Questions 1
Topic-1.1 Particles in the atom and atomic radius
Which species contains a different number of electrons from the other three?
A \(ClO_4^–\)
B \(H_2SO_4\)
C \(SO_4^{2–}\)
D \(Te^{2–}\)
▶️Answer/Explanation
Ans D
Questions 2
Topic-1.4 Ionisation energy
Which factor causes helium to have a higher first ionisation energy than hydrogen?
A In the 1s orbital in helium, electrons are paired.
B The lowest energy level in helium is filled.
C The nuclear charge in helium is higher than in hydrogen.
D There is less shielding of the outer shell in helium.
▶️Answer/Explanation
Ans C
Questions 3
Topic-11.4 The reactions of chlorine
A 0.216 g sample of aluminium carbide reacts with an excess of water to produce methane gas. This is the only carbon-containing product formed in the reaction. This methane gas burns completely in \(O_2\) to form \(H_2O\) and \(CO_2\) only. The volume of \(CO_2\) produced at room temperature and pressure is 108 cm³. What is the formula of aluminium carbide?
A \(Al_2C_3\)
B \(Al_3C_2\)
C \(Al_3C_4\)
D \(Al_4C_3\)
▶️Answer/Explanation
Ans D
Questions 4
Topic-26.2 Homogeneous and heterogeneous catalysts
A reaction between two gases takes place on the surface of the catalytic converter of a petrol-engined car. In this reaction, four reactant molecules produce three product molecules. What could be the two reactant gases in this reaction?
A nitrogen and carbon dioxide
B nitrogen monoxide and carbon dioxide
C nitrogen monoxide and carbon monoxide
D nitrogen dioxide and carbon monoxide
▶️Answer/Explanation
Ans C
Questions 5
Topic-12.1 Nitrogen and sulfur
An ion contains 1 nitrogen atom and 2 hydrogen atoms. It has an H–N–H bond angle of approximately 105°. Which row is correct?
▶️Answer/Explanation
Ans D
Questions 6
Topic-3.6 Intermolecular forces, electronegativity and bond properties
Why does ICl have a higher boiling point than Br₂?
A because of the difference in the bond energies of the covalent bonds within ICl and Br₂
B because of the difference in the polar nature of ICl and Br₂
C because of the difference in the number of electrons contained within ICl and Br₂
D because of the difference in the relative molecular mass of ICl and Br₂
▶️Answer/Explanation
Ans B
Questions 7
Topic-4.1 The gaseous state: ideal and real gases and pV = nRT
In this question you may assume that nitrogen behaves as an ideal gas. One atmosphere pressure = 101 kPa. Which volume does 1.0 g of nitrogen occupy at 50°C and a pressure of 2.0 atmospheres?
A 70 cm³
B 150 cm³
C 470 cm³
D 950 cm³
▶️Answer/Explanation
Ans C
Questions 8
Topic-3.1 Electronegativity and bonding
Which statement about the properties associated with the different types of bonding involved is correct?
A Any covalent compound that contains both oxygen and hydrogen in its molecule forms hydrogen bonds.
B Ionic bonds and covalent bonds cannot both occur in the same compound.
C Ionic compounds differ from metals in that ionic compounds do not conduct electricity in the solid state.
D The only covalent compounds with high melting points are those in which hydrogen bonds occur.
▶️Answer/Explanation
Ans C
Questions 9
Topic- 5.1 Enthalpy change, ΔH
For which reaction is the enthalpy change an enthalpy change of formation?
A \(C(g) + 2H_2(g) \to CH_4(g)\)
B \(\frac{1}{2} N_2(g) + \frac{1}{2} O_2(g) \to NO(g)\)
C \(Na_2O(s) + SO_3(g) \to Na_2SO_4(s)\)
D \(PCl_3(g) + Cl_2(g) \to PCl_5(g)\)
▶️Answer/Explanation
Ans B
Questions 10
Topic- 5.1 Enthalpy change, ΔH
Two standard enthalpy change of formation values are given.
What is the enthalpy change for the reaction \(3VCl_2 \to 2VCl_3 + V\) ?
