Question:
Originally, chemists thought indium oxide had the formula InO. By experiment they showed that 4.8 g of indium combined with 1.0 g of oxygen to produce 5.8 g of indium oxide. The Ar of oxygen was known to be 16. Which value for the Ar of indium is calculated using these data?
A 38 B 77 C 115 D 154
▶️Answer/Explanation
Ans:B
Question
Strontium metal can be extracted from strontium oxide, $\mathrm{SrO}$, by reduction with aluminium. One of the possible reactions is shown.
$
6 \mathrm{SrO}+2 \mathrm{Al} \rightarrow 3 \mathrm{Sr}+\mathrm{Sr}_3 \mathrm{Al}_2 \mathrm{O}_6
$
What is the maximum mass of strontium metal that can be produced from the reduction of $100 \mathrm{~g}$ of strontium oxide using this reaction?
A $41.3 \mathrm{~g}$
B $42.3 \mathrm{~g}$
C $84.6 \mathrm{~g}$
D $169.2 \mathrm{~g}$
▶️Answer/Explanation
Ans:B
Question
In an experiment, $0.600 \mathrm{~mol}$ of chlorine gas, $\mathrm{Cl}_2$, is reacted with an excess of hot aqueous sodium hydroxide. One of the products is $\mathrm{NaClO}_3$.
Which mass of $\mathrm{NaClO}_3$ is formed?
A $21.3 \mathrm{~g}$
B $44.7 \mathrm{~g}$
C $\quad 63.9 \mathrm{~g}$
D $128 \mathrm{~g}$
▶️Answer/Explanation
Ans:A
Question
A sample containing $0.40 \mathrm{~mol}$ of calcium nitrate was decomposed by heating in a roaring Bunsen burner flame until there was no further decomposition.
What are the products of this reaction?
$1 \quad 0.40 \mathrm{~mol}$ of calcium oxide
$20.40 \mathrm{~mol}$ of nitrogen, $\mathrm{N}_2(\mathrm{~g})$
$3 \quad 0.40 \mathrm{~mol}$ of oxygen, $\mathrm{O}_2(\mathrm{~g})$
▶️Answer/Explanation
Ans:D
Question
In a catalytic converter, 5.6 g of carbon monoxide react with an excess of nitrogen monoxide.
What is produced in this reaction?
A 2.4 g of C and 6.0 g of \(NO_2\)
B 2.4 g of C and 9.2 g of \(NO_2\)
C 8.8 g of \(CO_2\) and 1.4 g of \(N_2\)
D 8.8 g of \(CO_2\) and 2.8 g of \(N_2\)
Answer/Explanation
Ans: D
Question
A student reacts 4 mol of ammonia with oxygen to produce an oxide of nitrogen and water only.
Each nitrogen atom increases its oxidation state by 5 in the reaction.
How many moles of oxygen gas react with 4 mol of ammonia in this reaction?
A 4 mol B 5 mol C 7 mol D 10 mol
Answer/Explanation
Ans: B
Question
A 3.0 g sample of \(Na_2CO_3\) powder is stirred into 50 \(cm^3\) of 1.0 mol \(dm^{–3}\) HCl. The volume of \(CO_2\) produced is 600 \(cm^3\)
\(Na_2CO_3(s) + 2HCl(aq) \rightarrow 2NaCl(aq) + CO_2(g) + H_2O(l)\) \([Mr: Na_2CO_3, 106.0]\)
Which volume of \(CO_2\) is produced if 1.0 g of \(Na_2CO_3\) powder is stirred into 50 \(cm^3\) of 1.0 mol \(dm^{–3}\) HCl under the same conditions?
A 600 \(cm^3\)
B 452 \(cm^3\)
C 226 \(cm^3\)
D 200 \(cm^3\)
Answer/Explanation
Ans: C
Question
What is the minimum mass of oxygen required to ensure the complete combustion of 12 dm³ of propane measured under room conditions?
A 60 g B 80 g C 120 g D 160 g
Answer/Explanation
Answer: B
Question
Anhydrous magnesium nitrate, Mg(NO3)2, decomposes when heated, giving a white solid and a mixture of two gases, X and Y. Y is oxygen.
What is the ratio \(\frac{mass of X released}{mass of Y released}\) ?
