AS & A Level Chemistry - 9701 Paper 1 2024 Winter Zone 2

Which species contains a different number of electrons from the other three?

Which factor causes helium to have a higher first ionisation energy than hydrogen?

A 0.216 g sample of aluminium carbide reacts with an excess of water to produce methane gas. This is the only carbon-containing product formed in the reaction. This methane gas burns completely in $O_2$ to form $H_2O$ and $CO_2$ only. The volume of $CO_2$ produced at room temperature and pressure is 108 cm³.
What is the formula of aluminium carbide?

A reaction between two gases takes place on the surface of the catalytic converter of a petrol-engined car.
In this reaction, four reactant molecules produce three product molecules.
What could be the two reactant gases in this reaction?

An ion contains 1 nitrogen atom and 2 hydrogen atoms. It has an H–N–H bond angle of approximately 105°. Which row is correct?
[Table_1]

Why does ICl have a higher boiling point than Br_2?

In this question you may assume that nitrogen behaves as an ideal gas. One atmosphere pressure = 101 kPa.
Which volume does 1.0 g of nitrogen occupy at 50°C and a pressure of 2.0 atmospheres?

Which statement about the properties associated with the different types of bonding involved is correct?

For which reaction is the enthalpy change an enthalpy change of formation?

Two standard enthalpy change of formation values are given.

$\Delta H_f^{\circ} [\text{VCl}_2] = -452 \text{kJ mol}^{-1}$
$\Delta H_f^{\circ} [\text{VCl}_3] = -573 \text{kJ mol}^{-1}$

What is the enthalpy change for the reaction $3\text{VCl}_2 \rightarrow 2\text{VCl}_3 + \text{V}$?

Equations for some reactions of hydrogen peroxide are given.

1. $2\text{Fe}^{2+} + \text{H}_2\text{O}_2 + 2\text{H}^+ \rightarrow 2\text{Fe}^{3+} + 2\text{H}_2\text{O}$
2. $2\text{MnO}_4^- + 5\text{H}_2\text{O}_2 + 6\text{H}^+ \rightarrow 2\text{Mn}^{2+} + 8\text{H}_2\text{O} + 5\text{O}_2$
3. $2\text{Fe}^{3+} + \text{H}_2\text{O}_2 + 2\text{OH}^- \rightarrow 2\text{Fe}^{2+} + \text{O}_2 + 2\text{H}_2\text{O}$

In which reactions is hydrogen peroxide acting as a reducing agent?

The equation for the reaction of aqueous thiosulfate ions, ${{\text{S}}_2{{\text{O}}_3}^{2-}}$, and aqueous dioxo-vanadium ions, ${{\text{VO}}_2}^{+}$, is shown.

$${{\text{2S}}_2{{\text{O}}_3}^{2-}} + x{{\text{VO}}_2}^{+} + y\text{H}^{+} \rightarrow {{\text{S}}_4{{\text{O}}_6}^{2-}} + z{{\text{VO}}^{2+}} + \text{2H}_2\text{O}$$
Which row shows two correct statements about the equation for this reaction?
[Table_1]

When some solid Ca$_5$(PO$_4$)$_3$OH is added to a beaker of water, an equilibrium is set up.

Ca$_5$(PO$_4$)$_3$OH(s) $\rightleftharpoons$ 5Ca$^{2+}$(aq) + 3PO$_4$$^{3-}$(aq) + OH$^-$(aq)

Which compound, when added to the equilibrium mixture, increases the amount of Ca$_5$(PO$_4$)$_3$OH(s) present?

Gaseous hydrogen and gaseous iodine react to form gaseous hydrogen iodide.

$\text{H}_2(g) + \text{I}_2(g) \rightleftharpoons 2\text{HI}(g)$

In an experiment, 2.0 mol of hydrogen and 2.0 mol of iodine are placed in a sealed container of volume 1.0 dm³.

The $K_c$ value for this reaction under the conditions used is 9.0.

How many moles of hydrogen iodide are present at equilibrium?

Why does the rate of a gaseous reaction increase when the pressure is increased at a constant temperature?

