A Level Chemistry 9701 Paper 13, May/June 2023

Propanoic acid is treated with reagent X at room temperature. The organic product of the reaction is sodium propanoate. No gas is produced during the reaction. What could be reagent X? A $\mathrm{N}\mathrm{a}\mathrm{H}\mathrm{C}{\mathrm{O}}_3(\mathrm{a}\mathrm{q})$ B $\mathrm{N}\mathrm{a}\mathrm{O}\mathrm{H}(\mathrm{a}\mathrm{q})$ C $\mathrm{N}{\mathrm{a}}_2\mathrm{C}{\mathrm{O}}_3(\mathrm{a}\mathrm{q})$ D $\mathrm{N}{\mathrm{a}}_2\mathrm{S}{\mathrm{O}}_4(\mathrm{a}\mathrm{q})$

The ionic equation shows iodide ions reacting with manganate(VII) ions in acidic solution. $$u\mathrm{M}\mathrm{n}{\mathrm{O}}_4^{-}+v{\mathrm{H}}^{+}+w{\mathrm{I}}^{-}\to x\mathrm{M}{\mathrm{n}}^{2+}+y{\mathrm{H}}_2\mathrm{O}+z{\mathrm{I}}_2$$ The letters $u$, $v$, $w$, $x$, $y$ and $z$ all represent whole numbers. Two or more of $u$, $v$, $w$, $x$, $y$ and $z$ are the same as each other. What is the lowest possible value of $v$? A 2 B 8 C 10 D 16

A piece of rock has a mass of $2.00\text{ g}$. It contains calcium carbonate, but no other basic substances. It neutralises exactly $36.0{\text{ cm}}^3$ of $0.500{\text{ mol dm}}^{-3}$ hydrochloric acid. What is the percentage by mass of calcium carbonate in the $2.00\text{ g}$ piece of rock? A 22.5% B 45.0% C 72.0% D 90.1%

L and M are elements in Period 3 of the Periodic Table. Neither element is argon. Information about the Pauling electronegativity values of L and M is given.

Three statements about elements L and M are given. 1 Element L contains covalent bonds. 2 Element L has a higher atomic number than element M. 3 A compound of L and M contains ionic bonds. Which statements are correct? A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 and 3 only

Ammonia reacts with acids to form the ammonium ion. $$\mathrm{N}{\mathrm{H}}_3+{\mathrm{H}}^{+}\rightleftharpoons \mathrm{N}{\mathrm{H}}_4^{+}$$ Which row is correct?

Electronegativity differences can be used to help determine the oxidation number of an atom in different species. A number of rules are used which include: • The more electronegative atom is given a negative oxidation number. • Hydrogen is more electronegative than Group 1 metals. • Oxygen is more electronegative than hydrogen. Which row is correct?

Which assumptions are made about ideal gases? 1 Ideal gases contain molecules with no mass. 2 Ideal gases contain molecules with no volume. 3 Ideal gases have no intermolecular forces. A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 and 3 only

A $200{\text{ cm}}^3$ sample of water has an amount of oxygen gas dissolved in it. This amount of oxygen gas has a volume of $6.00{\text{ cm}}^3$ when measured at $1.00\times {10}^5\text{ Pa}$ and $35{}^{\circ }\mathrm{C}$. What is the concentration of oxygen gas in the water? (You should assume that oxygen behaves as an ideal gas.) A $2.34\times {10}^{-4}{\text{ mol dm}}^{-3}$ B $1.17\times {10}^{-3}{\text{ mol dm}}^{-3}$ C $1.25\times {10}^{-3}{\text{ mol dm}}^{-3}$ D $1.03\times {10}^{-2}{\text{ mol dm}}^{-2}$

Which statement explains why buckminsterfullerene has a lower melting point than graphite? A Buckminsterfullerene exists as discrete molecules with weak intermolecular bonding. B Graphite is partly ionic as its structure contains mobile electrons and it conducts electricity. C The carbon–carbon bonds in buckminsterfullerene are shorter and more strained. D The mobile electrons in graphite mean it has a metallic structure.

Which equation represents the reaction whose standard enthalpy change is the standard enthalpy change of formation of water? A $2{\mathrm{H}}_2(\mathrm{g})+{\mathrm{O}}_2(\mathrm{g})\to 2{\mathrm{H}}_2\mathrm{O}(\mathrm{l})$ B ${\mathrm{H}}_2(\mathrm{g})+\frac{1}{2}{\mathrm{O}}_2(\mathrm{g})\to {\mathrm{H}}_2\mathrm{O}(\mathrm{l})$ C ${\mathrm{H}}^{+}(\mathrm{a}\mathrm{q})+\mathrm{O}{\mathrm{H}}^{-}(\mathrm{a}\mathrm{q})\to {\mathrm{H}}_2\mathrm{O}(\mathrm{l})$ D $2\mathrm{H}(\mathrm{g})+\mathrm{O}(\mathrm{g})\to {\mathrm{H}}_2\mathrm{O}(\mathrm{l})$

Which mixture will react to form exactly one mole of water?

