chemical reactions and equilibrium

Question 1

collision theory

Answer 1

1) the reactant molecules must collide with each other
2)the reactant molecules must collide with sufficient energy to break the bonds within the reactants
3) the reactant molecules must collide with the correct orientation to break the bonds within the reactants

—> successful collision(energy greater than or equal to Ea)

Question 2

what does the peak on the maxwell-boltzman distribution represent

Answer 2

the kinetic energy of the most particles present in the sample

Question 3

what does the area under the curve represent on the maxwell-boltzman distribution represent

Answer 3

equal to the total number of particles in the sample.

Question 4

do any particles have a KE of 0

Answer 4

no therefore maxwell-boltzman distribution does not start at 0

Question 5

define activation energy

Answer 5

the minimum amount of energy required to generate a reaction

Question 6

how is ror measured

Answer 6

measured typically by the change in concentration of a reactant or product per unit time

Question 7

SA affecting ror

Answer 7

Increases frequency of collisions(reactants more exposed)
Increases no. successful collisions per unit time(frequency) b/w reactant particles, increasing ror

Question 8

concentration affecting ror

Answer 8

increases frequency of collisions
increases no. of successful collisions per unit time (frequency)

Question 9

pressure affecting ror(gases)

Answer 9

increases freq of collisions
increases no. of successful collisions per unit time(frequency)
this is ONLY done by decreasing the volume of container/vessel
(conversley: increase vessel leads to decrease pressure)

Question 10

temperature affecting ror

Answer 10

-increase in temp
-increase in KE of particles
-a greater proportion of particles with energy greater than or equal to the activation energy
-a greater no. successful collisions per unit time b/w(reactants)

Question 11

catalyst definition
+function+ extra info

Answer 11

-they provide an alternative reaction pathway by lowering the activation energy for a particular reaction

(function: particles on surface distort and disrupt bonds within the molecule and hence lower Ea)
homogenous: same state as reactants and products
heterogenous: diff state as reactants and products

Question 12

catalyst on ror

Answer 12

-ror will increase
-catalyst provides alternative pathway by lowering Ea
-then a greater proportion of particles have energy greater than or equal to the Ea
-therefore greater no. of successful collisions b/w reactants per unit time –> increase in ror.