Govt Exams
Activation energy is the minimum energy required for reactants to overcome the energy barrier and form products. It is always positive and independent of temperature.
The units s⁻¹ or time⁻¹ indicate a first-order reaction. For first-order reactions, the rate constant has units of time⁻¹.
For a zero-order reaction, t₁/₂ = [A]₀/(2k), which is directly proportional to initial concentration.
The color of the reaction vessel does not affect the reaction rate. Temperature, nature of reactants, concentration, pressure, and catalyst are actual factors affecting reaction rate.
Color of a solution is a physical property unrelated to ionic conductance. Conductance depends on nature of solute, concentration, temperature, and solvent.
The electrochemical series arranges elements in order of their standard reduction potentials, with more positive values indicating stronger oxidizing agents.
Conductivity increases with temperature because ionic mobility increases due to decreased viscosity of the medium.
SHE (Standard Hydrogen Electrode) is the arbitrary reference against which all other reduction potentials are measured.
Anode undergoes oxidation (Zn → Zn²⁺ + 2e⁻), losing mass. Cathode undergoes reduction (Cu²⁺ + 2e⁻ → Cu), gaining mass.
At cathode: Na⁺ + e⁻ → Na (reduction). At anode: 2Cl⁻ → Cl₂ + 2e⁻ (oxidation).