1. States of matter

1.1 Solids, liquids and gases

1.2 Diffusion

2. Atoms, elements and compounds

2.1 Elements, compounds and mixtures

2.2 Atomic structure and the Periodic Table

2.3 Isotopes

2.4 Ions and ionic bonds

2.5 Simple molecules and covalent bonds

2.6 Giant covalent structures

2.7 Metallic bonding

3. Stoichiometry

3.1 Formulae

3.2 Relative masses of atoms and molecules

3.3 The mole and the Avogadro constant

4. Electrochemistry

4.1 Electrolysis

4.2 Hydrogen–oxygen fuel cells

5. Chemical energetics

5.1 Exothermic and endothermic reactions

6. Chemical reactions

6.1 Physical and chemical changes

6.2 Rate of reaction

6.3 Reversible reactions and equilibrium

6.4 Redox

7. Acids, bases and salts

7.1 The characteristic properties of acids and bases

7.2 Oxides

7.3 Preparation of salts

8. The Periodic Table

8.1 Arrangement of elements

8.2 Group I properties

8.3 Group VII properties

8.4 Transition elements

8.5 Noble gases

9. Metals

9.1 Properties of metals

9.2 Uses of metals

9.3 Alloys and their properties

9.4 Reactivity series

9.5 Corrosion of metals

9.6 Extraction of metals

10. Chemistry of the environment

10.1 Water

10.2 Fertilisers

10.3 Air quality and climate

11. Organic chemistry

11.1 Formulae, functional groups and terminology

11.2 Naming organic compounds

11.3 Fuels

11.4 Alkanes

11.5 Alkenes

11.6 Alcohols

11.7 Carboxylic acids

11.8 Polymers

12. Experimental techniques and chemical analysis

12.1 Experimental design

12.2 Acid–base titrations

12.3 Chromatography

12.4 Separation and purification

12.5 Identification of ions and gases

IGCSE Chemistry 6.2 Rate of reaction Question Bank

[Maximum number: 5]

Some elements are shown in the order they appear in the reactivity series. The most reactive element is at the top.
> sodium calcium magnesium aluminium zinc iron hydrogen copper

(a)

When zinc granules are added to aqueous copper(II) sulfate, a reaction occurs. During the reaction, a red-pink solid is formed and the solution becomes colourless.

[ 5 ]

(i)

Explain, in terms of particles, why the rate of this reaction increases when the temperature is increased.

[ 3 ]

(ii)

Suggest two other ways of increasing the rate of this reaction.

1

2

[ 2 ]

[Maximum number: 1]

Which row describes the effect on the activation energy and the frequency of particle collisions when the temperature of a chemical reaction is increased?

activation

energy

frequency

of collisions

increases

no change

increases

no change

[Maximum number: 1]

Which change increases the rate of reaction by decreasing the activation energy, $E_{a}$ ?

addition of a catalyst

decrease in size of solid reactants

increase in concentration of solutions

increase in temperature

[Maximum number: 1]

Which change in reaction conditions increases both the collision rate and the proportion of molecules with sufficient energy to react?

addition of a catalyst

increasing the concentration of a reactant

increasing the surface area of a reactant

increasing the temperature of the reaction

[Maximum number: 5]

A student adds excess large pieces of magnesium carbonate, $\mathrm{MgCO}_{3}$ , to dilute hydrochloric acid, HCl , and measures the volume of carbon dioxide gas, $\mathrm{CO}_{2}$ , given off.

(a)

The graph shows how the volume of carbon dioxide gas changes with time.
volume of carbon dioxide gas

[ 5 ]

(i)

Describe how the graph shows that the rate of this reaction decreases as time increases.

[ 1 ]

(ii)

Explain, in terms of particles, why the rate of this reaction decreases as time increases.

[ 2 ]

(iii)

The student repeats the experiment using powdered $\mathrm{MgCO}_{3}$ instead of large pieces.

All other conditions stay the same.
On the grid, draw the line expected when powdered $\mathrm{MgCO}_{3}$ is used instead of large pieces.

[ 2 ]

[Maximum number: 3]

Ammonia is manufactured by the Haber process.

(a)

Explain, in terms of particles, what happens to the rate of this reaction when the temperature is increased.

[ 3 ]

[Maximum number: 1]

A student adds excess magnesium ribbon to $10 \mathrm{~cm}^{3}$ of $0.5 \mathrm{~mol} / \mathrm{dm}^{3}$ sulfuric acid.
The hydrogen gas produced is collected and its total volume is measured every 10 seconds.
The experiment is repeated with $5 \mathrm{~cm}^{3}$ of $0.5 \mathrm{~mol} / \mathrm{dm}^{3}$ sulfuric acid added to $5 \mathrm{~cm}^{3}$ of water using the same mass of magnesium ribbon.

Which line on the graph shows the results of the second experiment?

[Maximum number: 1]

An experiment is carried out to find the rate of reaction between hydrochloric acid and zinc.

\mathrm{Zn}(\mathrm{~s})+2 \mathrm{HCl}(\mathrm{aq}) \rightarrow \mathrm{ZnCl}_{2}(\mathrm{aq})+\mathrm{H}_{2}(\mathrm{~g})

The results of the experiment are shown.

What is the label on the y-axis?

amount of $\mathrm{ZnCl}_{2}$ produced

concentration of HCl

mass of Zn reacted

volume of $\mathrm{H}_{2}$ produced

[Maximum number: 1]

Magnesium powder reacts with an excess of dilute hydrochloric acid to produce hydrogen gas.
Which statements about this reaction are correct?
1 The smaller the particles of magnesium powder, the more slowly the hydrogen is produced.

2 The higher the temperature, the faster the magnesium powder disappears.
3 The lower the concentration of dilute hydrochloric acid, the faster the rate of reaction.

4 The faster the magnesium powder disappears, the faster the rate of reaction.

1 and 2

2 and 3

2 and 4

3 and 4

An excess of calcium carbonate reacts with dilute hydrochloric acid. The volume of carbon dioxide produced is measured at regular time intervals. The results are shown as experiment 1.

The experiment is repeated with only one change to the reaction conditions.
The results are shown as experiment 2 .

Which change is made in experiment 2 ?
A The concentration of the acid is increased.
B The volume of acid is increased.
C The mass of calcium carbonate is increased.
D The calcium carbonate is powdered.

0 selected

Question 1

Question 1(e)

Question 1(e)(iii)

Question 1(e)(iv)

Question 12

Question 12

Question 13

Question 2

Question 2(d)

Question 2(d)(i)

Question 2(d)(ii)

Question 2(d)(iii)

Question 2

Question 2(c)

Question 13

Question 13

Question 13

Question 13