10 questions · 110 marks · ≈ 2 hours
The diagram shows how the particles are arranged in the three states of matter. melting X Z Y solid liquid gas
Use words from the box to identify the changes of state X, Y and Z. condensing cooling crystallising diffusing evaporating freezing heating X Y Z
Describe the differences in the movement of particles in solids and gases.
This question is about gases in the atmosphere.
Name the most abundant gas in the atmosphere.
Name the noble gas that makes up about 1% of the atmosphere.
Name a greenhouse gas in the atmosphere.
A student uses this apparatus to determine the percentage of oxygen in a sample of air. wet iron wool column of air water This is the student’s method.
State the appearance of the iron wool after one week.
Use the student’s results to show that the percentage of oxygen in the sample of air is approximately 18%.
The actual percentage of oxygen in air is approximately 21%. Give a reason why the percentage of air calculated from the student’s results is less than 21%.
This question is about alkanes.
An alkane has the structural formula CH₃CH₂CH₂CH₃ Give the missing information for this alkane. structural formula CH₃CH₂CH₂CH₃ name C₄H₁₀ empirical formula CnH2n+2
There are two isomers of C₄H₁₀
State what is meant by the term isomers.
Draw the displayed formula of each isomer of C₄H₁₀ Isomer 1 Isomer 2
Methane reacts with bromine to form bromomethane and one other product.
Give the formula of the other product.
What is the name of this type of reaction?
Choose your answer
addition
decomposition
neutralisation
substitution
State the condition needed for this reaction to occur.
When ethane (C₂H₆ ) burns in a plentiful supply of air, carbon dioxide and water are formed.
Give a chemical equation for this reaction.
When the air supply is limited, incomplete combustion occurs. Explain why a gas formed by incomplete combustion can cause a problem for humans.
A student investigates the effect of temperature on the rate of reaction between two solutions, A and B. When the reaction occurs, the mixture turns from colourless to blue. This is the student’s method.
Give two variables that the student needs to keep constant in this investigation. 1 2
The table shows the student’s results. Temperature in °C 15 20 25 35 45 65 Time taken in seconds 178 156 132 130 122 113
Plot the student’s results on the grid.
Draw a circle around the anomalous result.
Draw a curve of best fit. 180 170 160 150 Time taken in seconds 140 130 120 110 10 20 30 40 50 60 70 Temperature in °C
Give a reason for the anomalous result.
Use your graph to determine the time taken for the mixture to turn blue at 55 °C. Show your working on the graph. time taken = s
Use information from the table to calculate the mean rate of reaction at 20 °C. Use the expression mean rate = time in seconds Give your answer in standard form. mean rate = s–1
Explain how increasing the temperature affects the rate of a reaction. Refer to particle collision theory in your answer.
This question is about organic compounds.
The diagram shows the displayed formula of methanoic acid. O H C O H
Give the total number of atoms in one molecule of methanoic acid.
Determine the relative molecular mass (Mr ) of methanoic acid. Mr =
Explain why methanoic acid is not a hydrocarbon.
The atoms in methanoic acid are held together by covalent bonds.
State, in terms of electrostatic attractions, what is meant by the term covalent bond.
Draw a dot‑and‑cross diagram to show the bonding in a molecule of methanoic acid. Show only the outer electrons of each atom.
No printed figure accompanies this part — in the paper you would draw the diagram (or label the apparatus) in the answer space provided.
Calculate the empirical formula of the organic compound with this composition by mass. C = 52.2% H = 13.0% O = 34.8% empirical formula =
This question is about elements in Group 7 of the Periodic Table.
Which element is a liquid at room temperature?
Choose your answer
astatine
bromine
chlorine
fluorine
What colour is solid iodine?
Choose your answer
black
dark brown
dark grey
purple
Describe a test for chlorine gas.
A sample of chlorine, containing two isotopes, has this percentage composition by mass. chlorine‑35 71.2% chlorine‑37 28.8% Calculate the relative atomic mass of this sample of chlorine. Give your answer to one decimal place. relative atomic mass =
A student is given an aqueous solution of chlorine and an aqueous solution of sodium iodide. Explain how the student can use these solutions to compare the reactivity of chlorine with the reactivity of iodine.