The enthalpy change for neutralisation of $\mathrm{H}\mathrm{N}{\mathrm{O}}_3(\mathrm{a}\mathrm{q})$ with $\mathrm{N}\mathrm{a}\mathrm{O}\mathrm{H}(\mathrm{a}\mathrm{q})$ is $-57.0{\text{ kJ mol}}^{-1}$. In an experiment, $20.0{\text{ cm}}^3$ of $4.00{\text{ mol dm}}^{-3}$ $\mathrm{H}\mathrm{N}{\mathrm{O}}_3$ is mixed with $30.0{\text{ cm}}^3$ of $2.00{\text{ mol dm}}^{-3}$ $\mathrm{N}\mathrm{a}\mathrm{O}\mathrm{H}$ in an insulated container. The initial temperature of both solutions is $25.0{}^{\circ }\mathrm{C}$. It can be assumed that the heat capacity of the product mixture is $4.2{\text{ J cm}}^{-3}{}^{\circ }{\mathrm{C}}^{-1}$ and that there are no heat losses. What is the maximum final temperature of the mixture? A $41.3{}^{\circ }\mathrm{C}$ B $44.0{}^{\circ }\mathrm{C}$ C $46.7{}^{\circ }\mathrm{C}$ D $52.1{}^{\circ }\mathrm{C}$

Some bond energies are listed.

One mole of hydrogen reacts with oxygen to give water vapour. Using the bond energy data, what is the value for the enthalpy change of this reaction? A $+221{\text{ kJ mol}}^{-1}$ B $+6{\text{ kJ mol}}^{-1}$ C $-242{\text{ kJ mol}}^{-1}$ D $-417{\text{ kJ mol}}^{-1}$

Which particle contains nitrogen in the same oxidation state as in the ion ${\mathrm{N}}_2{\mathrm{O}}_2^{2-}$? A $\mathrm{N}{\mathrm{H}}_2\mathrm{F}$ B ${\mathrm{N}}_2{\mathrm{O}}_4$ C $\mathrm{N}{\mathrm{O}}_3^{-}$ D $\mathrm{H}\mathrm{N}{\mathrm{F}}_2$

Sulfur dioxide reacts with oxygen as shown. $$2\mathrm{S}{\mathrm{O}}_2(\mathrm{g})+{\mathrm{O}}_2(\mathrm{g})\rightleftharpoons 2\mathrm{S}{\mathrm{O}}_3(\mathrm{g})\mathrm{\Delta }{H}^{\ominus }=-197{\text{ kJ mol}}^{-1}$$ Which change will move the equilibrium position to the right side and change the value of the equilibrium constant, $K_c$? A the addition of a catalyst B increasing the pressure of the reaction C decreasing the temperature of the reaction D decreasing the concentration of product

Solutions X and Y both have a concentration of $0.10{\text{ mol dm}}^{-3}$. A fixed volume of solution X is added to a conical flask, and solution Y is added from a burette to the conical flask. A titration is performed. The diagram shows the pH titration curve for the acid–base reaction between the solutions. What are solutions X and Y?

Which row shows the expected properties of the element astatine when compared to the properties of the element iodine?

The rate of an exothermic reaction is followed by measuring the concentration of a reactant at regular time intervals. During the experiment the temperature of the reaction mixture is not controlled. Which graph shows the change in concentration of reactant against time? A [Graph showing a straight line decreasing with a constant negative slope from initial concentration to 0] B [Graph showing concentration initially decreasing slowly, then decreasing more rapidly, then plateauing asymptotically towards 0] C [Graph showing a typical exponential decay curve with decreasing rate over time] D [Graph showing concentration increasing over time in an S-curve]

For a particular reversible reaction the backward reaction is endothermic. The activation energy of the backward reaction is $160{\text{ kJ mol}}^{-1}$. It can be assumed that the backward reaction proceeds by a mechanism that is the exact reverse of the mechanism for the forward reaction. Which statement about the activation energy of the forward reaction is correct? A The activation energy of the forward reaction is equal to $-160{\text{ kJ mol}}^{-1}$. B The activation energy of the forward reaction is $0{\text{ kJ mol}}^{-1}$ but less than $+160{\text{ kJ mol}}^{-1}$. C The activation energy of the forward reaction is equal to $+160{\text{ kJ mol}}^{-1}$. D The activation energy of the forward reaction is greater than $+160{\text{ kJ mol}}^{-1}$.

