A Level Chemistry 9701 Paper 11, May/June 2024

Sample X is added to water and made up to a total volume of $200{\text{ cm}}^3$. This gives a solution of $0.100{\text{ mol dm}}^{-3}\text{ HCl}$. What is X? A $10{\text{ cm}}^3$ of $1.00{\text{ mol dm}}^{-3}\text{ HCl}$ B $30{\text{ cm}}^3$ of $0.90{\text{ mol dm}}^{-3}\text{ HCl}$ C $50{\text{ cm}}^3$ of $0.40{\text{ mol dm}}^{-3}\text{ HCl}$ D $100{\text{ cm}}^3$ of $0.30{\text{ mol dm}}^{-3}\text{ HCl}$

A mixture of $10{\text{ cm}}^3$ of methane and $10{\text{ cm}}^3$ of ethane was sparked with an excess of oxygen. After cooling, the residual gas was passed through aqueous potassium hydroxide. All gas volumes were measured at the same temperature and pressure. Which volume of gas was absorbed by the alkali? A $15{\text{ cm}}^3$ B $20{\text{ cm}}^3$ C $30{\text{ cm}}^3$ D $40{\text{ cm}}^3$

Z is a compound of two elements, X and Y. Element X shows a very large increase between its 5th and 6th ionisation energies. It has the second largest 1st ionisation energy in its group. Element Y shows a very large increase between its 6th and 7th ionisation energies. It has the largest 1st ionisation energy in its group. What is compound Z? A ${\text{NO}}_2$ B ${\text{PCl}}_5$ C ${\text{P}}_4{\text{O}}_{10}$ D ${\text{SF}}_6$

Which statement about ${}_{53}^{131}\text{I}$ is correct? A A negative ion of ${}_{53}^{131}\text{I}$ contains 53 neutrons and 52 electrons. B A negative ion of ${}_{53}^{131}\text{I}$ contains 53 neutrons and 54 electrons. C A negative ion of ${}_{53}^{131}\text{I}$ contains 78 neutrons and 52 electrons. D A negative ion of ${}_{53}^{131}\text{I}$ contains 78 neutrons and 54 electrons.

When solid aluminium chloride is heated, ${\text{Al}}_2{\text{Cl}}_6$ is formed. Which bonding is present in ${\text{Al}}_2{\text{Cl}}_6$? A covalent and coordinate (dative covalent) B covalent only C ionic and coordinate (dative covalent) D ionic only

The structure of the sulfur dioxide molecule is shown. $$\ddot{\text{O}}=\ddot{\text{S}}=\ddot{\text{O}}$$ What is the shape of the sulfur dioxide molecule? A linear B non-linear C pyramidal D tetrahedral

What is the density of a sample of fluorine gas at $32{}^{\circ }\text{C}$ and $100000\text{ Pa}$? Assume fluorine behaves as an ideal gas under these conditions. A $1.4{\text{ g dm}}^{-3}$ B $1.5{\text{ g dm}}^{-3}$ C $1.6{\text{ g dm}}^{-3}$ D $1.7{\text{ g dm}}^{-3}$

The graph shows the boiling points of the hydrogen compounds of Group 16 elements. Which statement correctly explains why water does not fit the trend of the other compounds? A There are fewer electrons in the oxygen atoms so there is less shielding of the nuclear charge. B There are strong hydrogen bonds in water but not in the other compounds. C The covalent bonds in water are much stronger than in the other compounds. D The water molecules are smaller and so have stronger van der Waals' forces.

An energy cycle is shown. The energy changes involved are X, Y and Z. The numerical value of energy change Y is either $-890$ or $+890$. The numerical value of energy change Z is either $-964$ or $+964$. Which of the three values are negative? A X and Z B X only C Y and Z D Y only

For a certain endothermic reaction, the activation energy is numerically equal to twice the enthalpy change of reaction. Which reaction pathway diagram is correct for this reaction?

Sodium chromate(VI), ${\text{Na}}_2{\text{CrO}}_4$, is manufactured by heating chromite, ${\text{FeCr}}_2{\text{O}}_4$, with sodium carbonate in an oxidising atmosphere. Chromite contains ${\text{Cr}}_2{\text{O}}_4^{2-}$ ions. $$2{\text{FeCr}}_2{\text{O}}_4+4{\text{Na}}_2{\text{CO}}_3+3\frac{1}{2}{\text{O}}_2\to 4{\text{Na}}_2{\text{CrO}}_4+{\text{Fe}}_2{\text{O}}_3+4{\text{CO}}_2$$ What happens in this reaction? A Chromium and iron are the only elements oxidised. B Chromium, iron and carbon are oxidised. C Only chromium is oxidised. D Only iron is oxidised.