A \(–210 kJ mol^{–1}\)
B \(–121 kJ mol^{–1}\)
C \(+121 kJ mol^{–1}\)
D \(+210 kJ mol^{–1}\)
▶️Answer/Explanation
Ans D
Questions 11
Topic- 6.1 Redox processes: electron transfer and changes in oxidation number (oxidation state)
Equations for some reactions of hydrogen peroxide are given.
In which reactions is hydrogen peroxide acting as a reducing agent?
A 1 and 3
B 1 only
C 2 and 3
D 2 only
▶️Answer/Explanation
Ans C
Questions 12
Topic-2.3 Formulas
The equation for the reaction of aqueous thiosulfate ions, \(S_2O_3^{2–}\), and aqueous dioxo-vanadium ions, \(VO_2^+\), is shown.
\(2S_2O_3^{2–} + xVO_2^+ + yH^+ \to S_4O_6^{2–} + zVO_2^+ + 2H_2O\)
Which row shows two correct statements about the equation for this reaction?
▶️Answer/Explanation
Ans C
Questions 13
Topic-7.1 Chemical equilibria: reversible reactions, dynamic equilibrium
When some solid Ca₅(PO₄)₃OH is added to a beaker of water, an equilibrium is set up
Which compound, when added to the equilibrium mixture, increases the amount of Ca₅(PO₄)₃OH(s) present?
A \(NH_3\)
B \(NH_4Cl\)
C \(CH_3CO_2H\)
D NaCl
▶️Answer/Explanation
Ans A
Questions 14
Topic-7.1 Chemical equilibria: reversible reactions, dynamic equilibrium
Gaseous hydrogen and gaseous iodine react to form gaseous hydrogen iodide.
\(H_2(g) + I_2(g) \rightleftharpoons 2HI(g)\)
In an experiment, 2.0 mol of hydrogen and 2.0 mol of iodine are placed in a sealed container of volume 1.0 dm³. The Kc value for this reaction under the conditions used is 9.0. How many moles of hydrogen iodide are present at equilibrium?
A 0.57 mol
B 1.2 mol
C 1.5 mol
D 2.4 mol
▶️Answer/Explanation
Ans D
Questions 15
Topic-4.1 The gaseous state: ideal and real gases and pV = nRT
Why does the rate of a gaseous reaction increase when the pressure is increased at a constant temperature?
A More particles have energy that exceeds the activation energy.
B The particles have more space in which to move.
C The particles move faster.
D There are more frequent collisions between particles.
▶️Answer/Explanation
Ans D
Questions 16
Topic-8.2 Effect of temperature on reaction rates and the concept of activation energy
The Boltzmann distribution for a mixture of gases capable of reaction is shown. The two curves represent the mixture of gases at 25°C and at 35°C. The activation energies for the catalysed and uncatalysed reactions are shown
Which row is correct?
▶️Answer/Explanation
Ans D
Questions 17
Topic-9.2 Periodicity of chemical properties of the elements in Period 3
Which oxide is insoluble in aqueous sodium hydroxide?
A MgO
B \(Al_2O_3\)
C \(P_4O_{10}\)
D \(SO_2\)
▶️Answer/Explanation
Ans A
Questions 18
Topic-10.1 Similarities and trends in the properties of the Group 2 metals, magnesium to barium, and their compounds
Sodium and sulfur are burned separately in oxygen. Each reaction has a distinctive coloured flame. Which row is correct?
▶️Answer/Explanation
Ans C
Questions 19
Topic-9.1 Periodicity of physical properties of the elements in Period 3
X and Y are elements in Period 3 of the Periodic Table. Y has a greater atomic number than X. The stable ion formed by Y has a greater radius than the stable ion formed by X. The stable ion formed by Y has 18 electrons. Which row is correct?
▶️Answer/Explanation
Ans A
Questions 20
Topic-10.1 Similarities and trends in the properties of the Group 2 metals, magnesium to barium, and their compounds
X is a Group 2 element in either Period 3 or Period 5. X(OH)₂ is less soluble in water than Ca(OH)₂. When X(NO₃)₂ is heated, it decomposes. Which row is correct?
