Home / … / G3 Pure Chemistry / O-Level Chemistry / Rate of Reactions / G3 Pure / O-Level Chemistry Rate of Reactions · question set Exit to Rate of Reactions G3 Pure / O-Level Chemistry Rate of Reactions · question set Try K324 / 6092 Rate of Reactions exam-style questions. Covers rate measurement, graphs, prescribed factors, effective collisions, catalysts, lower-activation-energy pathways, industrial and biological catalyst examples, investigations and data.
You can take this as many times as you like.
Finish and submit Time is up, but your answers have not been submitted yet. Check your connection and try again.
Try again Practise
Questions are picked at random each time you start. You'll see your score, the answers and explanations at the end. It's for practice only and doesn't count towards mastery.
Start practising Continue practising
Recent attempts History is stored only in this browser.
No completed attempts are saved yet.
Beyond the syllabus: optional enrichment that does not count towards your progress.
Previous question Go to question Next question Practice complete
Start again
This check needs JavaScript to record answers. The reviewed questions are listed below for study.
Which definition of rate (speed) of reaction is mark-scheme correct?
How quickly a reaction finishes Change in amount of reactant used up or product formed per unit time How much product is made in total The time taken for a reaction to start A gas syringe reading increases from 10 cm³ at 20 s to 34 cm³ at 50 s. What is the average rate between 20 s and 50 s?
0.80 cm³/s 1.25 cm³/s 24 cm³/s 44 cm³/s On a curved volume-of-gas vs time graph, how do you find the rate at exactly 2 minutes?
Use the total volume at 2 minutes Draw a tangent at 2 minutes and find its gradient Join the start and end of the graph and find the gradient Count how many points are on the graph Which method is suitable for measuring rate when a precipitate forms and the mixture becomes cloudy?
Measure the time taken for a marked cross to disappear when viewed through the mixture Measure the pH with a pH probe only Measure the melting point Measure the density of the beaker When comparing the effect of concentration on rate, which control variables are most important?
Keep temperature and the surface area/mass of solid (if present) the same Keep the beaker colour the same Keep the stopwatch brand the same only Keep the final volume of gas the same Which two conditions are needed for a collision to be effective (mark-scheme)?
High pressure and large surface area Correct orientation and energy $\ge E_a$ Short time and high concentration Catalyst present and low temperature Which definition of activation energy ($E_a$) is correct?
The energy released during a reaction The minimum kinetic energy needed for an effective collision The heat added to start a reaction The average kinetic energy of particles A student increases the concentration of an acid solution. Which mark-scheme idea explains the faster rate?
Particles become lighter, so they move faster There are more reactant particles per unit volume, so collisions happen more frequently per unit time The activation energy, $E_a$, becomes smaller automatically The products have more energy Why does increasing gas pressure (at constant temperature) increase rate of reaction?
Gas particles are closer together, so collisions happen more frequently per unit time Gas particles become heavier, so they react faster Gas particles gain energy, so $E_a$ decreases Pressure changes the products formed Why does powdered marble react faster than large marble chips with dilute acid (same mass, same acid)?
Powder has a larger surface area, so there are more collisions at the surface per unit time Powder has a smaller mass, so it reacts faster Powder increases the temperature of the acid Powder lowers activation energy, $E_a$ Which TWO ideas are needed for full marks when explaining why higher temperature increases rate?
Particles move faster and a larger proportion have energy $\ge E_a$ Particles move slower and all collisions become effective Activation energy increases and particles move faster Particles move faster and pressure increases Which row gives two syllabus-valid examples of catalysts?
Iron in the Haber process; nickel in hydrogenation Water in neutralisation; sodium chloride in precipitation Oxygen in combustion; hydrogen in reduction Hydrochloric acid with magnesium; carbon dioxide in photosynthesis