A \(\frac{1}{0.174}\) B \(\frac{1}{0.267}\) C \(\frac{1}{0.348}\) D \(\frac{1}{3.43}\)
Answer/Explanation
Answer A
Question
A 3.7 g sample of copper(II) carbonate is added to 25 cm3 of 2.0 mol dm–3 hydrochloric acid.
Which volume of gas is produced under room conditions?
A 0.60 dm3 B 0.72 dm3 C 1.20 dm3 D 2.40 dm3
Answer/Explanation
Answer:
A
Question
When calcium nitrate thermally decomposes, oxygen is one of the products.
Which volume of oxygen is produced under room conditions when 0.50 mol of calcium nitrate thermally decomposes?
A 6.0 dm3 B 12.0 dm3 C 18.0 dm3 D 30.0 dm3
Answer/Explanation
Answer:
A
Question
In an experiment, 10 cm3 of an organic compound, J, in the gaseous state is reacted with an excess of oxygen. Steam, 20 cm3 of carbon dioxide and 5 cm3 of nitrogen are the only products.
All gas volumes were measured at the same temperature and pressure.
What could be the identity of J?
1 C2H6N2
2 C2H3N
3 C2H7N
The responses A to D should be selected on the basis of
Answer/Explanation
Answer:
C
Question
Ethanedioic acid, HO2CCO2H, can be oxidised by KMnO4 in dilute sulfuric acid. The products of this reaction are carbon dioxide, water, potassium sulfate and manganese(II) sulfate.
In this reaction each ethanedioic acid molecule loses two electrons as it is oxidised. A half-equation for this process is shown.
HO2CCO2H → 2CO2 + 2H++ 2e–
How many water molecules are produced when five ethanedioic acid molecules are oxidised by KMnO4 in dilute sulfuric acid?
A 5 B 8 C 10 D 16
Answer/Explanation
Answer B
Question
A washing powder contains sodium hydrogencarbonate, NaHCO3, as one of the ingredients. In a titration, a solution containing 1.00 g of this 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?
A 3.0% B 6.0% C 12.0% D 24.0%
Answer/Explanation
Answer C
Question
Which volume of hydrogen, measured under room conditions, is produced when 0.160 g of methanol reacts with an excess of sodium?
A 60 cm3 B 120 cm3 C 240 cm3 D 480 cm3
Answer/Explanation
Answer:
A
Question
A student makes sodium chloride by reacting together 0.025 mol of sodium carbonate with an excess of 0.2 mol \(dm^{–3}\) hydrochloric acid.
\(Na_2CO_3 + 2HCl → 2NaCl + H_2O + CO_2\)
Which statements about the quantities of substance are correct?
1 600 \(cm^3\) of carbon dioxide are produced at room temperature and pressure.
2 250 \(cm^3\) of the hydrochloric acid are needed to exactly neutralise the sodium carbonate.
3 1.46 g of sodium chloride are produced.
The responses A to D should be selected on the basis of
Answer/Explanation
Ans: B
Question
A sample of 2.30 g of ethanol was mixed with an excess of aqueous acidified potassium dichromate(VI). The reaction mixture was then boiled under reflux for one hour. The required organic product was then collected by distillation. The yield of product was 60.0%.
Which mass of product was collected?
A 1.32 g B 1.38 g C 1.80 g D 3.00 g
Answer/Explanation
Ans: C
Question
In this question you should assume methane behaves as an ideal gas. The gas laws can be summarised in the ideal gas equation below.
pV = nRT
The volume of a sample of methane is measured at a temperature of 60 °C and a pressure of 103 kPa. The volume measured is 5.37 × 10–3 m3 .
What is the mass of the sample of methane, given to two significant figures?
A 0.0032 g B 0.018 g C 3.2 g D 18 g
Answer/Explanation
Answer C
Question
5.0 g samples of the carbonates of barium, copper, lithium and magnesium are decomposed tonthe metal oxides and carbon dioxide.
For which compound is there the greatest loss in mass?
A barium carbonate
B copper(II) carbonate
C lithium carbonate
D magnesium carbonate
Answer/Explanation
Answer C
Question
Which fuel would produce the largest mass of CO2 when 10 kg of the fuel undergo complete combustion?
