AS & A Level Chemistry - 9701 Paper 1 2013 Summer Zone 3

In the redox reaction shown, how do the oxidation states of vanadium and sulfur change?
$$\text{VO}_2^+ + \text{SO}_2 \rightarrow \text{V}^{3+} + \text{SO}_4^{2-}$$
[Table_1]

Use of the Data Booklet is relevant to this question.
In which species are the numbers of protons, neutrons and electrons all different?

The first six ionisation energies of four elements are given. Which element is most likely to be in Group IV of the Periodic Table? [Table_1]

The diagram represents, for a given temperature, the Boltzmann distribution of the kinetic energies of the molecules in a mixture of two gases that will react together. The activation energy for the reaction, $E_a$, is marked.

The dotted curves below show the Boltzmann distribution for the same reaction at a higher temperature. On these diagrams, $H$ represents the activation energy at the higher temperature.
Which diagram is correct?

Crotonaldehyde, CH$_3$CH=CHCHO, can be obtained by oxidising butadiene, CH$_2$=CHCH=CH$_2$, using air or oxygen. One method is to pass a mixture of butadiene and oxygen through a hot aqueous solution of palladium(II) ions, Pd$^{2+}$(aq), which catalyse the reaction. Which statement is not correct about the action of the Pd$^{2+}$(aq) ions?

Which least resembles an ideal gas at room temperature and pressure?

Use of the Data Booklet is relevant to this question.
When 0.15 g of an organic compound is vaporised, it occupies a volume of 65.0 cm³ at 405 K and 1.00 \times 10^5 Nm^{-2}.
Using the expression $pV = nRT$, which of the following expressions should be used to calculate the relative molecular mass, $M_r$, of the compound?

Which compound is the only gas at room temperature and pressure?

Which formula represents the empirical formula of a compound?

Use of the Data Booklet is relevant to this question.
A washing powder contains sodium hydrogencarbonate, NaHCO₃, as one of the ingredients. In a titration, a solution containing 1.00g of washing powder requires 7.15 cm³ of 0.100 mol dm⁻³ sulfuric acid for complete reaction. The sodium hydrogencarbonate is the only ingredient that reacts with the acid.
What is the percentage by mass of sodium hydrogencarbonate in the washing powder?

Use of the Data Booklet is relevant to this question. This question should be answered using bond enthalpy data. The equation for the complete combustion of methanal is given below.

$\text{H}_2\text{C}=\text{O} + \text{O}_2 \rightarrow \text{CO}_2 + \text{H}_2\text{O}$

What is the enthalpy change of combustion of methanal?

Use of the Data Booklet is relevant to this question.
Anhydrous magnesium nitrate, Mg(NO_3)_2, will decompose when heated, giving a white solid and a mixture of two gases X and Y.
Y is oxygen.
What is the ratio $$\frac{\text{mass of } X \text{ released}}{\text{mass of } Y \text{ released}}$$?

In which row of the table are all statements comparing magnesium and barium correct? [Table_1]

Two students, P and Q, were asked to draw bar charts to represent how some properties of the halogens and their compounds differ in magnitude. Their diagrams are shown. Which of the student’s diagrams are correct?

When iodine is heated, a vapour is produced.
Which row of the table correctly identifies the species in the vapour and its colour?
[Table_1]

How do the strengths of the covalent bonds within molecules, and the van der Waals' forces between molecules, vary going down Group VII from chlorine to bromine to iodine?
[Table_1]

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?

In a famous experiment, Wöhler heated ‘inorganic’ ammonium cyanate in the absence of air. The only product of the reaction was ‘organic’ urea, CO(NH_2)_2. No other products were formed in the reaction.

What is the formula of the cyanate ion present in ammonium cyanate?

Transition elements and their compounds are important as catalysts.
In which process is a transition element compound used, rather than the element itself?

Ethene reacts with steam in the presence of sulfuric acid.
$$ ext{C}_2 ext{H}_4 + ext{H}_2 ext{O} ightarrow ext{CH}_3 ext{CH}_2 ext{OH}$$
What type of reaction is this?

What is true of every nucleophile?

How many isomers, including structural and stereoisomers, with the formula $C_4H_8$ have structures that involve $\pi$ bonding?

Burnt sugar has a characteristic smell caused partly by the following compound. This compound contains two functional groups. Which reagent will react with both functional groups?

Which sequence of reagents may be used in the laboratory to convert propan-1-ol into 2-bromopropane?

A carbanion is an organic ion in which a carbon atom has a negative charge. A carbocation is an organic ion in which a carbon atom has a positive charge.
What is involved in the mechanism of the reaction between aqueous sodium hydroxide and 2-bromo-2-methylbutane?

Which compound gives an organic product with a lower boiling point when it is heated under reflux with an excess of acidified potassium dichromate(VI)?

Which volume of oxygen, at room temperature and pressure, is needed for complete combustion of 0.1 mol of ethanol?

Cyclohexene, shown below, can form an addition polymer.

[Image showing cyclohexene structure]

Which structure represents a section of the polymer including two cyclohexene residues?

How many isomeric esters, including structural isomers and stereoisomers, can be made with the molecular formula $C_5H_{10}O_2$, if methanoic acid is one of the two reactants used?

CCl_2FCClF_2 can be converted into CH_2FCF_3 by the following route.

What type of reaction is step 1?

A space shuttle’s upward thrust came from the following reaction between aluminium and ammonium perchlorate. $$ 10Al + 6NH_4ClO_4 \to 4Al_2O_3 + 2AlCl_3 + 12H_2O + 3N_2 $$ Which statements about this reaction are correct? 1. Aluminium is oxidised. 2. Chlorine is reduced. 3. Nitrogen is oxidised.

Use of the Data Booklet is relevant to this question.
Which statements are correct when referring to the atoms $^{23}\text{Na}$ and $^{24}\text{Mg}$?
1. They have the same number of full electron orbitals.
2. They have the same number of neutrons.
3. They are both reducing agents.

The reaction pathway for a reversible reaction is shown below.
[Image_1: diagram of energy vs. extent of reaction with 50 kJ mol^-1 and 20 kJ mol^-1 markers]
Which statements are correct?
1. The enthalpy change for the backward reaction is -20 kJ mol^-1.
2. The forward reaction is endothermic.
3. The activation energy for the forward reaction is +70 kJ mol^-1.

Which diagrams represent part of a giant molecular structure?

Solids W, X, Y and Z are compounds of two different Group II metals. Some of their applications are described below.

Compound W is used as a refractory lining material in kilns.

Compound X is used as a building material. It can also be heated in a kiln to form compound Y. When Y is hydrated, it forms compound Z which is used agriculturally to treat soils.

Which statements about these compounds are correct?

1 More acid is neutralised by 2.0 g of X than by 2.0 g of W.
2 The $M_r$ of X is greater than the $M_r$ of Y by 44.0.
3 The metallic element in Y reacts with cold water more quickly than the metallic element in W.

Element $J$ is a solid. It occurs as a contaminant of fossil fuels.
Its oxide $K$ is formed in car engines.
In the atmosphere, $K$ can be further oxidised to $L$.
Which statements about $J$, $K$ and $L$ are correct?
1. Atoms of $J$ have paired $p$ electrons.
2. The atmospheric oxidation of $K$ to $L$ is a catalysed reaction.
3. With water, $L$ forms a strong acid.

During the bromination of methane, the free radical $\text{CH}_3\cdot$ is generated. A possible terminating step of this reaction is the formation of $\text{C}_2\text{H}_6$ by the combination of two free radicals.
What could be produced in a terminating step during the bromination of propane?

Fabrics for use in aircraft seating are treated with a coating containing a halogenoalkane.
Why is this coating used?
1. The treated fabric burns less easily, improving safety.
2. The treated fabric forms hydrogen bonds to water more readily, so it is easier to wash.
3. The halogenoalkane undergoes addition polymerisation, stiffening the fabric.

A liquid X is known to be either a single organic compound or a mixture of organic compounds.
When treated with sodium, X gives off hydrogen gas.
When treated with 2,4-dinitrophenylhydrazine reagent, X gives orange crystals.
Which deductions about X can definitely be made?

Ethanoic acid, $\text{CH}_3\text{CO}_2\text{H}$, is an important chemical which is used in the industrial manufacture of rayon and aspirin.
Which processes can be used to make ethanoic acid?
1. hydrolysis of ethanenitrile
2. oxidation of ethanol
3. oxidation of ethanal