Altering Factors

Question 1

What five factors can affect reaction rate?

Answer 1

. Temperature
. Concentration
. Particle Size
. Pressure
. Use of a catalyst

Question 2

Why does a higher temperature result in faster reaction?

Answer 2

. By increasing the temperature, the particles have more energy and so move more quickly and ‘violently’. This causes more collisions to take place and the reaction rate is increased.
. Higher temperature = faster rate of reaction
. Increase of 10 degrees often doubles the rate of reaction

Question 3

Why do powdered solids react faster than lumps?

Answer 3

. By increasing the particle size, we are increasing its surface area. This increases the surface area that collisions can take place on.
. Greater surface area = faster rate of reaction

Question 4

Why does a higher concentration result in a faster reaction?

Answer 4

. By increasing the concentration of reactants there are more reactant particles moving together. This causes more collisions to take place and the reaction rate is increased
. Higher concentration of reactants = Faster rate of reaction

Question 5

Why does a higher pressure result in a faster reaction?

Answer 5

. By increasing the pressure of gaseous reactants, there are more reactant particles for a given volume. This causes more collisions to take place and the reaction rate is increased
. Higher pressure = faster rate of reaction