Oxygen can be prepared by the reaction of potassium manganate(VII), ${\text{KMnO}}_4$, hydrogen peroxide, ${\text{H}}_2{\text{O}}_2$, and sulfuric acid, ${\text{H}}_2{\text{SO}}_4$. Each ${\text{H}}_2{\text{O}}_2$ molecule loses two electrons in this reaction. The other products of the reaction are potassium sulfate, manganese(II) sulfate and water. How many moles of oxygen gas are produced when $1.0\text{ mol}$ of ${\text{KMnO}}_4$ reacts with an excess of ${\text{H}}_2{\text{O}}_2$ in acidic conditions? A $2.0\text{ mol}$ B $2.5\text{ mol}$ C $4.5\text{ mol}$ D $5.0\text{ mol}$

An alcohol, $\text{ROH}$, reacts reversibly with ethanoic acid to produce an ester. $$\text{ROH(l)}+{\text{CH}}_3\text{COOH(l)}\rightleftharpoons {\text{CH}}_3\text{COOR(l)}+{\text{H}}_2\text{O(l)}$$ $3.0\text{ mol}$ of $\text{ROH}$, $2.0\text{ mol}$ of ethanoic acid and $1.0\text{ mol}$ of water are mixed together. At equilibrium, $1.5\text{ mol}$ of ${\text{CH}}_3\text{COOR}$ is present. What is the value of the equilibrium constant, $K_c$, for this reaction? A $0.20$ B $0.25$ C $2.00$ D $5.00$

Graphs can be drawn to show the percentage of ammonia at equilibrium when nitrogen and hydrogen are mixed at different temperatures and pressures. Which diagram correctly represents these two graphs?

The Boltzmann distribution for the hydrogenation of an alkene at a particular temperature in the absence of a catalyst is shown. Which row correctly describes the effects of adding a nickel catalyst to the reaction vessel?

Elements Y and Z are both in Period 3 of the Periodic Table. When the chloride of element Y is added to water, it reacts and a solution of $\text{pH }2$ is produced. When the chloride of element Z is added to water, it dissolves and a solution of $\text{pH }7$ is produced. Which statement explains these observations? A Both chlorides hydrolyse in water. B Element Y is magnesium and element Z is sodium. C Element Y is phosphorus and element Z is aluminium. D Element Y is silicon and element Z is sodium.

Aluminium, silicon and phosphorus are elements in Period 3 of the Periodic Table. Each element forms an oxide. Which row is correct?

Which statement is correct? A The atomic radius of silicon is larger than that of aluminium. B The boiling point of chlorine is higher than that of silicon. C The first ionisation energy of sulfur is greater than that of phosphorus. D The electrical conductivity of magnesium is greater than that of sodium.

All solubility data in this question is given at the same temperature. The table gives some data for compounds of calcium and for compounds of X, an unidentified element in Group 2.

What is the missing data for element X?

What is the total volume of gas produced, measured at room conditions, when $0.010\text{ mol}$ of anhydrous magnesium nitrate is completely decomposed by heating? A $240{\text{ cm}}^3$ B $480{\text{ cm}}^3$ C $600{\text{ cm}}^3$ D $720{\text{ cm}}^3$

A solid sodium halide, $\text{NaX}$, is reacted with concentrated sulfuric acid. The lowest oxidation state of sulfur in the products is $+4$. Halogen ${\text{Y}}_2$ is less volatile than halogen ${\text{X}}_2$. What are the identities of sodium halide $\text{NaX}$ and halogen ${\text{Y}}_2$?

Compound Q dissolves in water. $\text{Q(aq)}$ does not react with dilute sulfuric acid. $\text{Q(aq)}$ forms a precipitate when aqueous silver nitrate is added. This precipitate is partially soluble in aqueous ammonia. What could be compound Q? A barium bromide B barium iodide C magnesium bromide D magnesium iodide

Nitrogen dioxide is a gas that contributes to air pollution. It is produced in internal combustion engines. Which statement is correct? A Nitrogen dioxide acts as a catalyst in the atmospheric oxidation of sulfur dioxide to sulfur trioxide. B Nitrogen dioxide reacts to form nitrogen monoxide in the catalytic converter of a car exhaust system. C PAN forms when nitrogen dioxide reacts with the gases formed by complete combustion of the fuel. D Under high pressure in an internal combustion engine, nitrogen dioxide forms from impurities in the fuel.