The Boltzmann distribution for a mixture of gases capable of reaction is shown.
The two curves represent the mixture of gases at 25°C and at 35°C. The activation energies for the catalysed and uncatalysed reactions are shown.

Which row is correct?

Which oxide is insoluble in aqueous sodium hydroxide?

Sodium and sulfur are burned separately in oxygen.
Each reaction has a distinctive coloured flame.
Which row is correct?

[Table_1]

X and Y are elements in Period 3 of the Periodic Table.
Y has a greater atomic number than X.
The stable ion formed by Y has a greater radius than the stable ion formed by X.
The stable ion formed by Y has 18 electrons.
Which row is correct?
[Table_1]

X is a Group 2 element in either Period 3 or Period 5. X(OH)_2 is less soluble in water than Ca(OH)_2.
When X(NO_3)_2 is heated, it decomposes.
Which row is correct?
[Table_1]

Which statement comparing magnesium and barium, or their compounds, is correct?

The colours of the silver halides AgCl, AgBr and AgI differ.
The solubilities of these halides in aqueous ammonia also differ.
Which row is correct?
[Table_1]

The name `chlorate` is used for an anion consisting of chlorine and oxygen only.
In a molecule of $ICl$, the iodine atom has oxidation number $x$ and the chlorine atom has oxidation number $y$.
When $ICl$ is added to $H_2O$, iodine is reduced.
$$4ICl + 2H_2O \rightarrow 4HCl + O_2 + 2I_2$$
Which statement about the value of $x$ or $y$ is correct?

Which statement is correct?

The diagram shows the structural formula of a hydrocarbon molecule Q.

How many of the carbon atoms in molecule Q are $sp^2$ hybridised?

Compound X is found in cell walls of some bacteria. Its structural formula is shown.

CH_3(CH_2)_{17}CH=CH(CH_2)_7CH(OH)CH(CH_3)CO_2H
How many stereoisomers are there with this structural formula?

Structural isomerism \textit{only} should be considered when answering this question.
How many straight-chain isomers are there with molecular formula $C_4H_8Cl_2$?

What is true of \textit{every} nucleophile?

The diagram shows a synthetic route to produce 1-methylcyclohexanol.

What is reagent Y?

X and Y are the reagents required to convert 1-bromopropane into butanoic acid.

What are the correct identities of reagents X and Y?

The table shows three sets of reagents and reaction conditions.

[Table_1]

Which sets of reagents and conditions can be used to produce 2-chloro-2-methylpropane as one of the organic products?

What are the \textit{only} structures formed when butan-2-ol is heated with concentrated $\text{H}_2\text{SO}_4$?

The compound 'leaf alcohol' is partly responsible for the smell of new-mown grass.

leaf alcohol
$\text{CH}_3\text{CH}_2\text{CH}=\text{CHCH}_2\text{OH}$

What will be formed when 'leaf alcohol' is oxidised using an excess of hot acidified $\text{K}_2\text{Cr}_2\text{O}_7\text{(aq)}$?

Compound X:
• does not react with Tollens’ reagent
• forms a yellow precipitate with alkaline $I_2(aq)$
• does not react with sodium.

What could be the identity of X?

Which compound can undergo nucleophilic addition?

C$_2$H$_5$COOCH$_3$ is reacted with aqueous acid.
The products from this reaction are reacted with LiAlH$_4$ to form two molecules Y and Z.
What are the identities of molecules Y and Z?

A sample of propanoic acid of mass 3.70 g reacts with an excess of magnesium.
A second sample of propanoic acid of mass 3.70 g reacts with an excess of sodium.
Both reactions go to completion forming a gas.
Which row is correct?
[Table_1]

Which statement about $\text{H}_2\text{C} = \text{C}( ext{CH}_3)\text{CH}_2\text{CO}_2\text{CH}_3$ is correct?

Synthetic resins can be made by polymerisation of a variety of monomers including prop-2-en-1-ol, $CH_2=CHCH_2OH$.
Which structure represents the repeat unit in the polymer poly(prop-2-en-1-ol)?

Vitamin C has the structure shown.
The mass spectrum of vitamin C has a molecular ion peak with an $m/e$ value of 176 and a relative abundance of 7.0%.
What is the abundance of the M +1 peak?