
where: Both half-cells in reduction-potential convention.
Nernst equationJEENEETCBSE
where: n = electrons transferred; Q = reaction quotient.
Gibbs–EMF relationJEENEETCBSE
where: F = 96485 C/mol; n = electrons transferred.
Faraday's First LawJEENEET
where: Mass deposited at electrode; Z = electrochemical equivalent.
Conductivity ↔ molar conductivityJEENEETCBSE
where: κ in S/cm; C in mol/L; Λ_m in S·cm²/mol.
Kohlrausch's Law (limiting molar conductivity)JEENEET
where: Independent migration of ions at infinite dilution.
Chapter 4: Chemical Kinetics
Rate law (general)JEENEETCBSE
where: Order = x+y; determined experimentally.
Integrated zero-order rateJEENEET
where: k has units of mol·L⁻¹·s⁻¹.
Integrated first-order rateJEENEETCBSE
where: Half-life independent of initial concentration.
Arrhenius equationJEENEETCBSE
where: A = pre-exponential factor; E_a = activation energy.
Chapter 1: The Solid State
Density of a unit cellJEENEETCBSE
where: Z = atoms/unit cell; a = edge length; M = molar mass.
Packing efficiencyJEENEET
where: FCC/CCP = 74%, BCC = 68%, SC = 52.4%.
Edge–radius (FCC)JEENEET
where: Atoms touch along the face diagonal.
Edge–radius (BCC)JEENEET
where: Atoms touch along the body diagonal.
Chapter 5: Surface Chemistry
Freundlich adsorption isothermJEENEETCBSE
where: Empirical; log–log plot is linear.
Langmuir isothermJEE
where: Monolayer adsorption; saturates at high P.
Chapter 9: Coordination Compounds
Effective Atomic Number (EAN)JEE
where: CN = coordination number. Sidgwick's rule.
Magnetic moment (spin-only)JEENEETCBSE
where: n = unpaired electrons.
CFSE (octahedral)JEE
where: Δ_o = octahedral field splitting energy.
Chapter 10: Haloalkanes & Haloarenes
S_N1 vs S_N2 (qualitative rate law)JEENEET
where: S_N1: 3°>2°>1°·CH₃; S_N2: opposite order.
Chapter 14: Biomolecules
Specific rotationJEE
where: l = path length (dm); c = concentration (g/mL).