AS & A Level Chemistry - 9701 Paper 1 2010 Winter Zone 1

Every year millions of tonnes each of chlorine and sodium hydroxide are manufactured by the electrolysis of brine using a 'diaphragm cell'.
What is the purpose of the diaphragm in such a cell?

A simple ion X^+ contains eight protons. What is the electronic configuration of X^+?

Equations involving four enthalpy changes are shown.

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

What is the second ionisation energy of sodium?

Sulfur dioxide, SO$_2$, is added to wines to prevent oxidation of ethanol by air. To determine the amount of SO$_2$, a sample of wine is titrated with iodine, I$_2$. In this reaction, one mole of SO$_2$ is oxidised by one mole of I$_2$. What is the change in oxidation number of sulfur in this reaction?

Use of the Data Booklet is relevant to this question.
Nickel makes up 20\% of the total mass of a coin. The coin has a mass of 10.0 g.
How many nickel atoms are in the coin?

Which ion has more electrons than protons and more protons than neutrons?
[H = $^{1}_{1}$H ; D = $^{2}_{1}$H ; O = $^{16}_{8}$O]

Organic nitrates in photochemical smog can cause breathing difficulties. The diagram shows an example of an organic nitrate molecule.
What is the correct order of the bond angles shown in ascending order (smallest first)?

Enthalpy changes of combustion can be used to determine enthalpy changes of formation. The following equation represents the enthalpy change of formation of butane.

$$4C(s) + 5H_2(g) \to C_4H_{10}(g)$$

By using the following standard enthalpy of combustion data, what is the value of the standard enthalpy change of formation, $\Delta H_f^\circ$, for this reaction?

[Table_1]

In a calorimetric experiment 1.60 g of a fuel is burnt. 45% of the energy released is absorbed by 200 g of water whose temperature rises from 18°C to 66°C. The specific heat capacity of water is 4.2 J g^-1 K^-1.
What is the total energy released per gram of fuel burnt?

The value of the equilibrium constant, $K_c$, for the reaction to form ethyl ethanoate from ethanol and ethanoic acid is 4.0 at 60°C.
$$\text{C}_2\text{H}_5\text{OH} + \text{CH}_3\text{CO}_2\text{H} \rightleftharpoons \text{CH}_3\text{CO}_2\text{C}_2\text{H}_5 + \text{H}_2\text{O}$$
When 1.0 mol of ethanol and 1.0 mol of ethanoic acid are allowed to reach equilibrium at 60 °C, what is the number of moles of ethyl ethanoate formed?

Which equation represents the change corresponding to the enthalpy change of atomisation of iodine?

Camphor is a white solid which was used to make the early plastic celluloid. Camphor contains the same percentage by mass of hydrogen and oxygen.
What is the molecular formula of camphor?

Why is the first ionisation energy of phosphorus greater than the first ionisation energy of silicon?

When magnesium nitrate, Mg(NO_3)_2·7H_2O, is heated, which three gases are given off?

Ammonium sulfate in nitrogenous fertilisers in the soil can be slowly oxidised by air producing sulfuric acid, nitric acid and water.
How many moles of oxygen gas are needed to oxidise completely one mole of ammonium sulfate?

Chile saltpetre, NaNO_3, contains sodium iodide as an impurity. Aqueous silver nitrate is added to an aqueous solution of Chile saltpetre. Concentrated aqueous ammonia is then added. Which observations are made? [Table_1]

Which statement describes the halogens chlorine, bromine and iodine?

Sulfur dioxide is used to bleach wood pulp in the production of paper. It is also used as an additive in the production of jam and marmalade, often in the form of sulfite compounds. When it is present in quantities greater than 10 mg / kg it is required to be listed as an ingredient of the jam. Why is sulfur dioxide added to jam?

Which property of beryllium and its compounds is typical of the elements below it in Group II?

One of the characteristics of addition polymerisation is that the empirical formulae of the polymer and of its monomer are the same. The absorbent material in babies’ disposable nappies is made from the addition polymer shown.

From which monomer could this addition polymer be obtained?