What is the bond angle in the ammonium ion? A ${90}^{\circ }$ B ${107}^{\circ }$ C ${109.5}^{\circ }$ D ${120}^{\circ }$

Structural isomerism and stereoisomerism should be taken into account when answering this question. The structure of 3-methylcyclobutene is shown. A mixture containing all stereoisomers of 3-methylcyclobutene is treated with $\text{HBr}$. This produces a mixture of isomeric bromomethylcyclobutanes. How many stereoisomers does 3-methylcyclobutene have, and how many isomeric bromomethylcyclobutanes are present in the product mixture?

The diagram shows the structure of X. Which row is correct?

The diagram shows the skeletal formula of citric acid. What is the molecular formula of citric acid? A ${\text{C}}_6{\text{H}}_8{\text{O}}_7$ B ${\text{C}}_6{\text{H}}_4{\text{O}}_7$ C ${\text{C}}_8{\text{H}}_8{\text{O}}_7$ D ${\text{C}}_{10}{\text{H}}_8{\text{O}}_7$

Which reaction occurs when ethane and chlorine are mixed in diffused sunlight? A a free-radical substitution with hydrogen given off B a free-radical substitution with hydrogen chloride given off C a free-radical substitution with no gas given off D a nucleophilic substitution with hydrogen chloride given off

A molecule of geraniol is shown. What is formed when geraniol is reacted with an excess of cold dilute acidified ${\text{MnO}}_4^{-}$?

Q is either a primary or a tertiary halogenoalkane. Q undergoes hydrolysis with aqueous sodium hydroxide. The first step in the mechanism of this reaction involves two species reacting together. Which row is correct?

2-bromopropane is converted to 1,2-dibromopropane in a pathway involving two reactions. $$\text{2-bromopropane}\stackrel{\text{reaction 1}}{\to }\text{compound X}\stackrel{\text{reaction 2}}{\to }\text{1,2-dibromopropane}$$ What are the reagents and conditions for the two reactions?

Compound X is a single, pure, optical isomer. Compound X is heated with an excess of concentrated ${\text{H}}_2{\text{SO}}_4$. Only one organic product is formed. What is compound X?

Which reagents could be used to form 2-bromobutane from butan-1-ol? A bromine and ultraviolet light B concentrated sulfuric acid with potassium bromide, under reflux C concentrated sulfuric acid followed by bromine D concentrated sulfuric acid followed by hydrogen bromide

X is a non-cyclic ketone with a single carbonyl group and no other functional groups. Ketone X has the following properties. ● When ketone X is treated with ${\text{NaBH}}_4$, the organic product has a $M_r$ $2.3256\mathrm{\%}$ greater than the $M_r$ of ketone X. ● Ketone X gives a yellow precipitate with alkaline ${\text{I}}_2\text{(aq)}$. How many isomeric ketones could be ketone X? A 1 B 2 C 3 D 4

Compound Y: ● changes the colour of acidified ${\text{K}}_2{\text{Cr}}_2{\text{O}}_7$ from orange to green ● has no effect on Fehling's reagent ● produces an orange precipitate with 2,4-dinitrophenylhydrazine reagent. What is compound Y?

The product of the reaction between propanone and hydrogen cyanide is hydrolysed under acidic conditions. What is the formula of the final product? A ${\text{CH}}_3\text{CH(OH)COOH}$ B ${\text{CH}}_3{\text{CH}}_2{\text{CH}}_2\text{COOH}$ C $({\text{CH}}_3{)}_2{\text{CHCONH}}_2$ D $({\text{CH}}_3{)}_2\text{C(OH)COOH}$

P is a carboxylic acid with molecular formula ${\text{C}}_5{\text{H}}_{10}{\text{O}}_2$. Carboxylic acid P reacts with an excess of ${\text{LiAlH}}_4$ to form compound Q. Which pairs of molecules could be carboxylic acid P and compound Q?

A 1 and 2 B 1 and 3 C 2 and 3 D 3 only

Compound X is treated with an excess of dilute aqueous potassium hydroxide. What is the structure of the organic product?

A section showing two repeat units of an addition polymer is shown. What is the identity of the monomer that produced this polymer? A 2-chloro-3-methylbutane B 2-chloro-3-methylbut-2-ene C 2-chloropent-2-ene D 2,4-dichloro-3,3,4,5-tetramethylhexane

The relative atomic mass of antimony is $121.76$. Antimony has two isotopes. The mass numbers of the two isotopes differ by two. The isotope with the lower mass number is the more abundant. What is the percentage abundance of the isotope with the higher mass number? A $12\mathrm{\%}$ B $38\mathrm{\%}$ C $62\mathrm{\%}$ D $88\mathrm{\%}$