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The particles of a substance gain energy and change from a regular ordered structure to a disordered structure with large distances between the particles. Which change of state is described?
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In the chromatography experiment shown, which label represents the solvent front?
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X is a mixture of colourless compounds. The diagram shows a chromatogram of X and of three pure compounds, P, Q, and R.
Which statement is not correct?
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Which statements about isotopes of the same element are correct?
1 They are atoms which have the same chemical properties because they have the same number of electrons in their outer shell.
2 They are atoms which have the same number of electrons and neutrons but different numbers of protons.
3 They are atoms which have the same number of electrons and protons but different numbers of neutrons.
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The table shows the electronic structure of four atoms.
[Table_1]
Which two atoms combine to form a covalent compound?
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Which statement describes the attractive forces between molecules (intermolecular forces)?
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Metals consist of a lattice of positive ions in a 'sea of electrons'.
Why is aluminium malleable?
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A sample of 16.0g of a metal oxide, MO, is reduced to 12.8g of the metal, M.
What is the relative atomic mass, $A_r$, of M?
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The equation for the reaction between calcium carbonate and hydrochloric acid is shown.
$$\text{CaCO}_3(s) + 2\text{HCl}(aq) \rightarrow \text{CaCl}_2(aq) + \text{H}_2\text{O}(l) + \text{CO}_2(g)$$
How many moles of calcium carbonate will give 24 \text{cm}^3 of carbon dioxide when reacted with an excess of the acid?
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The diagram shows the electrolysis of molten zinc chloride, $ZnCl_2$.
Which statement is correct?
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The diagram shows some properties that substances may have.
To which labelled part of the diagram does $^{235}U$ belong?
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The diagram shows a simple cell.
For which pair of metals would electrons flow from metal X to metal Y?
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The energy level diagram for the combustion of methane is shown.
Which row gives the equation and energy change for this reaction?
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A liquid X reacts with solid Y to form a gas.
Which two diagrams show suitable methods for investigating the rate (speed) of the reaction?
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Which row describes how the energy of collision between particles changes when concentration and temperature are increased?
[Table_1]
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Methanol is made by reacting carbon monoxide with hydrogen. The reaction is exothermic and is a chemical equilibrium. The equation for the reaction is shown.
$\text{CO(g) + 2H}_2\text{(g)} \rightleftharpoons \text{CH}_3\text{OH(g)}$
Which changes in temperature and pressure increase the yield of methanol?
[Table_1]
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Which equation represents a reduction reaction?
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Which statements are properties of an acid?
1 reacts with ammonium sulfate to form ammonia
2 turns red litmus blue
[Table_1]
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Which row describes whether an amphoteric oxide reacts with acids and bases?
[Table_1]
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Silver chloride is insoluble in water and is prepared by precipitation.
Which two substances can be used to make silver chloride?
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Where in the Periodic Table is the metallic character of the elements greatest?
[Table_1]
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Rubidium is a Group I metal.
Which statement about rubidium is not correct?
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The table gives information about four elements, P, Q, R and S.
[Table_1]
Which elements could be transition elements?
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Part of the Periodic Table is shown.
Which element is a gas that does not form a compound with potassium?
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Some magnesium compounds undergo thermal decomposition.
What are the products of thermal decomposition of magnesium nitrate, $\text{Mg(NO}_3)_2$, and magnesium hydroxide, $\text{Mg(OH)}_2$?
[Table_1]
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Which property is not considered a typical metallic property?
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Iron from a blast furnace is treated with oxygen and with calcium oxide to make steel.
Which substances in the iron are removed?
[Table_1]
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Why is cryolite used during the extraction of aluminium by electrolysis?
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The diagram shows an experiment to investigate how paint affects the rusting of iron.
What happens to the water level in tubes P and Q?
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A new planet has been discovered and its atmosphere has been analysed.
The table shows the composition of its atmosphere.
[Table_1]
Which gases are present in the atmosphere of the planet in a higher percentage than they are in the Earth’s atmosphere?
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The gases coming from a car’s engine contain oxides of nitrogen.
How are these oxides formed?
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Ammonia is manufactured by a reversible reaction.
$$\text{N}_2(g) + 3\text{H}_2(g) \rightleftharpoons 2\text{NH}_3(g)$$
The forward reaction is exothermic. What is the effect of increasing the pressure on the percentage yield and rate of formation of ammonia?
| percentage yield | rate of formation |
|:----------------:|:------------------:|
| decreases | decreases |
| decreases | increases |
| increases | decreases |
| increases | increases |
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The Contact process is used for the manufacture of sulfuric acid. Which statement about this process is not correct?
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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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The diagram shows the separation of petroleum into fractions.
What could X, Y and Z represent?
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Which compound is \textit{not} an alkane, $C_nH_{2n+2}$?
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An ester is formed when a carboxylic acid reacts with an alcohol. Which ester is formed when propanoic acid and ethanol react?
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What is an advantage of producing ethanol by fermentation of sugar compared to the catalytic addition of steam to ethene?
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In which row are the monomer and polymer chain correctly matched? [Table_1]
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Which two polymers have the same linkages bonding the monomers together?
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