Kinetics

Question 1

activation energy

Answer 1

min energy particles need to collide and start a reaction

Question 2

in order for a reaction to occur, particles must..

Answer 2

collide in right orientation w sufficient energy (>Ea)

Question 3

bond making

Answer 3

exothermic; releases energy

Question 4

bond breaking

Answer 4

endothermic; aborbs energy

Question 5

maxwell

Answer 5

at origin; most probable-average-Ea; area=no. of particles; don’t touch x-axis (no max energy)

Question 6

maxwell - temp

Answer 6

lower + wider graph; higher average energy. small temp=big change. more collisions + higher energy collisions

Question 7

maxwell- con + pres

Answer 7

closer; more freq collisions; same shape just higher; same proportion >Ea

Question 8

maxwell - catalyst

Answer 8

changes Ea. same amount of product faster + at lower temp. more particles have >Ea

Question 9

small temp inc = large effect

Answer 9

many more molecules collisions

with E ≥ E act

more molecules have energy greater than activation energy

Question 10

rate of reaction

Answer 10

change in con in given time

Question 11

why would a reaction still continue at a constant temp

Answer 11

Molecules gain energy (or always some molecules have E > Ea)

Due to collisions

Question 12

why do collisions decrease energy of a molecule

Answer 12

Cause some molecules to slow down or lose energy

Question 13

measure rate of reaction where a gas is produced

Answer 13

measure volume of gas / mass lost

at regular time intervals

Question 14

define ‘catalyst’

Answer 14

speeds up rate of reaction

without being used up/ chemically unchanged at the end

Question 15

how does a catalyst work

Answer 15

provides alt reaction pathway

with lower activation energy