Rate of reaction

Which changes make the rate of reaction faster?

Feb/March 2016

Which statement concerning catalysts in chemical reactions is incorrect?

Feb/March 2016

A number of metals react with cold water or with steam.

Feb/March 2016

With manganese(IV) oxide acting as the catalyst, hydrogen peroxide, $\text{H}_2\text{O}_2$, breaks down to form water and oxygen. $2\text{H}_2\text{O}_2(aq) \rightarrow 2\text{H}_2\text{O}(l) + \text{O}_2(g)$

Feb/March 2016

The diagram illustrates the apparatus used to determine the rate of a chemical reaction. For which reaction can this apparatus be used to measure the rate?

Feb/March 2017

Copper(II) carbonate is reacted with dilute sulfuric acid. $\text{CuCO}_3(s) + \text{H}_2\text{SO}_4(aq) \rightarrow \text{CuSO}_4(aq) + \text{CO}_2(g) + \text{H}_2\text{O}(l)$ The rate of this reaction may be altered by changing the conditions. Which changes are certain to speed up this chemical reaction?

Feb/March 2017

Copper(II) carbonate is allowed to react with dilute sulfuric acid. $\text{CuCO}_3(s) + \text{H}_2\text{SO}_4(aq) \rightarrow \text{CuSO}_4(aq) + \text{CO}_2(g) + \text{H}_2\text{O}(l)$. The speed of the reaction may be altered by changing the conditions. Which changes will always make this chemical reaction faster?

Feb/March 2017

Which reaction is not influenced by the presence of light?

Feb/March 2017

A student carries out an investigation on two acids W and X. Equal volumes of W and X are reacted separately with excess magnesium. The student records these observations. 1 Hydrogen gas is produced more quickly with W than with X. 2 The final volume of hydrogen gas produced is the same for both acids. Which statement accounts for these observations?

Feb/March 2017

Magnesium carbonate was mixed with dilute hydrochloric acid in a conical flask. The conical flask was set on a balance, and the mass of the conical flask and its contents was measured as the reaction continued. As the reaction took place, carbon dioxide gas was given off. The reaction was carried out at two different temperatures. Which row is correct?

Feb/March 2018

In which reaction is the reaction rate unaffected by light?

Feb/March 2018

When calcium carbonate is added to dilute hydrochloric acid, bubbles of carbon dioxide are produced. If the temperature is raised, this reaction happens more quickly. Which row gives the correct explanation for this observation?

Feb/March 2018

Chunks of limestone react with dilute hydrochloric acid as represented by the equation below. $\text{CaCO}_3 + 2\text{HCl} \rightarrow \text{CaCl}_2 + \text{H}_2\text{O} + \text{CO}_2$. Which alteration in the conditions would decrease the rate of reaction?

Feb/March 2019

A student records how long $2.0\,\text{g}$ of magnesium takes to dissolve in $50\,\text{cm}^3$ of dilute sulfuric acid. Which piece of apparatus is needed for this experiment?

Feb/March 2019

A student puts dilute hydrochloric acid at two different temperatures onto two separate lumps of limestone. The limestone lumps each have the same mass. The carbon dioxide gas formed is gathered in a gas syringe. The volume of carbon dioxide collected in 1 minute at each temperature is shown. Which row gives the description and explanation of the results at $50^{\circ}\text{C}$ compared with $25^{\circ}\text{C}$?

Feb/March 2019

A student carried out an investigation into the reaction of zinc with dilute hydrochloric acid by recording the volume of hydrogen gas produced at 1 minute intervals. $\text{Zn} + 2\text{HCl} \rightarrow \text{ZnCl}_2 + \text{H}_2$

Feb/March 2019

Marble chips (calcium carbonate) undergo reaction with hydrochloric acid in an exothermic reaction. $\text{calcium carbonate} + \text{hydrochloric acid} \rightarrow \text{calcium chloride} + \text{water} + \text{carbon dioxide}$ If excess marble chips are placed into dilute hydrochloric acid, the reaction begins rapidly, then becomes slower until it comes to a stop. Why does the reaction rate become slower?

