speed of reaction 🚤

Question 1

how to measure speed of reaction

Answer 1

how quickly a reactant is used up or how quickly a product is formed - time for completion, volume of gas evolved, mass of reaction mixture at regular time intervals

Question 2

factors affecting rate of reaction

Answer 2

1) particle size
2) concentration (liquid)
3) basicity of acid
4) pressure (gas)
5) temperature
6) presence of catalyst

Question 3

how does a smaller particle size increase rate of reaction?

Answer 3

when particle size of a reactant increases, the total surface area of the reactant increases. thus, there is a larger total surface area exposed for the other reacting particles to collide with at any one time. frequency of effective collision between reacting particles increases and rate of reaction increases

Question 4

how does a higher concentration increase rate of reaction?

Answer 4

when concentration of a reactant increases, the number of reacting particles per unit volume increases. frequency of effective collision between reacting particles increases and rate of reaction increases

Question 5

in what case will concentration affect yield?

Answer 5

when the reactant is the limiting reactant

Question 6

how does a higher basicity increase rate of reaction? (sulfuric acid instead of hydrochloric acid)

Answer 6

sulfuric acid is dibasic while hydrochloric acid is monobasic. for the same concentration of sulfuric acid, the concentration of hydrogen ions in sulfuric acid is twice that in hydrochloric acid, hence reaction is faster

Question 7

how does an increase in pressure increase rate of reaction?

Answer 7

when pressure of reaction mixture is increased, the number of reacting particles per unit volume increases. frequency of effective collisions increases and rate of reaction increases

Question 8

how does an increase in temperature increase rate of reaction?

Answer 8

when the temperature of a reaction mixture is increased, reacting particles gain kinetic energy and move faster. there is an increase in the number of reacting particles with energy greater than or equal to activation energy. frequency of effective collision between reacting particles increases and rate of reaction increases

Question 9

how does the presence of a catalyst increase rate of reaction?

Answer 9

catalyst provides an alternative pathway for the reaction to occur with a lower activation energy. number of reacting particles with energy greater than or equal to activation energy increases. frequency of effective collision increases and rate of reaction increases