KINETICS I

Question 1

ACTIVATION ENERGY

Answer 1

the minimum
energy which particles need to collide to start a reaction

Question 2

Effect of Increasing Concentration and Increasing Pressure

Answer 2

At higher concentrations(and pressures) there are more particles per unit volume and so the particles collide with a greater frequency
and there will be a higher frequency of effective collisions. If concentration increases, the shape of the energy distribution curves do not change (i.e. the peak is at the same energy) so the Emp and mean energy do not
change. They curves will be higher, and the area under the curves will
be greater because there are more particles.

Question 3

Effect of Increasing Temperature

Answer 3

At higher temperatures the energy of the particles increases. They collide more frequently and more often with energy greater than the activation energy. More collisions result in a reaction. As the temperature increases, the graph shows that a significantly bigger proportion of particles have energy greater than the activation energy, so the frequency of successful collisions increases.

Question 4

Effect of Increasing Surface Area

Answer 4

Increasing surface area will cause successful collisions to occur more frequently between the reactant particles and this increases the rate of the reaction.

Question 5

catalysts

Answer 5

they increase reaction rates without getting used up. they do this by providing an alternative route or mechanism with a lower activation energy.