Feb/March 2020

A student places excess magnesium ribbon into $10\text{ cm}^3$ of $0.5\ \text{mol dm}^{-3}$ sulfuric acid. The hydrogen gas is collected, and its volume is recorded at intervals of 10 seconds. The experiment is then carried out again with the same mass of magnesium ribbon, but this time $5\text{ cm}^3$ of $0.5\ \text{mol dm}^{-3}$ sulfuric acid is mixed with $5\text{ cm}^3$ of water. Which graph shows the results of the second experiment?

Feb/March 2020

This question concerns the reactions of magnesium with nitric acid.

Feb/March 2020

The apparatus illustrated is used to determine the rate of a reaction. Which equation shows a reaction whose rate can be measured with this apparatus?

Feb/March 2021

The apparatus illustrated is used for measuring the rate of a reaction. Which equation shows a reaction for which this apparatus can be used to measure the rate?

Feb/March 2021

A student examines the reaction between magnesium powder and dilute hydrochloric acid. Magnesium is present in excess. $\text{Mg} + 2\text{HCl} \rightarrow \text{MgCl}_2 + \text{H}_2$ The reaction rate can be determined by tracking the rise in hydrogen volume with time. The graph shows the results.

Feb/March 2021

The reaction between the aqueous compounds X and Y is slow and exothermic. The graph illustrates how the rate of this reaction varies over time. A student proposes that the reaction rate falls with time because:

Feb/March 2023

Hydrogen combines with iodine to produce hydrogen iodide. $\text{H}_2(g) + \text{I}_2(g) \rightarrow 2\text{HI}(g)$ Which statements account for the reaction being faster when the pressure is raised, while the temperature remains constant?

Feb/March 2023

A student looks at how iron powder reacts with dilute hydrochloric acid at 20 ^{\circ}C. The hydrochloric acid is in excess.

Feb/March 2023

In two separate experiments, an excess of calcium carbonate is added to $50\,\text{cm}^3$ of dilute hydrochloric acid at different concentrations. The volume of gas formed in experiment 1 and experiment 2 is recorded at 30-second intervals. The results are given in the table. Which diagram shows the data collected?

Feb/March 2024

An experiment is arranged as shown. The mass of the conical flask and its contents is recorded every 30 seconds. Which statement about the reaction and the changes made to the reaction conditions is correct?

Feb/March 2024

Which statement gives the definition of the activation energy, $E_a$, for a reaction?

Feb/March 2024

In experiment 1, small pieces of limestone are placed into dilute ethanoic acid at $40\,^{\circ}\text{C}$. The volume of carbon dioxide given off is recorded at fixed time intervals. The results are plotted on a graph. Which changes produce the results shown in experiment 2?

Feb/March 2024

A sample of calcium carbonate is made to react with dilute hydrochloric acid, giving a final gas volume of $60\,\text{cm}^3$. The reaction ends after $120\,\text{s}$. The experiment is then carried out again at a lower temperature, while every other condition remains unchanged. Which row gives the outcomes for the second experiment?

Feb/March 2025

Which statements account for why raising the temperature in a reaction involving gases increases the rate of reaction?

Feb/March 2025

A student explores how magnesium reacts with dilute sulfuric acid.

Feb/March 2025

A liquid X reacts with solid Y to produce a gas. Which two diagrams show appropriate methods for investigating the reaction rate (speed)?

May/June 2016

In experiment S, hydrogen volume is measured when excess dilute sulfuric acid is added to zinc. A second experiment, T, uses the same mass of zinc but under different conditions. The outcomes of the two experiments are shown. Which changes in conditions between experiments S and T produce curve T?

May/June 2016

A liquid $X$ is reacted with solid $Y$ to produce a gas. Which two diagrams show appropriate methods for investigating the reaction rate (speed)?

May/June 2016

The outcomes of two distinct reactions involving excess calcium carbonate and hydrochloric acid are shown. Which statement accounts for the differences between the reactions?

May/June 2016

When liquid X reacts with solid Y, a gas is produced. Which two diagrams show suitable ways of investigating the rate (speed) of this reaction?

