AS & A Level Chemistry - 9701 Paper 1 2022 Summer Zone 2

Equations involving four enthalpy changes are shown.

$\text{Na(g) } \rightarrow \text{ Na}^+\text{(g) } + \text{e}^- \quad \Delta H = W$
$\text{Na(g) } \rightarrow \text{ Na}^{2+}\text{(g) } + 2\text{e}^- \quad \Delta H = X$
$\text{Na(s) } \rightarrow \text{ Na(g) } \quad \Delta H = Y$
$\text{Na(s) } \rightarrow \text{ Na}^{2+}\text{(g) } + 2\text{e}^- \quad \Delta H = Z$

Which equation represents the second ionisation energy of sodium?

This question refers to isolated gaseous atoms in the ground state.
In which atom are all electrons paired?

Which sample contains the most iodine?

When a small sample of hydrocarbon Q is completely combusted, it produces 3.52 g of carbon dioxide and 1.44 g of water. What could be the structure of hydrocarbon Q?

Ethane and ethene are both hydrocarbon molecules.
What is a feature of both molecules?

Elements J and L are both in Group 15.
J and L each form a gaseous covalent hydride in which their oxidation number is -3.
In the liquefied forms of these hydrides, significant hydrogen bonding occurs only in the hydride of L.
Which row about J and L could be correct?
[Table_1]

Which gas will behave least like an ideal gas at 150°C and 101 kPa?

When an evacuated glass bulb of volume 200cm³ is filled with a gas at 300K and 101kPa, the mass of the bulb increases by 0.68g. The gas obeys the ideal gas equation.
What is the identity of the gas?

The standard enthalpy of formation of NO$_2$(g) is +33.2 kJ mol$^{-1}$.
The standard enthalpy of formation of N$_2$O$_4$(g) is +9.2 kJ mol$^{-1}$.
What is the standard enthalpy change for the reaction 2NO$_2$(g) $ ightarrow$ N$_2$O$_4$(g)?

Separate samples of 25.0 cm$^3$ of 0.1 mol dm$^{-3}$ NaOH(aq) are added to each of three different acid solutions, as described. The temperature of each of the solutions was 298 K before mixing.
[Table_1]
Which statement describes the temperature rises that occur on mixing each of these three acids separately with NaOH?

NCl_3 reacts with H_2O.
$$ \text{NCl}_3 + 3\text{H}_2\text{O} \rightarrow \text{NH}_3 + 3\text{HClO} $$
The oxidation state of nitrogen does not change in this reaction.
Which statement is correct?

In which row do the oxidation numbers of vanadium increase?
[Table showing rows A to D with oxidation states displayed]

A synthesis for methanol is shown.
$\text{CO}_2 + 3\text{H}_2 \rightleftharpoons \text{CH}_3\text{OH} + \text{H}_2\text{O} \quad \Delta H = -49\text{ kJ mol}^{-1}$
Which conditions would produce the greatest yield of methanol at equilibrium?
[Table_1]

Hydrogen and iodine can react reversibly to produce hydrogen iodide. The equation is shown.

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

4.00 mol of hydrogen gas and X mol of iodine vapour are mixed in a sealed container of volume 1.00 dm$^3$ at a temperature of 460 K. The system is allowed to reach equilibrium.

The equilibrium mixture contains 2.00 mol of hydrogen iodide. The equilibrium constant, $K_c$, for the reaction at 460 K is 4.0.

What is the value of X?

A large amount of $\text{N}_2\text{O}(g)$ decomposes into nitrogen gas and oxygen gas in the presence of a tiny amount of a gold foil catalyst.
The gold foil provides a solid surface on which the catalysed reaction takes place.
The graph shows the concentration of $\text{N}_2\text{O}(g)$ against time as it decomposes. The graph is a straight line.



Which row describes:

• the change in rate of reaction as $\text{N}_2\text{O}(g)$ decomposes from 0 to 10 minutes
• the effect of adding more gold foil catalyst on the rate of decomposition of the same amount and concentration of $\text{N}_2\text{O}(g)$?

The Haber process for the manufacture of ammonia is represented by the equation shown.
$$ \text{N}_2(g) + 3\text{H}_2(g) \rightleftharpoons 2\text{NH}_3(g) \quad \Delta H = -92 \, \text{kJ mol}^{-1} $$
Which statement is correct about this reaction when the temperature is increased?

