speed of reaction !

Question 1

factors : concentration of reactants in solution

Answer 1

• the greater the concentration -> more particles per unit volume -> increase in frequency of effective collisions -> increases speed of reaction

Question 2

factors : pressure of gaseous reactants

Answer 2

• the greater the pressure -> more particles per unit volume -> increases frequency of effective collisions -> increases speed of reaction

Question 3

factors : particle size of solid reactants

Answer 3

• the smaller the size of the particle -> greater surfaces area to volume ratio -> increases frequency of effective collisions -> increases speed of reaction

Question 4

factors : temperature

Answer 4

• the higher the temperature -> the greater the kinetic energy the particles posses -> more particles have energy equal or greater to the activation energy -> increased frequency of effective collisions -> speed of reaction increases

Question 5

factors : presence of catalyst

Answer 5

• provides an alternative pathway with lower activation energy -> more particles with energy equal or greater than activation energy -> increases frequency of effective collisions -> speed of reaction increases

Question 6

measuring SOR ! p1

Answer 6

change in mass of reaction mixture with time

- time taken for a fixed mass of reaction mixture to be lost

Question 7

measuring SOR ! p1.5

Answer 7

cotton wool : allows gas to escape + prevent acid spray

no stopper : pressure built up due to gas produced can cause the stopper to pop / flask to crack

Question 8

measuring SOR ! p2

Answer 8

measuring volume of gas produced

- time taken for a fixed volume of gas to be collected

Question 9

experimental error !

Answer 9

human reaction time

1. delay in start time due to coordination of starting stopwatch & transferring carbonate to acid
   - time taken is shorter than actual
2. stopwatch started earlier due to coordination of starting stopwatch & transferring carbonate to acid
   - time taken is longer than actual