Amounts and solutions
n = m/M; c = n/V; C₁V₁ = C₂V₂ for ideal dilution of the same solute; percent yield = actual/theoretical × 100%.
Gases and energy
PV = nRT; q = mcΔT; ΔG = ΔH − TΔS; pH = −log₁₀[H⁺]. Use absolute temperature in kelvin for gas and thermodynamic equations.