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

Oxygen melts at $-219\degree C$ and boils at $-183\degree C$.
At which temperature is oxygen a liquid?

The pressure of a sample of gas is decreased. The temperature is kept constant. Which row describes the effects on the particles? [Table_1]

Rubidium has two isotopes, $^{85}_{37}\text{Rb}$ and $^{87}_{37}\text{Rb}$. Which statement explains why both isotopes have the same chemical properties?

Which pair of elements react to form a compound with a strong attraction between oppositely charged ions?

Four substances, P, Q, R and S, are described. • P is diatomic. • Q is a good conductor of electricity when solid and when molten. • R is a silver solid with a very high melting point. • S reacts with oxygen to form a brown gas. Which substances are metals?

Which diagram shows the covalent bonding in a molecule of carbon dioxide?

The bonding, structure and melting point of sodium chloride and sulfur dichloride are shown.
[Table_1]
Why does sulfur dichloride have a lower melting point than sodium chloride?

Diamond and graphite have giant covalent structures of carbon atoms. Which statement describes graphite?

Which row explains the malleability and electrical conductivity of a solid metal? [Table_1]

The equation for the decomposition of ammonium carbonate, \((NH_4)_2CO_3\), is shown. \[(NH_4)_2CO_3(s) \rightarrow 2NH_3(g) + CO_2(g) + H_2O(l)\] \[M_r: \ (NH_4)_2CO_3, \ 96\] The total volume of gas produced is 360 cm\(^3\) at r.t.p. Which mass of ammonium carbonate, \((NH_4)_2CO_3\), is decomposed?

What is the empirical formula of a compound that contains 3.66 g of hydrogen, 37.8 g of phosphorus and 58.5 g of oxygen?

Aqueous copper(II) sulfate is electrolysed using graphite electrodes. Which row identifies the product and observations at each electrode during the electrolysis?

Molten sodium chloride is electrolysed using inert electrodes.
Which row shows the products formed at the cathode and anode?
[Table_1]

The equation for the formation of ammonia is shown. \[ N_2 + 3H_2 \rightarrow 2NH_3 \] The reaction pathway diagram for the reaction is shown. What is the enthalpy change for the reaction?

Sulfur dioxide is converted to sulfur trioxide in the Contact process.
The conditions used are 450 °C and 200 kPa with a vanadium(V) oxide catalyst.
Which row describes and explains the effect of changing conditions on the rate of reaction?
[Table_1]

Hydrogen gas reacts with iodine gas to form hydrogen iodide gas in an equilibrium reaction. $$\text{H}_2(g) + \text{I}_2(g) \iff 2\text{HI}(g) \quad \Delta H = +26.5\text{kJ/mol}$$ Which changes increase the yield of HI at equilibrium?
1. adding a catalyst
2. adding more hydrogen gas
3. increasing the pressure
4. increasing the temperature

The equation for the reaction of carbon with carbon dioxide is shown. $$ \text{C} + \text{CO}_2 \rightarrow 2\text{CO} $$ Which row identifies the carbon atom that is reduced and its change in oxidation number? | | atom that is reduced | change in oxidation number | |------------------|--------------------------|----------------------------| | **A** | carbon in $\text{CO}_2$ | $+2 \rightarrow +4$ | | **B** | carbon in $\text{CO}_2$ | $+4 \rightarrow +2$ | | **C** | elemental carbon, $\text{C}$ | $0 \rightarrow +2$ | | **D** | elemental carbon, $\text{C}$ | $+2 \rightarrow 0$ |

Aqueous iron(II) sulfate is added to acidified potassium manganate(VII). The purple colour of the potassium manganate(VII) disappears.

Aqueous potassium iodide is added to acidified potassium dichromate(VI). A dark brown solution forms.

Which row identifies the role of the iron(II) sulfate and the potassium dichromate(VI) in these reactions?
[Table_1]

Which row shows the difference between a weak acid and a strong acid? [Table_1]

Which substance turns methyl orange red?

Which row describes zinc oxide and calcium oxide? [Table_1]

Which row shows the properties of a transition element? [Table_1]

Fluorine is the element at the top of Group VII of the Periodic Table. Which statement describes fluorine?

When aluminium is placed in dilute hydrochloric acid, there is no reaction.
When zinc is placed in dilute hydrochloric acid, bubbles of gas are immediately given off.
Which statement correctly explains these observations?

Which statements about the use of sacrificial protection to prevent iron from rusting are correct?
1. A more reactive metal than iron is used as a sacrificial protector because it undergoes reduction before iron.
2. Zinc is used as a sacrificial protector because it gains electrons more readily than iron.
3. Copper is not used as a sacrificial protector because it is less reactive than iron.
4. Magnesium is used as a sacrificial protector because it loses electrons more readily than iron.

Aluminium is extracted from its ore by electrolysis. What is the role of cryolite in this process?

Which row identifies two greenhouse gases and three processes by which they contribute to global warming? [Table_1]

Which mixture contains all of the elements in a typical NPK fertiliser?

Bromine reacts with but-2-ene. What is the displayed formula of the product of this reaction?

Which statement is correct?

Which statement explains why ethanoic acid is saturated?

Which statement about compounds in the same homologous series is correct?

Which row shows the properties of methane? [Table_1]

The table shows two methods used to make ethanol. [Table_1]\n\nmethod | type of process | conditions | source of raw material\n-------|----------------|------------|--------------------\n| | temperature /\degree C | pressure / atm | catalyst |\n\n| fermentation | batch | 35 | 1 | yeast | sugar cane\n\n| adding steam to ethene | continuous | 300 | 60 | acid | petroleum\n\nWhich statement gives an advantage of preparing ethanol by fermentation rather than by adding steam to ethene?

Which equation represents an addition reaction?

The structure of part of a polymer is shown: . How many amide and ester linkages are included in the structure shown?

Which structure represents part of a protein?

Which piece of apparatus can only measure a single fixed volume?

Pure solid copper(II) nitrate can be obtained from a mixture of copper(II) nitrate and copper powder.
Three stages in the method are listed.
X add water and stir
Y crystallise
Z filter
After the three stages, the copper(II) nitrate is washed and dried.
What is the correct order of stages X, Y and Z to obtain pure solid copper(II) nitrate from the mixture?

Which row describes a test and the observation for aqueous sulfate ions? [Table_1]