AQA GCSE 9-1 higher combined science - chemistry paper 2 All Answers
Correct
1. How do we measure the speed of a chemical reaction?
Answer: We measure the rate of reaction by calculating the quantity of reactant used up or product
formed over a specific period of time.
2. What is the typical unit used to measure time when calculating the rate of reaction?
Answer: We typically use seconds as the unit of time when measuring the rate of reaction.
3. What is the usual unit used to measure mass when calculating the rate of reaction?
Answer: Grams are usually used as the unit of mass when measuring the rate of reaction.
4. What is the typical unit used to express the rate of reaction?
Answer: The rate of reaction is typically expressed in grams per second (g/s).
5. How can we also determine the rate of reaction?
Answer: We can also determine the rate of reaction by analyzing a graph that plots the quantity of
reactant used up or product formed against time.
6. How do we calculate the gradient of a graph to determine the rate of reaction?
Answer: We calculate the gradient by dividing the change in y (the quantity of reactant used up or
product formed) by the change in x (time).
7. What factors can influence the rate of a chemical reaction?
, Answer: Temperature, pressure, concentration, surface area, and catalysts are key factors that can
affect the rate of a chemical reaction.
8. What happens to the rate of reaction when temperature increases?
Answer: The rate of reaction typically increases as temperature increases, as molecules gain more
energy and collide more frequently.
9. What is concentration a measurement of, and how does it impact the rate of reaction?
Answer: Concentration measures the number of particles dissolved in a given volume of solvent, and
increasing concentration can increase the frequency of collisions between particles, resulting in a faster
rate of reaction.
10. What happens to the rate of reaction when pressure or concentration is increased?
Answer: Increasing pressure or concentration can increase the frequency of collisions between particles,
resulting in a faster rate of reaction.
11. What is a catalyst, and how does it work?
Answer: A catalyst is a substance that speeds up a chemical reaction without being consumed or altered
during the process. It works by decreasing the activation energy required for a reaction to occur.
12. According to collision theory, what must happen for chemical reactions to take place?
Answer: Chemical reactions can only take place if particles collide into each other with sufficient energy.
13. What happens when concentration, pressure, or surface area is increased, according to collision
theory?
Correct
1. How do we measure the speed of a chemical reaction?
Answer: We measure the rate of reaction by calculating the quantity of reactant used up or product
formed over a specific period of time.
2. What is the typical unit used to measure time when calculating the rate of reaction?
Answer: We typically use seconds as the unit of time when measuring the rate of reaction.
3. What is the usual unit used to measure mass when calculating the rate of reaction?
Answer: Grams are usually used as the unit of mass when measuring the rate of reaction.
4. What is the typical unit used to express the rate of reaction?
Answer: The rate of reaction is typically expressed in grams per second (g/s).
5. How can we also determine the rate of reaction?
Answer: We can also determine the rate of reaction by analyzing a graph that plots the quantity of
reactant used up or product formed against time.
6. How do we calculate the gradient of a graph to determine the rate of reaction?
Answer: We calculate the gradient by dividing the change in y (the quantity of reactant used up or
product formed) by the change in x (time).
7. What factors can influence the rate of a chemical reaction?
, Answer: Temperature, pressure, concentration, surface area, and catalysts are key factors that can
affect the rate of a chemical reaction.
8. What happens to the rate of reaction when temperature increases?
Answer: The rate of reaction typically increases as temperature increases, as molecules gain more
energy and collide more frequently.
9. What is concentration a measurement of, and how does it impact the rate of reaction?
Answer: Concentration measures the number of particles dissolved in a given volume of solvent, and
increasing concentration can increase the frequency of collisions between particles, resulting in a faster
rate of reaction.
10. What happens to the rate of reaction when pressure or concentration is increased?
Answer: Increasing pressure or concentration can increase the frequency of collisions between particles,
resulting in a faster rate of reaction.
11. What is a catalyst, and how does it work?
Answer: A catalyst is a substance that speeds up a chemical reaction without being consumed or altered
during the process. It works by decreasing the activation energy required for a reaction to occur.
12. According to collision theory, what must happen for chemical reactions to take place?
Answer: Chemical reactions can only take place if particles collide into each other with sufficient energy.
13. What happens when concentration, pressure, or surface area is increased, according to collision
theory?