$\mathrm{H}\mathrm{C}\mathrm{N}$ has been detected in interstellar gas. The molecules below have also been detected in interstellar gas. Which molecule contains the same total number of valence shell (outer shell) electrons as $\mathrm{H}\mathrm{C}\mathrm{N}$? A $\mathrm{H}\mathrm{N}\mathrm{O}$ B $\mathrm{N}{\mathrm{H}}_3$ C $\mathrm{N}\mathrm{O}$ D $\mathrm{P}\mathrm{N}$

The diagram shows the Boltzmann distribution of the energy of gaseous molecules at a particular temperature. Which statement is correct? A If the temperature of the gas is raised, the height of the maximum of the curve increases. B If the temperature of the gas is raised, the maximum of the curve moves to the right. C The length of the line labelled X shows the activation energy for the reaction. D The length of the line labelled Y shows the enthalpy change of the reaction.

The elements magnesium and phosphorus are reacted separately with an excess of oxygen to form their oxides. Each oxide is then added separately to water and the pH values of the resulting solutions are measured. The same two elements are reacted separately with an excess of chlorine to form their chlorides. Each chloride is then added separately to water and the pH values of the resulting solutions are measured. Which row is correct?

Equal volumes of saturated solutions of magnesium hydroxide, calcium hydroxide and strontium hydroxide are completely neutralised with dilute sulfuric acid. The water is gently evaporated from each of the resulting solutions, leaving the corresponding solid sulfates. These solid sulfates are completely dissolved in the minimum volume of water needed to produce saturated solutions. Which statement about the volumes of water needed to dissolve the sulfates is correct? A The calcium sulfate will require the greatest volume of water. B The magnesium sulfate will require the greatest volume of water. C The strontium sulfate will require the greatest volume of water. D They will all require the same volume of water.

Which statement about the halogens is correct? A Iodine cannot behave as an oxidising agent. B The volatility of the elements increases from chlorine to iodine because of the increase in molecular size down the group. C When an equimolar mixture of chlorine and hydrogen is exploded, only one product is formed. D When concentrated sulfuric acid is added to solid sodium bromide, hydrogen sulfide is one of the products.

When concentrated sulfuric acid is added to solid sodium bromide, bromine gas is produced, along with a number of other products. However, when concentrated sulfuric acid is added to solid sodium chloride, only hydrogen chloride and sodium hydrogensulfate are produced. What is the reason for this difference? A Bromine is less volatile than chlorine. B Hydrochloric acid is a weak acid. C Sulfuric acid is not an oxidising agent. D The bromide ion is a stronger reducing agent than the chloride ion.

Which statement about the oxides of nitrogen is correct? A During lightning storms, atmospheric oxygen and nitrogen combine to form oxides of nitrogen. B In a catalytic converter, nitrogen monoxide is removed by reaction with carbon dioxide. C In car engines, the restricted supply of oxygen eliminates the possibility of the formation of oxides of nitrogen. D In the atmosphere, nitrogen monoxide reacts with sulfur dioxide to produce sulfur trioxide.

Structural isomerism and stereoisomerism should be considered when answering this question. 2-bromopentane is heated with an excess of ethanolic sodium hydroxide. How many different hydrocarbons are produced? A 1 B 2 C 3 D 4

Which compound is a secondary alcohol that can be dehydrated to form an alkene with $M_r=70$? A $\mathrm{C}{\mathrm{H}}_3\mathrm{C}\mathrm{H}(\mathrm{C}{\mathrm{H}}_3)\mathrm{C}(\mathrm{C}{\mathrm{H}}_3)(\mathrm{O}\mathrm{H})\mathrm{C}{\mathrm{H}}_3$ B $\mathrm{C}{\mathrm{H}}_3\mathrm{C}\mathrm{H}(\mathrm{C}{\mathrm{H}}_3)\mathrm{C}\mathrm{H}(\mathrm{O}\mathrm{H})\mathrm{C}{\mathrm{H}}_3$ C $\mathrm{C}{\mathrm{H}}_3\mathrm{C}{\mathrm{H}}_2\mathrm{C}{\mathrm{H}}_2\mathrm{C}\mathrm{H}(\mathrm{O}\mathrm{H})\mathrm{C}{\mathrm{H}}_3$ D $\text{cyclopentanol}$

The conversion of propan-1-ol into propan-2-ol can be completed in a two-stage synthesis. The first stage is to heat the propan-1-ol with concentrated sulfuric acid. Which reagent would be needed to complete the second stage? A cold dilute acidified manganate(VII) ions B hot concentrated acidified manganate(VII) ions C steam with phosphoric acid D aqueous sodium hydroxide

Which type of reaction happens during the hydrolysis of 2-bromopropane? A electrophilic addition B free radical substitution C nucleophilic addition D nucleophilic substitution

