AS & A Level Chemistry - 9701 Paper 1 2024 Summer Zone 1

Sample X is added to water and made up to a total volume of 200 cm³. This gives a solution of 0.100 mol dm⁻³ HCl.
What is X?

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?

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?

Which statement about $^{131}_{53}\text{I}$ is correct?

When solid aluminium chloride is heated, $Al_2Cl_6$ is formed.
Which bonding is present in $Al_2Cl_6$?

The structure of the sulfur dioxide molecule is shown.
What is the shape of the sulfur dioxide molecule?

What is the density of a sample of fluorine gas at 32\(^\circ\)C and 100000Pa? Assume fluorine behaves as an ideal gas under these conditions.

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?

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?

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), Na$_2$CrO$_4$, is manufactured by heating chromite, FeCr$_2$O$_4$, with sodium carbonate in an oxidising atmosphere. Chromite contains Cr$_2$O$_4^{2-}$ ions.

$$2 ext{FeCr}_2 ext{O}_4 + 4 ext{Na}_2 ext{CO}_3 + 3rac{1}{2} ext{O}_2 ightarrow 4 ext{Na}_2 ext{CrO}_4 + ext{Fe}_2 ext{O}_3 + 4 ext{CO}_2$$

What happens in this reaction?

Oxygen can be prepared by the reaction of potassium manganate(VII), KMnO4, hydrogen peroxide, H2O2, and sulfuric acid, H2SO4. Each H2O2 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 mol of KMnO4 reacts with an excess of H2O2 in acidic conditions?

An alcohol, 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 mol of ROH, 2.0 mol of ethanoic acid and 1.0 mol of water are mixed together. At equilibrium, 1.5 mol of CH$_3$COOR is present.

What is the value of the equilibrium constant, $K_c$, for this reaction?

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 pH 2 is produced.
When the chloride of element Z is added to water, it dissolves and a solution of pH 7 is produced.
Which statement explains these observations?

Aluminium, silicon and phosphorus are elements in Period 3 of the Periodic Table. Each element forms an oxide.
Which row is correct?
[Table_1]

Which statement is correct?

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.

[Table_1]

What is the missing data for element X?

What is the total volume of gas produced, measured at room conditions, when 0.010 mol of anhydrous magnesium nitrate is completely decomposed by heating?

A solid sodium halide, NaX, is reacted with concentrated sulfuric acid. The lowest oxidation state of sulfur in the products is +4.
Halogen Y₂ is less volatile than halogen X₂.
What are the identities of sodium halide NaX and halogen Y₂?

Compound Q dissolves in water. Q(aq) does not react with dilute sulfuric acid.
Q(aq) forms a precipitate when aqueous silver nitrate is added. This precipitate is partially soluble in aqueous ammonia.
What could be compound Q?

Nitrogen dioxide is a gas that contributes to air pollution. It is produced in internal combustion engines.
Which statement is correct?

What is the bond angle in the ammonium ion?

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 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?
[Table_1]

The diagram shows the structure of X.



Which row is correct?

[Table_1]

The diagram shows the skeletal formula of citric acid.

What is the molecular formula of citric acid?

Which reaction occurs when ethane and chlorine are mixed in diffused sunlight?

A molecule of geraniol is shown.

What is formed when geraniol is reacted with an excess of cold dilute acidified 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?
[Table_1]

2-bromopropane is converted to 1,2-dibromopropane in a pathway involving two reactions.
reaction 1: 2-bromopropane $\rightarrow$ compound X
reaction 2: compound X $\rightarrow$ 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?

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 NaBH₄, the organic product has a $M_r$ 2.3256% greater than the $M_r$ of ketone X.
• Ketone X gives a yellow precipitate with alkaline $I_2$(aq).
How many isomeric ketones could be ketone X?

Compound Y:
• changes the colour of acidified $K_2Cr_2O_7$ 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?

P is a carboxylic acid with molecular formula $C_5H_{10}O_2$.
Carboxylic acid P reacts with an excess of $LiAlH_4$ to form compound Q.
Which pairs of molecules could be carboxylic acid P and compound Q?
[Table_1]

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?

The relative atomic mass of antimony is 121.76.
Antimony has \textbf{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 \textbf{higher} mass number?