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The Arrhenius equation k = Ae^(-Ea/RT) quantifies how rate constant depends on temperature. A = pre-exponential factor (collision frequency x orientation factor). Ea = activation energy (minimum energy for reaction). Logarithmic form: ln(k) = ln(A) - Ea/(RT). Plot ln(k) vs 1/T: straight line, slope = -Ea/R. Two-temperature form: ln(k2/k1) = (Ea/R)(1/T1 - 1/T2) — most useful for JEE calculations. Temperature coefficient = k_(T+10)/k_T ≈ 2-3 for most reactions near room temperature. This corresponds to Ea ≈ 50-55 kJ/mol. Higher Ea means stronger temperature sensitivity (steeper Arrhenius plot). At T -> infinity: k -> A. At T = 0: k = 0. The fraction of molecules with E >= Ea follows the Boltzmann distribution: e^(-Ea/RT). A small temperature increase dramatically increases this fraction because it's in the exponential tail. For a 10 K increase from 300 to 310 K with Ea = 50 kJ/mol: k increases by about 2x. With Ea = 100 kJ/mol: k increases by about 4x. This explains why temperature control is critical in industrial chemistry and why enzyme-catalysed reactions are so sensitive to fever.