May/June 2016

Magnesium is allowed to react with a dilute acid. The hydrogen gas produced is collected, and its volume is measured. The results are displayed on the graph. Between which times was the reaction fastest?

May/June 2016

A liquid X reacts with solid Y to produce a gas. Which two diagrams display appropriate methods for studying the rate (speed) of the reaction?

May/June 2016

Which statements account for the fact that a higher temperature increases the rate of a chemical reaction?

May/June 2016

The equation for an exothermic reaction in the Contact process is given below. $2\text{SO}_2(g) + \text{O}_2(g) \rightarrow 2\text{SO}_3(g)$ How do increasing the temperature and adding a catalyst affect the rate at which sulfur trioxide, $\text{SO}_3$, is formed?

May/June 2016

Liquid X reacts with solid Y and produces a gas. Which two diagrams show appropriate ways to investigate the rate (speed) of the reaction?

May/June 2016

Which row shows how the energy associated with collisions between particles changes when concentration and temperature are both increased?

May/June 2016

A liquid $X$ reacts with a solid $Y$ to produce a gas. Which two diagrams show suitable ways to investigate the rate (speed) of the reaction?

May/June 2016

Which row correctly explains why a rise in temperature increases the rate of reaction?

May/June 2016

Dilute hydrochloric acid reacts with calcium carbonate. $CaCO_3(s) + 2HCl(aq) \rightarrow CaCl_2(aq) + CO_2(g) + H_2O(l)$ A student studied the reaction by recording the volume of carbon dioxide given off each minute while the temperature stayed constant.

May/June 2016

When hydrochloric acid reacts with magnesium, the products formed are aqueous magnesium chloride and hydrogen. $\text{Mg}(s) + 2\text{HCl}(aq) \rightarrow \text{MgCl}_2(aq) + \text{H}_2(g)$

May/June 2016

Using the apparatus shown, a student studied the reaction of zinc with sulfuric acid at $20\,^{\circ}\text{C}$. Zinc was present in excess.

May/June 2016

When aqueous sodium thiosulfate is combined with dilute hydrochloric acid, insoluble sulfur forms as a precipitate. This causes the mixture to become hard to see through. $\text{Na}_2\text{S}_2\text{O}_3(aq) + 2\text{HCl}(aq) \rightarrow \text{S}(s) + 2\text{NaCl}(aq) + \text{H}_2\text{O}(l) + \text{SO}_2(g)$ The length of time for the cross to vanish from sight is measured.

May/June 2016

A student investigated the reaction of marble chips with dilute hydrochloric acid. Which changes reduce the rate of reaction?

May/June 2017

A student was carrying out an investigation into the reaction between marble chips and dilute hydrochloric acid. Which changes would make the rate of reaction slower?

May/June 2017

A student was examining the reaction between marble chips and dilute hydrochloric acid. Which alterations reduce the rate of reaction?

May/June 2017

A student was carrying out an investigation into the reaction of marble chips with dilute hydrochloric acid. Which changes would decrease the rate of reaction?

May/June 2017

A student was carrying out an investigation into the reaction between marble chips and dilute hydrochloric acid. Which changes would reduce the rate of reaction?

May/June 2017

A student was carrying out an investigation into the reaction between marble chips and dilute hydrochloric acid. Which changes would make the rate of reaction slower?

May/June 2017

A student investigated how the volume of gas changed as a reaction went on after adding a small mass of powdered barium carbonate to an excess of 0.1 mol/dm$^3$ hydrochloric acid. The reaction between barium carbonate and dilute hydrochloric acid produces carbon dioxide gas, and a graph was then plotted from the results.

May/June 2017

The diagram illustrates an experiment on rate of reaction. Raising the concentration of the acid and raising the temperature each influence the rate of reaction. Which row is correct?

May/June 2018

The diagram illustrates an experiment on rate of reaction. Raising the concentration of the acid and increasing the temperature both influence the rate of reaction. Which row is correct?

May/June 2018

The diagram illustrates a rate of reaction experiment. Raising the acid concentration and raising the temperature each change the rate of reaction. Which row is correct?

May/June 2018

Which row gives the effect of raising both concentration and temperature on collisions between reacting particles?

