Cambridge IGCSE Chemistry - 0620 - Supplement Paper 2 2024 Spring Zone 2

Solid X is heated for 600 seconds. The graph shows the heating curve that is obtained.
What is the melting point of X?

Which statements about diffusion are correct? 1. Aqueous ions cannot diffuse in water. 2. Diffusion is caused by the random movement of particles. 3. Particles spread out in all directions in diffusion. 4. Diffusion can only take place in solids and liquids.

Which statement about an atom of fluorine, $^{19}_{9}\text{F}$, is correct?

Two of the isotopes of calcium are represented as $^{40}_{20}\text{Ca}$ and $^{44}_{20}\text{Ca}$.

Which statement explains why these isotopes of calcium have identical chemical properties?

Which statement describes a property of potassium iodide?

Methanal, CH$_2$O, has a boiling point of $-19^{\circ}$C. At $-20^{\circ}$C, the liquid methanal is a non-conductor of electricity. In a sample of methanal, each atom of carbon, hydrogen and oxygen has noble gas electronic configuration. Each atom has achieved this electronic configuration in one of three ways: \begin{itemize} \item gaining electrons \item losing electrons \item sharing electrons. \end{itemize} Which statement describes the bonding between the carbon atom and the oxygen atom in methanal?

The structures of diamond and graphite are shown.
Which statement about diamond and graphite is correct?

Which row contains a description of metallic bonding and a property that is explained by reference to metallic bonding? [Table_1]

What is the relative molecular mass, $M_r$, of sulfur dioxide?

Magnetite is an ore of iron which contains the ions $\text{Fe}^{2+}$, $\text{Fe}^{3+}$, and $\text{O}^{2-}$ only. What is the formula of magnetite?

Concentrated aqueous sodium chloride and dilute sulfuric acid are both electrolysed using inert electrodes.
Which row identifies the product at the cathode in each electrolysis?
[Table_1]

Electrolytes can be broken down by electrolysis. Which rows are correct for each electrolyte?
[Table_1]
Table:
1. dilute aqueous potassium chloride: $2H^+ + 2e^- \rightarrow H_2$ (oxygen)
2. concentrated hydrochloric acid: $2H^+ + 2e^- \rightarrow H_2$ (chlorine)
3. molten aluminium oxide: $2O^{2-} \rightarrow O_2 + 4e^-$ (aluminium)
4. concentrated aqueous sodium bromide: $Na^+ + e^- \rightarrow Na$ (bromine)

Which statement about hydrogen–oxygen fuel cells is correct?

Which statement defines the activation energy, $E_a$, for a reaction?

The equation for the complete combustion of ethyne, H≡C−C≡H, is shown.

$2\text{H}−\text{C}≡\text{C}−\text{H} + 5\text{O}=\text{O} \rightarrow 4\text{O}=\text{C}=\text{O} + 2\text{H}−\text{O}−\text{H}$

The bond energies are listed.
[Table_1]
What is the enthalpy change of the reaction when 1 mol of ethyne is completely burned?

In experiment 1, small lumps of limestone are added to dilute ethanoic acid at 40 °C. The volume of carbon dioxide released is measured at regular time intervals. A graph of the results is shown. [Image_1: Graph showing volume of carbon dioxide released over time for experiments 1 and 2] Which changes give the results shown in experiment 2? [Table_1: Table listing options for limestone and temperature]

In the Haber process, nitrogen and hydrogen are reacted to make ammonia. $$\text{N}_{2}(g) + 3\text{H}_{2}(g) \rightleftharpoons 2\text{NH}_{3}(g)$$ The forward reaction is exothermic. Which conditions produce the maximum yield of ammonia? [Table_1]

The Ostwald process is used to make nitric acid.
The conditions used in this process are:
1. a catalyst containing a transition element
2. a pressure of 10 atm
3. a temperature of 800 °C.
Which of these conditions are also used in the Contact process?

Hydrogen iodide is dissolved in water. $$\text{HI} \rightarrow \text{H}^+ + \text{I}^-$$ Which row describes the final colours seen when the solution is tested with damp red litmus paper and with acidified aqueous potassium manganate(VII)? [Table_1]

Which statements about aqueous ethanoic acid are correct?
1. It can be produced by oxidising ethanol with potassium iodide.
2. It reacts with magnesium to produce hydrogen gas.
3. It has an approximate pH value of 3.
4. It produces esters called methanoates.

Which element forms an acidic oxide?

Which statement describes the properties of hydrochloric acid?

Elements P and Q have the same number of electron shells.
An atom of Q has more electrons in its outer electron shell than an atom of P.

Which statements are correct?

1. P and Q are in the same group of the Periodic Table.
2. P and Q are in the same period of the Periodic Table.
3. P has a greater tendency to form positive ions than Q.
4. The oxide of Q is more basic than the oxide of P.

Which substance reacts with dilute sulfuric acid to form a salt that can be removed from the resulting mixture by filtration?

Astatine is below iodine in Group VII in the Periodic Table. Which row describes the properties of astatine? [Table_1]

Which property of copper explains why it is classified as a transition element?

Brass is an alloy that is formed from copper and zinc. Which statements are correct?
1. Brass, copper and zinc all conduct electricity.
2. Brass is a compound of copper and zinc.
3. Brass is harder than zinc.

The equation for the reaction of metal M with aqueous zinc sulfate is shown.
M(s) + ZnSO$_4$(aq) \rightarrow MSO$_4$(aq) + Zn(s)
Which statement explains why metal M reacts with aqueous zinc sulfate?

In the blast furnace, the impurity silicon(IV) oxide is removed by the formation of slag. Which equation represents the formation of the substance which reacts with silicon(IV) oxide to form slag?

Aluminium is extracted from bauxite by electrolysis.
Which statement is correct?

Iron rusts but aluminium does not easily corrode. Which statement explains why aluminium does not easily corrode?

Which chemicals can be used as a fertiliser to provide the three elements needed for improved plant growth?

What is the colour change when water is added to anhydrous cobalt(II) chloride?

How do carbon dioxide and methane cause global warming?

Four statements about photosynthesis are listed.
1. Chlorophyll is required for photosynthesis.
2. The equation for photosynthesis is $C_6H_{12}O_6 + 6O_2 \rightarrow 6CO_2 + 6H_2O$.
3. Photosynthesis requires energy from light.
4. Photosynthesis releases carbon dioxide, which can lead to climate change.
Which statements are correct?

Which molecules are structural isomers?

Which statements about the reaction of ethene with steam are correct?
1. The product has a higher molecular mass than ethane.
2. The product reacts with aqueous bromine.
3. The number of electrons shared between carbon atoms decreases.
4. The reaction produces an alcohol and hydrogen.

Methane and chlorine react to form chloromethane.
Which row describes the necessary reaction condition and the type of reaction? [Table_1]

Parts of the structure of two different polymers, X and Y, are shown.
Which row about the monomers and the linkages between the monomers in polymers X and Y is correct?
[Table_1]

Substance Q is tested using paper chromatography. The resulting chromatogram is shown. [Image_1: Chromatogram diagram with solvent front and baseline marked] Which statement is correct?