Pressure is increased if you heat something, because the increase in temperature causes the molecules to move faster and collide more.
It is a density dependent limiting factor
d electroniCred ca da este hidrogenul si oxigenul isi pier
The activation energy as per the definition given by Svante Arrhenius is the minimum amount of energy that is needed for the chemical reaction to proceed. If the amount of the activation energy is decreased then, the reaction would be completed faster.