A mixture of ethane and an excess of chlorine is exposed to UV light. How many different products, each containing only two carbon atoms and at least one chlorine atom per molecule, can be formed? A 8 B 9 C 10 D 12

When 1-methylcyclohexene reacts with $\mathrm{B}{\mathrm{r}}_2$ the product is X. When 1-methylcyclohexene reacts with $\mathrm{H}\mathrm{B}\mathrm{r}$ the major product is Y. $$\mathrm{X}\stackrel{\mathrm{B}{\mathrm{r}}_2}{\leftarrow }\text{1-methylcyclohexene}\stackrel{\mathrm{H}\mathrm{B}\mathrm{r}}{\to }\mathrm{Y}$$ Which statement is correct? A X is a mixture of two stereoisomers; Y does not have stereoisomers. B X is a mixture of two stereoisomers; Y is a mixture of four stereoisomers. C X is a mixture of four stereoisomers; Y does not have stereoisomers. D X is a mixture of four stereoisomers; Y is a mixture of four stereoisomers.

T is an organic compound which contains 66.7% by mass of carbon. T also contains one atom of oxygen per molecule. T reacts with alkaline ${\mathrm{I}}_2(\mathrm{a}\mathrm{q})$ to produce a yellow precipitate. What is T? A methylpropan-2-ol B butan-2-ol C butanal D butanone

Which statement about butanone is correct? A Butanone can be dehydrated by concentrated sulfuric acid to give $\mathrm{C}{\mathrm{H}}_2=\mathrm{C}\mathrm{H}\mathrm{C}\mathrm{H}=\mathrm{C}{\mathrm{H}}_2$. B Butanone gives a positive result with Tollens’ reagent. C Butanone reacts with $\mathrm{H}\mathrm{C}\mathrm{N}$ by an electrophilic addition mechanism. D Butanone reacts with $\mathrm{N}\mathrm{a}\mathrm{B}{\mathrm{H}}_4$ to give a chiral product.

Methylbut-2-ene reacts with $\mathrm{H}\mathrm{B}\mathrm{r}$ at room temperature to produce compound X as a major product. Compound X reacts with $\mathrm{K}\mathrm{C}\mathrm{N}$ in ethanol to produce compound Y. Compound Y is hydrolysed with acid to produce compound Z. What is compound Z? A 2,2-dimethylbutanoic acid B 2,3-dimethylbutanoic acid C 2-methylpentanoic acid D 3-methylpentanoic acid

Compound Q can be hydrolysed by $\mathrm{H}\mathrm{C}\mathrm{l}(\mathrm{a}\mathrm{q})$. The two products of this hydrolysis have the same empirical formula. What could Q be? A $\mathrm{C}{\mathrm{H}}_3\mathrm{C}{\mathrm{O}}_2\mathrm{C}{\mathrm{H}}_2\mathrm{C}{\mathrm{H}}_2\mathrm{O}\mathrm{H}$ B $\mathrm{C}{\mathrm{H}}_3\mathrm{C}{\mathrm{O}}_2\mathrm{C}{\mathrm{H}}_2\mathrm{C}{\mathrm{H}}_2\mathrm{C}{\mathrm{O}}_2\mathrm{H}$ C $\mathrm{C}{\mathrm{H}}_3\mathrm{C}{\mathrm{H}}_2\mathrm{C}{\mathrm{O}}_2\mathrm{C}{\mathrm{H}}_2\mathrm{C}{\mathrm{H}}_2\mathrm{C}{\mathrm{H}}_3$ D $\mathrm{C}{\mathrm{H}}_3\mathrm{C}{\mathrm{H}}_2\mathrm{C}\mathrm{H}(\mathrm{O}\mathrm{H})\mathrm{C}\mathrm{H}(\mathrm{O}\mathrm{H})\mathrm{C}{\mathrm{H}}_2\mathrm{C}{\mathrm{H}}_3$

An unsaturated carboxylic acid reacts with alcohol X to form an ester. The structure of the ester is shown. Which geometrical isomer is shown in this ester and to which class of alcohol does X belong?

Which two-step process converts cyclohexanol into cyclohexane-1,2-diol?

In polymer G every carbon atom in the polymer chain is bonded to one hydrogen atom and one methyl group. Which alkene could be polymerised to make polymer G? A but-1-ene B but-2-ene C methylpropene D propene

The mass spectrum of compound X has M, M+1 and M+2 peaks. Other peaks are also present. Peak M is the molecular ion peak, ${\mathrm{M}}^{+}$. Peak M has a relative abundance fifteen times that of peak M+1. Peaks M and M+2 are of equal height. What could be compound X? A 1-chloro-2,2-dimethylpentane B 2-chloro-3-methylpentane C 2-bromo-2-methylhexane D 3-bromo-2,2-dimethylbutane