Define the following terms:
$1.$ Collision
$2.$ Frequency of collision

The plot of $\log k_f$ versus $1 / T$ for a reversible reaction $A_{(g)} \rightleftharpoons P_{(g)}$ is shown. Pre-exponential factors for the forward and backward reactions are $10^{15} \ s^{-1}$ and $10^{11} \ s^{-1}$,respectively. If the value of $\log K$ for the reaction at $500 \ K$ is $6$,the value of $|\log k_b|$ at $250 \ K$ is $\qquad$ $[K = \text{equilibrium constant of the reaction}, k_f = \text{rate constant of forward reaction}, k_b = \text{rate constant of backward reaction}]$

Why does the rate of a reaction increase with a rise in temperature?

For a chemical reaction $A \rightarrow B$,the activation energy in the forward direction is $E_a$. Then the activation energy in the reverse direction is.........

What is the value of the slope in the graph of $\log_{10} K$ against $\frac{1}{T}$?

For an endothermic reaction $X \rightarrow Y$,the activation energies for the forward and backward reactions are $E_f$ and $E_b$ respectively. Then,in general: