AS & A Level Chemistry - 9701 Paper 1 2019 Summer Zone 3

Manganese and nitrogen can show a range of different oxidation states.
Calculate the sum of the oxidation states of Mn and N in each row of the table.
In which row is this sum the smallest?

[Table_1]

The mass spectrum of an alloy of copper and gold is shown.

Which expression can be used to calculate the relative atomic mass, $A_r$, of copper present in this sample?

Which atom has exactly three unpaired electrons?

Element W is in period three of the Periodic Table and has a solid, white oxide, X. X is thermally stable and has a very high melting point.
X is slightly soluble in water.
Which row describes the structure and bonding of X?
[Table_1]

Ethane, $\text{CH}_3\text{CH}_3$, and fluoromethane, $\text{CH}_3\text{F}$, have the same number of electrons in their molecules.
Their boiling points are given.

[Table_1]

What is responsible for this difference in boiling points?

The reaction pathway diagram for a chemical reaction is shown. Which statement is correct?

What changes in conditions or molecular properties make it more likely that gases approach ideal behaviour?

Ethanol can be oxidised to ethanal by dilute acidified dichromate(VI) ions.
The oxidation reaction equation is $\text{C}_2\text{H}_5\text{OH} \rightarrow \text{C}_2\text{H}_4\text{O} + 2\text{H}^+ + 2\text{e}^-$.
The reduction reaction equation is $\text{Cr}_2\text{O}_7^{2-} + 14\text{H}^+ + 6\text{e}^- \rightarrow 2\text{Cr}^{3+} + 7\text{H}_2\text{O}$.
Which equation is correct?

What is the correct expression for $K_c$ for the reaction shown?
$$ ext{I}_2( ext{aq}) + 2 ext{Fe}^{2+}( ext{aq}) ightleftharpoons 2 ext{I}^-( ext{aq}) + 2 ext{Fe}^{3+}( ext{aq})$$

X and Y react together to form Z in a reversible reaction.
The equilibrium yield of Z is lower at higher temperature.
The equilibrium yield of Z is lower at lower pressure.
Which equation could represent this reaction?

The volume of carbon dioxide collected by reacting 0.100 mol of magnesium carbonate with 50.0 cm^3 of 1.00 mol dm^-3 sulfuric acid is measured against time. The volume produced is plotted against time and the line labelled P on the graph is obtained.
The experiment is repeated using 0.100 mol of the same magnesium carbonate, and a different sample of acid. All other conditions remain the same. Plotting these results gives the line labelled Q.
Which sample of acid could give the line labelled Q?

Sodium and sulfur react together to form sodium sulfide, Na$_2$S. How do the atomic radius and ionic radius of sodium compare with those of sulfur? [Table_1]

Which graph represents the variation in electronegativity for Period 3 elements?

Dilute hydrochloric acid is added to solid barium carbonate and solid magnesium carbonate in separate test-tubes.
Dilute sodium hydroxide is added to 0.1 mol dm^-3 barium chloride and 0.1 mol dm^-3 magnesium chloride in separate test-tubes.
Which row is correct? [Table_1]

River water in an agricultural area contains $\text{NH}_4^+$, $\text{CO}_3^{2-}$, $\text{HCO}_3^-$, $\text{Cl}^-$ and $\text{NO}_3^-$ ions. In a water treatment plant, this water is treated by adding a calculated quantity of calcium hydroxide. What is precipitated from the river water when calcium hydroxide is added?

The solids sodium chloride and sodium iodide both react with concentrated sulfuric acid at room temperature.
With NaCl, the products are NaHSO₄ and HCl.
With NaI, the products are NaHSO₄, HI, I₂, SO₂, H₂O, S and H₂S.
What is the explanation for this difference in products?

An aqueous solution of a calcium compound is treated with a mixture of dilute aqueous nitric acid and aqueous silver nitrate. The resulting white precipitate dissolves when dilute aqueous ammonia is added.
What is the relative molecular mass, $M_r$, of the calcium compound?

Which statement about the ammonium ion is correct?

In a catalytic converter 5.6 g of carbon monoxide reacts with an excess of nitrogen monoxide.
What is produced in this reaction?

The Finkelstein reaction occurs when NaI in propanone reacts with a chloroalkane or bromoalkane. The halogen is directly replaced by I. The reaction only works for primary halogenoalkanes.
Which halogenoalkane produces compound X?

The diagram shows the skeletal formula of compound Y.
What is the empirical formula of Y?

In polymer Z every carbon atom in the polymer chain is bonded to one hydrogen atom and one methyl group.
Which alkene could be polymerised to make polymer Z?

Which compound would produce a carboxylic acid and a ketone when treated with hot, concentrated acidified manganate(VII) ions?

Water is added to a sample of 2,3-dibromohexane. Some of the 2,3-dibromohexane undergoes complete hydrolysis and some of it undergoes partial hydrolysis.
What is not present in the mixture of products?

Which statement about the mechanism of an $S_N1$ reaction of a halogenoalkane is correct?

Structural isomerism and stereoisomerism should be considered when answering this question. Which isomer of $C_6H_{13}OH$ gives the greatest number of different alkenes when it is dehydrated?

Compound Q reacts with 2,4-dinitrophenylhydrazine to give a precipitate.
Compound Q does not produce a precipitate when warmed with Fehling's solution.
What could be the identity of compound Q?

Structural isomerism only should be considered when answering this question.
A set of isomeric compounds, with molecular formula $C_5H_{10}O$, all react in a 1:1 ratio with an excess of HCN by nucleophilic addition.
How many isomeric compounds are in the set?

Which pair of substances could react to give the ester $\text{CH}_3\text{CH}_2\text{CO}_2\text{CH}_3$?

An ester is shown.

What is the structure of the carboxylic acid that would be obtained by acid hydrolysis of the ester linkage?

Which deductions about the $^{209}_{83}\text{Bi}$ atom are correct?
1. It has 83 electrons.
2. It has 126 nucleons.
3. It has 83 neutrons.

Which statements are correct when referring to the two common isotopes of chlorine?
1. The isotopes have different masses.
2. The isotopes have different numbers of nucleons.
3. The isotopes have the same chemical reactions.

For which enthalpy changes is the value of $\Delta H$ always negative?

Which statements are correct?

1. The shaded area represents the proportion of molecules with energies between $E_1$ and $E_2$ at temperature $T_2$.
2. No particles have zero energy at either temperature.
3. $T_2$ is a higher temperature than $T_1$.

The diagram shows the Boltzmann distribution of molecular energies in one mole of a gas at two temperatures, $T_1$ and $T_2$.

Which statements about sodium chloride are correct?
1. It is a product of the reaction between chlorine and cold aqueous sodium hydroxide.
2. It is a product of the reaction between chlorine and hot aqueous sodium hydroxide.
3. It is a product of the reaction between chlorine and aqueous sodium bromide.

Which gases will dissolve in water causing a lowering of the pH?

Which compounds have optical isomers?

Bromine reacts with ethene in an addition reaction. Which statements about this reaction are correct?
1. It is the basis of a test for unsaturation in alkenes.
2. It leads to an increase in each of the H−C−H bond angles.
3. A nucleophile attacks the C=C bond in ethene.

An unknown organic compound Z reacts with sodium to give a combustible gas as one product. Z does not give a yellow precipitate with alkaline aqueous iodine. What is a possible identity of Z?

An organic molecule X has a molecular formula of $C_5H_{10}O_2$. Its infra-red spectrum has a strong peak at $1250\text{ cm}^{-1}$, a strong peak at $1720\text{ cm}^{-1}$ but no strong peak above $3100\text{ cm}^{-1}$.
What could X be?