Question

Why does an increase in reaction temperature generally increase the reaction rate?

Answer 1

Increasing reaction temperature increased the kinetic energy in the system. In fact, the measurement of temperature indirectly relates the relative amount of kinetic energy in a system. 
An increase in kinetic energy results in more rapid and forceful molecular collisions, thereby increasing the rate of molecular interactions (and in a fixed-volume system, the pressure increases as well!). Hence, the reaction can occur more quickly.