May/June 2018

Which row shows how raising both concentration and temperature affects the collisions between reacting particles?

May/June 2018

Which row states the effects of raising both concentration and temperature on collisions between reacting particles?

May/June 2018

Hydrogen gas forms when zinc reacts with hydrochloric acid. The graph shows how the volume of hydrogen gas produced varies with time when excess zinc is reacted with $0.2\,\text{mol dm}^{-3}$ hydrochloric acid.

May/June 2018

This apparatus is used to study the rate at which calcium carbonate reacts with hydrochloric acid at $30\,^\circ\text{C}$.

May/June 2018

Hydrogen peroxide solution breaks down very slowly at room temperature, giving oxygen gas. When liquid detergent is added, this gas produces a foam that rises. Five test-tubes are each half-filled with hydrogen peroxide solution. A drop of liquid detergent is then added to every tube. Different metal oxides are added to four of the test-tubes, and the height of the foam produced after 1 minute is measured. The results are shown. Which conclusion can be drawn from these results?

May/June 2019

The experiment is arranged as shown. Every 30 seconds, the mass of the conical flask and its contents is recorded. Which option correctly describes the reaction and the changes to the reaction conditions?

May/June 2019

A student reacts strips of zinc with dilute sulfuric acid and records how long it takes to produce $100\,\text{cm}^3$ of hydrogen. The test is repeated under different conditions. The results are shown in the table. Which change in conditions would give the results shown in experiment 2?

May/June 2019

Which change to the reaction conditions raises both the collision frequency and the proportion of molecules that have enough energy to react?

May/June 2019

Which alteration to the reaction conditions raises both the collision frequency and the proportion of molecules that have enough energy to react?

May/June 2019

Which alteration to the reaction conditions raises both the collision frequency and the fraction of molecules that have enough energy to react?

May/June 2019

A student studies the rate of reaction when small pieces of calcium carbonate react with an excess of hydrochloric acid at a concentration of $1\,\text{mol dm}^{-3}$. $\text{CaCO}_3(s) + 2\text{HCl}(aq) \rightarrow \text{CaCl}_2(aq) + \text{CO}_2(g) + \text{H}_2\text{O}(l)$

May/June 2019

A student looks into the rate of reaction between magnesium ribbon and an excess of dilute hydrochloric acid. $\text{Mg} + 2\text{HCl} \rightarrow \text{MgCl}_2 + \text{H}_2$

May/June 2019

A student examines how quickly large pieces of magnesium carbonate react with an excess of dilute nitric acid. $\text{MgCO}_3 + 2\text{HNO}_3 \rightarrow \text{Mg(NO}_3)_2 + \text{CO}_2 + \text{H}_2\text{O}$

May/June 2019

Zinc reacts with an acid, giving off a gas. The gas volume is recorded at regular time intervals. The outcomes are displayed by curve Z. The experiment is carried out again with a catalyst present. Which curve represents the catalysed reaction?

May/June 2021

An excess amount of calcium carbonate is allowed to react with dilute hydrochloric acid. At fixed time intervals, the volume of carbon dioxide formed is recorded. The findings are given for experiment 1. The experiment is then carried out again, with just one alteration to the reaction conditions. The findings for experiment 2 are shown. What alteration has been made in experiment 2?

May/June 2021

Copper(II) carbonate reacts with dilute sulfuric acid. Which conditions would give the highest rate of reaction?

May/June 2021

Four statements concerning the effect of a rise in temperature on a reaction are given. Which of the statements are correct?

May/June 2021

An excess of calcium carbonate is allowed to react with dilute hydrochloric acid. Carbon dioxide formed is recorded at equal time intervals. These findings are given for experiment 1. The experiment is then carried out again, with just one alteration to the reaction conditions. The findings are given for experiment 2. Which alteration is made in experiment 2?

May/June 2021

Four statements about the effect of increasing temperature on a reaction are shown. Which of the statements are correct?

May/June 2021

Four statements describing the effect of increasing temperature on a reaction are given. Which of these statements are correct?

May/June 2021

State what the term thermal decomposition means.

May/June 2021

Name a rock that is composed mainly of calcium carbonate.