A biodiesel, C17H34O2
B ethanol, C2H6O
C octane, C8H18
D propane, C3H8
Answer/Explanation
Answer C
Question
Sodium hydroxide neutralises acid.
H+ + OH– → H2O
In a 11 000 dm3 sample of an aqueous solution, the concentration of acid, [H+], is 1.26 × 10– 3mol dm–3.
Which mass of solid sodium hydroxide neutralises the acid?
A 0.0214 g B 0.0504 g C 236 g D 554 g
Answer/Explanation
Answer:
D
Question
Which mass of solid residue is obtained from the thermal decomposition of 4.10 g of anhydrous calcium nitrate?
A 0.70 g B 1.00 g C 1.40 g D 2.25 g
Answer/Explanation
Answer:
C
Question
Answer/Explanation
Question
A piece of rock has a mass of 2.00g. It contains calcium carbonate, but no other basic substances. It neutralises exactly 36.0cm3 of 0.500moldm–3 hydrochloric acid.
What is the percentage of calcium carbonate in the 2.00g piece of rock?
A 22.5% B 45.0% C 72.0% D 90.1%
Answer/Explanation
Answer: B
Question
Use of the Data Booklet is relevant to this question.
Which mass of solid residue will be obtained from the thermal decomposition of 4.10g of anhydrous calcium nitrate?
A 0.70g B 1.00g C 1.40g D 2.25g
Answer/Explanation
Ans:C
Question
Use of the Data Booklet is relevant to this question.
1.00g of carbon is combusted in a limited supply of pure oxygen. 0.50g of the carbon combusts to form\( CO_{2}\) and 0.50 g of the carbon combusts to form CO.
The resultant mixture of \(CO_{2}\) and CO is passed through excess NaOH(aq) and the remaining gas is then dried and collected.
What is the volume of the remaining gas? (All gas volumes are measured at 25°C and 1 atmosphere pressure.)
A \(1dm^{3}\) B \(1.5dm^{3}\) C \( 2 dm^{3}\) D\( 3dm^{3}\)
Answer/Explanation
Ans:A
Question
Use of the Data Booklet is relevant to this question.
The compound \(S_{2}O_{7}\) is hydrolysed by water to produce sulfuric acid and oxygen only.
Which volume of oxygen, measured at room temperature and pressure, is evolved when 0.352g of \(S_{2}O_{7}\) is hydrolysed?
A \(12cm^{3}\) B\( 24cm^{3}\) C \( 48cm^{3}\) D \(96cm^{3}\)
Answer/Explanation
Ans:B
Question
Use of the Data Booklet is relevant to this question.
A chemist took\( 2.00dm^{3}\) of nitrogen gas, measured under room conditions, and reacted it with a large volume of hydrogen gas, in order to produce ammonia. Only 15.0% of the nitrogen gas reacted to produce ammonia. What mass of ammonia was formed?
A 0.213g B 0.425g C 1.42g D 2.83g
Answer/Explanation
Ans:B
Question
When equal volumes of saturated solutions of barium hydroxide and calcium hydroxide are mixed, a white precipitate, Y, forms. The mixture is filtered and carbon dioxide is bubbled through the filtrate, producing a second white precipitate, Z.
What are Y and Z?
Answer/Explanation
Ans:C
Question
Use of the Data Booklet is relevant to this question.
Iodine is a black, shiny, non-metallic solid and a member of Group VII. It sublimes easily on heating to give a purple vapour. A sample of iodine vapour of mass 6.35g has a volume of \(1.247dm^{3}\) when maintained at constant temperature and a pressure of\( 1.00 × 10^{5}\)Pa.
If iodine vapour acts as an ideal gas, what is the temperature of the iodine vapour?
A 300K B 600K C 300000K D 600000K
Answer/Explanation
Ans:B
Question
A mixture of \(10cm^3\) of methane and \(10cm^3\) of ethane was sparked with an excess of oxygen.
After cooling to room temperature, the residual gas was passed through aqueous potassium hydroxide.
All gas volumes were measured at the same temperature and pressure.
What volume of gas was absorbed by the alkali?
A 15\(cm^3\) B 20\(cm^3\) C 30\(cm^3\) D 40cm3
Answer/Explanation
Ans: C