Compound X reacts with ethanoic acid in the presence of an $H^+$ catalyst to produce the compound below.

What is the molecular formula of compound X?

A compound Y has all of the properties below.
• It is a liquid at 25°C.
• It mixes completely with water.
• It reacts with aqueous sodium hydroxide.
What could Y be?

Tartaric acid is present in some wines. It may be synthesised in the laboratory in two steps.

$$\text{OHCHCHO} \xrightarrow{\text{step 1}} \text{intermediate} \xrightarrow{\text{step 2}} \text{HO}_2\text{CCH(OH)CH(OH)CO}_2\text{H}$$

Tartaric acid

Which reagents could be used for this synthesis?

[Table_1]

Which alcohol gives only one possible oxidation product when warmed with dilute acidified potassium dichromate(VI)?

Limonene is an oil formed in the peel of citrus fruits.


Which product is formed when an excess of bromine, $Br_2(l)$, reacts with limonene at room temperature in the dark?

Lactic acid occurs naturally, for example in sour milk.
What is a property of lactic acid?

Which compound would undergo nucleophilic addition?

Which compound undergoes an $S_N1$ substitution reaction?

The compound 2-methylpropene, $C_4H_8$, is a monomer used in the production of synthetic rubber.

In addition to 2-methylpropene, there are x other isomers of $C_4H_8$, structural or otherwise, which contain a double bond.
What is the value of x?

Which environmental problem is not made worse by the release of oxides of nitrogen from car engines?

Ethanol is manufactured by reacting ethene gas and steam in the presence of phosphoric(V) acid.

The reaction is carried out at 570 K and 60 atm.
What would be the consequences of carrying out the reaction at the same temperature but at a pressure of 200 atm?
1. The manufacturing costs would increase.
2. The maximum yield at equilibrium would be higher.
3. The reaction would proceed at a faster rate.

The diagram represents the Boltzmann distribution of molecular energies at a given temperature.
Which of the factors that affect the rate of a reaction can be explained using such a Boltzmann distribution?
1 increasing the concentration of reactants
2 increasing the temperature
3 the addition of a catalyst

Which types of intermolecular forces can exist between adjacent urea molecules?

Samples of calcium and barium are separately added to beakers of cold water containing a few drops of litmus solution.
Which observations will be made with only the calcium and not with the barium?

Disproportionation is the term used to describe a reaction in which a reactant is simultaneously both oxidised and reduced.
To which incomplete equations does the term disproportionation apply?
1 $Cl_2(g) + 2OH^-(aq) \rightarrow H_2O(l) + Cl^-(aq) + \cdots$
2 $3Cl_2(g) + 6OH^-(aq) \rightarrow 3H_2O(l) + ClO_3^-(aq) + \cdots$
3 $2NO_2(g) + H_2O(l) \rightarrow HNO_3(aq) + \cdots$

Element X is a solid. It occurs as a contaminant of carbonaceous fuels. Its oxide Y is formed in car engines. Further oxidation of Y to Z can occur in the atmosphere. Which statements about Y and Z are correct?
1. Molecule Y has lone pairs of electrons.
2. The atmospheric oxidation of Y to Z is a catalysed reaction.
3. Y is a colourless gas.

The diagram shows the structure of the naturally-occurring molecule cholesterol. Which statements about cholesterol are correct?
1. The molecule contains a secondary alcohol group.
2. The molecule contains two \( \pi \) bonds.
3. All carbon atoms in the four rings lie in the same plane.

Glyceraldehyde, HOCH₂CH(OH)CHO, is formed during photosynthesis, and contains a chiral carbon atom. Which reagents will react with glyceraldehyde to produce an organic product \textbf{without} a chiral carbon atom?

An organic compound decolourises aqueous bromine and reacts with sodium to produce hydrogen.
Which molecular formula could represent this compound?

Textiles for use in aircraft are treated with a finish containing a halogenoalkane.
What is the reason for this?
1. The textile burns less easily, improving safety.
2. The fabric forms hydrogen bonds to water more readily, making the fabric easier to wash.
3. The halogenoalkane undergoes addition polymerisation, stiffening the fabric.