May/June 2021

Cement is produced by heating together calcium carbonate and powdered clay.

May/June 2021

A fixed volume of hydrochloric acid is reacted with excess magnesium ribbon, and the volume of gas released is recorded as time passes. The outcomes of two separate experiments are shown. Which statement accounts for the differences in the results from the two experiments?

May/June 2022

A student records how long it takes for $2.0\,\text{g}$ of magnesium to dissolve in $50\,\text{cm}^3$ of dilute sulfuric acid. Which piece of apparatus is needed to carry out the experiment?

May/June 2022

Which of the following statements about rate of reaction is correct?

May/June 2022

A student records how long it takes for 2.0 g of magnesium to dissolve in 50 cm$^3$ of dilute sulfuric acid. Which apparatus is needed to carry out the experiment?

May/June 2022

The reaction rate for zinc lumps reacting with dilute sulfuric acid is investigated. The test is carried out four times, with just one variable altered on each occasion. The alterations are shown below. 1. The zinc lumps are changed to powdered zinc. 2. Water is mixed with the dilute sulfuric acid. 3. The temperature of the dilute sulfuric acid is raised. 4. A catalyst is introduced into the reaction mixture. Which of these alterations cause the reaction rate to increase?

May/June 2022

A student records how long it takes for $2.0\,\text{g}$ of magnesium to dissolve in $50\,\text{cm}^3$ of dilute sulfuric acid. Which piece of apparatus is needed to carry out the experiment? 1 stop-clock 2 measuring cylinder 3 thermometer 4 balance

May/June 2022

A student records how long $2.0\,\text{g}$ of magnesium takes to dissolve in $50\,\text{cm}^3$ of dilute sulfuric acid. Which apparatus must be used to carry out the experiment?

May/June 2022

Which statements account for why raising the concentration of a reactant increases the reaction rate?

May/June 2022

A student records how long $2.0\,\text{g}$ of magnesium takes to dissolve in $50\,\text{cm}^3$ of dilute sulfuric acid. Which piece of apparatus is needed to carry out this experiment?

May/June 2022

Which statement gives the reason that a higher reactant concentration raises the reaction rate?

May/June 2022

A student times how long $2.0\,\text{g}$ of magnesium takes to dissolve in $50\,\text{cm}^3$ of dilute sulfuric acid. Which apparatus is required to carry out the experiment?

May/June 2022

A student examines how large chunks of copper(II) carbonate react with dilute hydrochloric acid. The hydrochloric acid is present in excess. $\text{CuCO}_3 + 2\text{HCl} \rightarrow \text{CuCl}_2 + \text{CO}_2 + \text{H}_2\text{O}$ The reaction rate is determined by tracking the mass of the reaction mixture as time passes. The outcomes are displayed on the graph.

May/June 2022

A learner studies how tiny pieces of calcium carbonate react with dilute hydrochloric acid. The hydrochloric acid is in excess. $\text{CaCO}_3 + 2\text{HCl} \rightarrow \text{CaCl}_2 + \text{CO}_2 + \text{H}_2\text{O}$ The reaction rate is determined by recording the volume of carbon dioxide gas produced as time passes. The graph shows the results.

May/June 2022

A student carries out an investigation into how quickly aqueous hydrogen peroxide decomposes, using 0.2 g of a catalyst. $2\text{H}_2\text{O}_2 \rightarrow 2\text{H}_2\text{O} + \text{O}_2$ The rate of the reaction is determined by recording the volume of oxygen gas formed as time passes. The graph displays the results.

May/June 2022

Pieces of calcium carbonate react with dilute hydrochloric acid, as shown. $\text{CaCO}_3 + 2\text{HCl} \rightarrow \text{CaCl}_2 + \text{H}_2\text{O} + \text{CO}_2$ Which change in the conditions would lower the rate of the reaction?

May/June 2023

Which of these changes make the rate of reaction faster? 1 raising the concentration of the reactants 2 making the particle size of a solid reactant larger 3 raising the temperature

May/June 2023

Which row shows the changes that all make the rate of a chemical reaction increase?

May/June 2023