▶️Answer/Explanation
Ans B
Questions 21
Topic-10.1 Similarities and trends in the properties of the Group 2 metals, magnesium to barium, and their compounds
Which statement comparing magnesium and barium, or their compounds, is correct?
A Magnesium reacts with dilute hydrochloric acid more rapidly than barium does.
B One mole of magnesium carbonate gives off a greater amount of gas when it reacts with an excess of dilute hydrochloric acid than one mole of barium carbonate does.
C The solubility of magnesium sulfate in water is greater than the solubility of barium sulfate in water.
D Magnesium carbonate undergoes thermal decomposition less readily than barium carbonate does.
▶️Answer/Explanation
Ans C
Questions 22
Topic-10.1 Similarities and trends in the properties of the Group 2 metals, magnesium to barium, and their compounds
The colours of the silver halides AgCl, AgBr, and AgI differ. The solubilities of these halides in aqueous ammonia also differ. Which row is correct?
▶️Answer/Explanation
Ans A
Questions 23
Topic-6.1 Redox processes: electron transfer and changes in oxidation number (oxidation state)
The name ‘chlorate’ is used for an anion consisting of chlorine and oxygen only. In a molecule of ICl, the iodine atom has oxidation number x and the chlorine atom has oxidation
number y. When ICl is added to \(H_2O\), iodine is reduced.
\(4ICl + 2H_2O \to 4HCl + O_2 + 2I_2\)
Which statement about the value of x or y is correct?
A x is the same as the oxidation number of Cl in the chlorate ion formed when Cl₂(aq) is added to cold NaOH(aq).
B x is the same as the oxidation number of Cl in the chlorate ion formed when Cl₂(aq) is added to hot NaOH(aq).
C y is the same as the oxidation number of Cl in the chlorate ion formed when Cl₂(aq) is added to cold NaOH(aq).
D y is the same as the oxidation number of Cl in the chlorate ion formed when Cl₂(aq) is added to hot NaOH(aq).
▶️Answer/Explanation
Ans A
Questions 24
Topic- 12.1 Nitrogen and sulfur
Which statement is correct?
A An ammonium ion is basic due to a lone pair of electrons on the nitrogen atom.
B Nitrogen monoxide, NO, reacts with peroxyacetyl nitrate to produce a component of photochemical smog.
C Nitrogen dioxide catalyses the oxidation of atmospheric sulfur dioxide.
D Nitrogen is very unreactive due to the very strong permanent dipole–permanent dipole attractions between the nitrogen atoms.
▶️Answer/Explanation
Ans C
Questions 25
Topic- 13.1 Formulas, functional groups and the naming of organic compounds
The diagram shows the structural formula of a hydrocarbon molecule Q.
How many of the carbon atoms in molecule Q are \(sp^2\) hybridised?
A 3
B 4
C 7
D 10
▶️Answer/Explanation
Ans B
Questions 26
Topic-13.4 Isomerism: structural isomerism and stereoisomerism
Compound X is found in cell walls of some bacteria. Its structural formula is shown.
compound X
\(CH_3(CH_2)_{17}CH=CH(CH_2)_{17}CH(OH)CH(CH_3)CO_2H\)
How many stereoisomers are there with this structural formula?
A 2
B 4
C 6
D 8
▶️Answer/Explanation
Ans D
Questions 27
Topic-13.4 Isomerism: structural isomerism and stereoisomerism
Structural isomerism only should be considered when answering this question. How many straight-chain isomers are there with molecular formula C4H8Cl₂?
A 6
B 7
C 8
D 9
▶️Answer/Explanation
Ans A
Questions 28
Topic-13.2 Characteristic organic reactions
What is true of every nucleophile?
A It attacks a double bond.
B It donates a lone pair of electrons.
C It is a single atom.
D It is negatively charged.
▶️Answer/Explanation
Ans B
Questions 29
Topic-21.1 Organic synthesis
The diagram shows a synthetic route to produce 1-methylcyclohexanol.
What is reagent Y?
A aqueous NaOH
B cold dilute KMnO₄
C ethanolic NaOH
D hot concentrated KMnO₄
▶️Answer/Explanation
Ans A
Questions 30
Topic-21.1 Organic synthesis
X and Y are the reagents required to convert 1-bromopropane into butanoic acid.
