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Decane has a freezing point of $-30^{\circ}C$ and a boiling point of $174^{\circ}C$.
A small sample of decane is placed in an open beaker in an oven at a temperature of $120^{\circ}C$ and at atmospheric pressure for 24 hours.
What happens to the sample of decane?
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A student put exactly 25.00 cm$^3$ of dilute hydrochloric acid into a conical flask.
The student added 2.5 g of solid sodium carbonate and measured the change in temperature of the mixture.
Which apparatus does the student need to use?
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A student separates sugar from pieces of broken glass by dissolving the sugar in water and filtering off the broken glass.
What is the filtrate?
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Which statement explains why metals conduct electricity when solid?
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The equation for the reaction of iron(III) oxide with carbon monoxide is shown.
$$\text{Fe}_2\text{O}_3(s) + 3\text{CO}(g) \rightarrow 2\text{Fe}(s) + 3\text{CO}_2(g)$$
What is the maximum mass of iron that can be made from 480 g of iron(III) oxide?
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Which statement describes the attractive forces between molecules?
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The formula of an aluminium ion is $Al^{3+}$.
What is the formula of aluminium sulfate?
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Which statements about the products of electrolysis, using inert electrodes, are correct?
1. When molten lead(II) bromide is electrolysed, bromine is formed at the cathode.
2. When dilute sulfuric acid is electrolysed, oxygen is formed at the anode.
3. When concentrated aqueous sodium chloride is electrolysed, sodium is formed at the cathode.
4. When concentrated hydrochloric acid is electrolysed, chlorine is formed at the anode.
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Chlorine reacts with ethane to produce chloroethane and hydrogen chloride.
The reaction is exothermic.
The bond energies are shown in the table.
[Table_1]
What is the energy change for the reaction?
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Hydrogen is used as a fuel in rockets and is also used in hydrogen fuel cells.
Which statements are correct?
1 Both uses produce water vapour.
2 Burning hydrogen produces polluting gases.
3 A fuel cell produces electricity.
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Which statements about the effect of increasing the temperature on the rate of a reaction are correct?
1. It increases the rate of a reaction.
2. It increases the activation energy.
3. It increases the frequency of collisions.
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Ammonia is made by reacting nitrogen with hydrogen. The equation for the reaction is shown.
$\text{N}_2(g) + 3\text{H}_2(g) \rightleftharpoons 2\text{NH}_3(g)$
The forward reaction is exothermic. Which changes in temperature and pressure decrease the yield of ammonia?
[Table_1]
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X is a pink solid.
Y is a blue solid.
When X is heated, water is produced and the solid turns blue.
When water is added to Y, the solid turns pink.
What are X and Y?
[Table_1]
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Iron(II) chloride solution reacts with chlorine gas.
The equation is shown.
$$2FeCl_2(aq) + Cl_2(g) \rightarrow 2FeCl_3(aq)$$
Which statements about this reaction are correct?
1. $Fe^{2+}$ ions are reduced to $Fe^{3+}$ ions.
2. Chlorine acts as a reducing agent.
3. $Fe^{2+}$ ions each lose an electron.
4. $Cl_2$ molecules are reduced to $Cl^-$ ions.
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Which row describes the properties of an acid?
[Table_1]
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Copper(II) chloride crystals are made by adding solid copper(II) carbonate to dilute hydrochloric acid until no more dissolves. Which process is used to obtain pure copper(II) chloride crystals from the mixture?
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Moving from right to left across the Periodic Table the elements show increasing metallic character.
Why does metallic character increase from right to left across a period?
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A period of the Periodic Table is shown.
[Table_1]
The letters are not their chemical symbols.
Which statement is correct?
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Group VII elements show trends in their physical properties going down the group.
[Table_1]
Which row shows the missing headings for the properties in the table?
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Some properties of two metals, G and H, are shown.
[Table_1: Showing properties of metal G and metal H]
Which row about metals G and H is correct?
[Table_2: Options for metal G and metal H]
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The noble gases are in Group VIII of the Periodic Table.
Which statement explains why noble gases are unreactive?
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Which statement is correct for all metals?
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Which statement about the extraction of metals is correct?
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Aluminium objects do not need protection from corrosion.
Iron objects must be protected from corrosion.
Which statement explains why aluminium resists corrosion?
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Which statements about the thermal decomposition of copper(II) nitrate are correct?
1. A brown gas is given off.
2. A gas which relights a glowing splint is given off.
3. The solid residue is an acidic oxide.
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Covering iron with zinc prevents the iron from rusting even when the zinc is scratched.
Covering iron with tin prevents the iron from rusting, but when the tin is scratched the iron underneath starts to rust.
Which statement is correct?
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Which statements about the Haber process are correct?
1. One of the raw materials is extracted from liquid air by fractional distillation.
2. One of the raw materials is produced by the reaction of steam and methane.
3. The catalyst for the Haber process is vanadium(V) oxide.
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Which raw material is used in the Contact process?
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Lime (calcium oxide) is used to treat waste water from a factory.
Which substance is removed by the lime?
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An alkane molecule of molecular formula $C_8H_{18}$ undergoes cracking. The equation for the reaction is shown.
$C_8H_{18} \rightarrow Q + 2R$
Substance R has two carbon atoms per molecule and decolourises aqueous bromine.
What is substance Q?
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Fuel X produces carbon dioxide and water when it is burned in air. So does fuel Y. What could X and Y be? [Table_1]
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Which molecule contains only single covalent bonds?
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Alkanes react with chlorine to form chloroalkanes.
Which statement about the reactions of alkanes with chlorine is correct?
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Part of the structure of a very large molecule is shown. Which term describes the small unit used to make this molecule?
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Propene reacts with steam to form propanol.
$\text{C}_3\text{H}_6(g) + \text{H}_2\text{O}(g) \to \text{C}_3\text{H}_7\text{OH}(g)$
Which type of reaction takes place?
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Which statement about aqueous ethanoic acid is correct?
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The diagram shows the partial structure of Terylene.
From which pair of compounds is it made?
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