NH$_3$(aq) is added to separate samples of NaCl(aq), MgCl$_2$(aq), BaCl$_2$(aq) and SiCl$_4$(l). Under the conditions of this experiment, only two samples will produce a white precipitate when NH$_3$(aq) is added.
What are these two samples?

Why is the ionic radius of a sulfide ion larger than the ionic radius of a potassium ion?

Which graph correctly shows relative electronegativity plotted against relative atomic radius for the elements Na, Mg, Al and Si?

The table gives information about calcium carbonate and calcium hydroxide.
Which row is correct?

[Table_1]
calcium carbonate is more soluble in water than calcium hydroxide
calcium hydroxide can be manufactured using calcium carbonate as a starting material

Q is a Group 2 metal.
An excess of QCO$_3$(s) is added to H$_2$SO$_4$(aq) followed by filtration. A sample of QSO$_4$ is then obtained by evaporation of the filtrate.
What could be the identity of Q?

X, Y and Z are three elements in Group 17.
X_2 has weaker covalent bonds than Y_2.
X_2 has stronger instantaneous dipole-induced dipole forces between its molecules than Z_2.
Y_2 is a stronger oxidising agent than Z_2.
What could be X, Y and Z?
[Table_1]

Chlorine reacts with aqueous sodium hydroxide forming two chlorine-containing products.
Which row shows the oxidation states of chlorine in the products under the conditions stated?
[Table_1]

A catalytic converter reduces the amount of pollutants in the fumes from a car exhaust.
Which row identifies a pollutant and shows how it is removed by the action of the catalyst?
[Table_1]

Solid R is added to a solution of ammonium nitrate and the mixture is heated. A gas is given off which turns red litmus to blue. What could be R?

A skeletal formula is shown.
What is the total number of stereoisomers including the one shown?

The molecular formula $\text{CH}_3$ can represent an anion, a cation or a free radical. Species with the molecular formula $\text{CH}_3$ can act as an electrophile, a free radical or a nucleophile depending on the number of outer shell electrons on the central carbon atom.
How many outer shell electrons on the central carbon atom must be present for $\text{CH}_3$ to act in these different ways?
[Table_1]

Compound Z, $\text{C}_7\text{H}_{13}\text{Br}$, has two chiral centres. A sample of Z contains all four possible optical isomers.
This sample of Z reacts with hot ethanolic NaOH to produce a mixture of only three isomers. Two of these isomers are optical isomers of each other.
What could be the formula of Z?

The free-radical substitution reaction between methane and chlorine involves initiation, propagation and termination stages.
Which row is correct?
[Table_1]

The alkene shown reacts with an excess of HBr via an electrophilic addition reaction.
What is the major product formed?

The diagram shows the structures of two halogenoalkanes, P and Q.



Both compounds can be hydrolysed.
Which row is correct?

The structure of coniine is shown.

Coniine can be synthesised by reacting ammonia with a dibromo compound, X.
X
\[ \text{NH}_3 + \text{C}_8\text{H}_{16}\text{Br}_2 \rightarrow \text{coniine} + 2\text{HBr} \]
What is compound X?

Primary alcohols can be oxidised to aldehydes using either acidified potassium dichromate(VI) or acidified potassium manganate(VII). The reaction mixtures change colour as the oxidising agent is reduced.
What are the colour changes seen?

[Table_1]

Which reaction has a product that gives a yellow precipitate when treated with alkaline $I_2(aq)$?

The skeletal formula of M is shown.
M is reacted with an excess of LiAlH₄. Dilute acid is then added.
What is the molecular formula of the final organic product?

Which compound forms a precipitate when mixed with 2,4-DNPH reagent and also forms a precipitate when mixed with Fehling’s reagent?

Which reaction is a redox reaction?

Ethyl butanoate is a flavouring, with a fruity flavour.
Which row is correct?
[Table_1]

Cyclohexene, as shown in the diagram, can form an addition polymer.
[Image_1: Cyclohexene diagram]
Which structure represents a section of the polymer?

Three organic compounds are listed.

1. ethanal
2. propan-1-ol
3. propan-2-ol

Which compounds will have a mass spectrum that contains a fragment peak at $m/e = 43$?