A teacher ignites a piece of magnesium ribbon and places it in a gas jar of oxygen. This is the equation for the reaction. 2Mg + O₂ → 2MgO Give two observations that would be made during this reaction. 1 2
The teacher demonstrates the reaction between aluminium and iron(III) oxide. magnesium fuse mixture of aluminium powder and iron(III) oxide powder The teacher ignites the magnesium fuse. A very exothermic reaction then occurs between aluminium powder and iron(III) oxide. The products of the reaction are iron and aluminium oxide.
State what is meant by the term exothermic.
Give a chemical equation for the reaction between aluminium and iron(III) oxide.
Explain why this reaction is a redox reaction.
A student uses this apparatus to determine the formula of magnesium oxide. crucible lid magnesium ribbon heat This is the student’s method.
Explain why the student lifts the lid.
The mass of magnesium oxide formed is less than expected. Describe what the student should do next to obtain a more accurate value for the mass of magnesium oxide.
This question is about the oxides of some elements in Group 4 of the Periodic Table.
When 5.34 g of lead(II) carbonate are heated, lead(II) oxide and carbon dioxide are formed. This is the equation for the reaction. PbCO₃(s) → PbO(s) + CO₂(g)
Give the name for this type of reaction.
Calculate the maximum mass of lead(II) oxide that can be formed from 5.34 g of lead(II) carbonate. [for PbCO₃, Mr = 267 for PbO, Mr = 223] maximum mass = g
The diagram shows apparatus used to heat lead(II) carbonate. lead(II) carbonate heat
Complete the diagram to show what needs to be added to the apparatus to test that the gas released is carbon dioxide.
Give the result of the test.
Silicon dioxide (SiO₂) and carbon dioxide both contain covalent bonds. Silicon dioxide is a solid with a high melting point. Carbon dioxide is a gas at room temperature. Explain why silicon dioxide has a much higher melting point than carbon dioxide. Refer to structure and bonding in your answer.
A student uses the reaction between zinc powder and dilute nitric acid to prepare some zinc nitrate crystals.
Complete the equation for the reaction by adding the state symbols. Zn ( ) + 2HNO₃ ( ) → Zn(NO₃)₂ ( ) + H₂ ( )
State what the student would observe during this reaction.
In the preparation, the student adds an excess of zinc powder to some dilute nitric acid.
State why the student uses an excess of zinc powder.
Describe what the student should do next to obtain pure, dry crystals of zinc nitrate.
The formula for the zinc nitrate crystals is Zn(NO₃)₂.6H₂O When zinc nitrate crystals are heated, the products are zinc oxide, nitrogen dioxide (NO₂), oxygen and water. Complete the equation for this reaction. 2Zn(NO₃)₂.6H₂O → + + +
A student uses this apparatus to find the heat energy change when ammonium nitrate dissolves in water to form a solution. polystyrene cup distilled water This is the student’s method.
Give two reasons why the student stirs the mixture. 1 2
The diagram shows the minimum temperature of the solution. °C 20 Complete the table by giving the missing information. Give both values to the nearest 0.1 °C. initial temperature of distilled water in °C 23.4 minimum temperature of solution in °C temperature change in °C
The student repeats the experiment, again using 50 cm³ water, and finds that the temperature change is 3.9 °C.
Show that the heat energy change, Q , in this experiment is about 800 J. [c = 4.2 J / g / °C for the solution] [mass = 1.0 g for 1.0 cm³ of solution]
The student uses 2.8 g of ammonium nitrate in this experiment. Calculate the enthalpy change, ΔH, in kJ / mol. Include a sign in your answer. [for NH₄NO₃, Mr = 80] ΔH = kJ / mol
Describe a test to show that the ammonium nitrate solution contains ammonium ions.
In another experiment the student adds anhydrous copper(II) sulfate to distilled water. The table shows the student’s results. initial temperature of water in °C 23.2 maximum temperature of solution in °C 28.5 Explain what the results show about the type of energy change that occurs when anhydrous copper(II) sulfate dissolves in water.