What are the correct identities of reagents X and Y?
▶️Answer/Explanation
Ans C
Questions 31
Topic-21.1 Organic synthesis
The table shows three sets of reagents and reaction conditions.
Which sets of reagents and conditions can be used to produce 2-chloro-2-methylpropane as one of the organic products?
A 1, 2 and 3
B 1 and 2 only
C 1 and 3 only
D 2 and 3 only
▶️Answer/Explanation
Ans A
Questions 32
Topic-21.1 Organic synthesis
What are the only structures formed when butan-2-ol is heated with concentrated \(H_2SO_4\)?
▶️Answer/Explanation
Ans B
Questions 33
Topic-21.1 Organic synthesis
The compound ‘leaf alcohol’ is partly responsible for the smell of new-mown grass.
leaf alcohol
CH₃CH₂CH=CHCH₂CH₂OH
What will be formed when ‘leaf alcohol’ is oxidised using an excess of hot acidified K₂Cr₂O₇(aq)?
A CH₃CH₂CH(OH)CH(OH)CH₂CO₂H
B CH₃CH₂COCOCH₂CO₂H
C CH₃CH₂CH=CHCH₂CO₂H
D \(CH_3CH_2CO_2H\) and \(HO_2CCH_2CO_2H\)
▶️Answer/Explanation
Ans C
Questions 34
Topic- 21.1 Organic synthesis
Compound X:
● does not react with Tollens’ reagent
● forms a yellow precipitate with alkaline \(I_2\)(aq)
● does not react with sodium.
What could be the identity of X?
A \(CH_3CHO\)
B \(C_2H_5COCH_3\)
C CH₃COOC₂H₅
D \(CH_3CHOHCH_3\)
▶️Answer/Explanation
Ans B
Questions 35
Topic- 13.2 Characteristic organic reactions
Which compound can undergo nucleophilic addition?
A bromoethane, \(C_2H_5Br\)
B ethanal, CH₃CHO
C ethane, \(C_2H_6\)
D ethene, \(C_2H_4\)
▶️Answer/Explanation
Ans B
Questions 36
Topic- 13.2 Characteristic organic reactions
C₂H₅COOCH₃ is reacted with aqueous acid. The products from this reaction are reacted with LiAlH₄ to form two molecules Y and Z. What are the identities of molecules Y and Z?
A both molecules are C₂H₅OH
B CH₃OH and CH₃CHOHCH₃
C CH₃OH and C₂H₅OH
D CH₃OH and C₂H₅CH₂OH
▶️Answer/Explanation
Ans D
Questions 37
Topic-4.1 The gaseous state: ideal and real gases and pV = nRT
A sample of propanoic acid of mass 3.70 g reacts with an excess of magnesium. A second sample of propanoic acid of mass 3.70 g reacts with an excess of sodium. Both reactions go to completion forming a gas. Which row is correct?
▶️Answer/Explanation
Ans A
Questions 38
Topic-13.2 Characteristic organic reactions
Which statement about \(H_2C=C(CH_3)CH_2CO_2CH_3\) is correct?
A It can be hydrolysed to a secondary alcohol.
B It can be made using ethanoic acid and a suitable alcohol.
C It gives a positive test with alkaline \(I_2\)(aq).
D When treated with hot concentrated acidified KMnO₄, it gives CH₃COCH₂COOH as one product.
▶️Answer/Explanation
Ans D
Questions 39
Topic- 20.1 Addition polymerisation
Synthetic resins can be made by polymerisation of a variety of monomers including prop-2-en-1-ol, CH₂=CHCH₂OH. Which structure represents the repeat unit in the polymer poly(prop-2-en-1-ol)?
▶️Answer/Explanation
Ans B
Questions 40
Topic-22.2 Mass spectrometry
Vitamin C has the structure shown.
The mass spectrum of vitamin C has a molecular ion peak with an m/e value of 176 and a relative abundance of 7.0%. What is the abundance of the M +1 peak?
A 0.462%
B 0.539%
C 0.616%
D 0.693%
▶️Answer/Explanation
Ans A