Q.1
Increasing the temperature of the reactants in a chemical reaction increases the rate of the chemical reaction. This is because...
  • particles collide less often, but they have more energy
  • particles collide more often and they collide with less energy
  • particles collide more often and they collide with more energy
  • particles collide less often with less energy
Q.2
Around room temperature, if we increase the temperature of a reaction by 10°C, the rate of the reaction will approximately...
  • halve
  • triple
  • stay the same
  • double
Q.3
Why does increasing the concentration of reactants increase the rate of a reaction?
  • If the concentration of reactants is increased, there are more particles available to react
  • If the concentration of reactants is increased, the particles have more energy
  • If the concentration of reactants is increased, there are fewer particles available to react
  • If the concentration of reactants is increased, the particles are at the right angle to collide
Q.4
How does increasing the pressure increase the rate of a chemical reaction?
  • If the pressure is increased, the particles are further away from each other
  • If the pressure is increased, the particles are moving faster
  • If the pressure is increased, the particles have more energy
  • If the pressure is increased, the particles are closer together
Q.5
A catalyst speeds up a chemical reaction by...
  • reducing the amount of energy required by the particles to react
  • increasing the amount of energy required by the particles to react
  • increasing the pressure of the reactants
  • increasing the temperature of the reactants
Q.6
If the surface area of a solid reactant is increased, why is the rate of reaction increased?
  • There are fewer particles on the surface of the solid available to react
  • There are more particles on the surface of the solid available to react
  • The particles are moving more quickly
  • The particles have more energy
Q.7
Scientists have developed catalysts that enable reactions to take place at lower temperatures. Why is this advantageous to the manufacturer and the environment?
  • It is cheaper for the manufacturer because less fuel is needed to provide the high temperatures It is better for the environment because there is less fuel being burnt and so less carbon dioxide being emitted
  • It is better for the manufacturer because catalysts are cheap to buy It is better for the environment because the catalyst does not harm the environment
  • It is better for the manufacturer because the catalyst can be reused It is better for the environment because there are more toxic gases being released
  • It is better for the manufacturer because the catalyst is often very expensive It is better for the environment because there are fewer toxic emissions
Q.8
Chemical reactions eventually stop. What is the usual reason for this?
  • Reactants run out
  • Catalyst runs out
  • Particles have used up all their energy
  • Products have taken the particles' energy
Q.9
Why can icing sugar cause an explosion but sugar lumps can't?
  • The icing sugar has more energy
  • The icing sugar has more particles
  • The icing sugar has a larger surface area
  • The sugar lumps have more energy
Q.10
Some chemical reactions may take place twice as quickly if their temperature is raised by 10°C. If a particular reaction takes 32 minutes at 20°C, how long will it take if the temperature is raised to 60°C?
  • 2 minutes
  • 4 minutes
  • 6 minutes
  • 8 minutes
0 h : 0 m : 1 s