Chemistry sample questions Pre IB IGCSE by: F-Rassian
1-Nitrogen reacts with hydrogen to produce ammonia.
N2 + 3H2 → 2NH3
The reaction is exothermic. The bond energies are shown in the table.
What is the energy change for this reaction?
A –1473 kJ / mol
B –87 kJ / mol
C 87 kJ / mol
D 1473 kJ / mol
Answer : A
2-Which change in reaction conditions increases both the collision rate and the proportion of
molecules with sufficient energy to react?
A addition of a catalyst
B increasing the concentration of a reactant
C increasing the surface area of a reactant
D increasing the temperature of the reaction
Answer : D
3-When blue-green crystals of nickel(II) sulfate are heated, water is produced and a yellow solid
remains. When water is added to the yellow solid, the blue-green colour returns.
Which process describes these changes?
A combustion
B corrosion
C neutralisation
D reversible reaction
Answer: D
4-The graph shows how the yield of product in a reversible reaction changes as the temperature and pressure
are changed.
All reactants and products are gases. Which row is correct for this reversible reaction?
5-The positions of elements W, X, Y and Z in the Periodic Table are shown.
Which elements form basic oxides?
A W, X and Y B W and X only C Y only D Z only
6-Ethanoic acid is a weak acid. Hydrochloric acid is a strong acid. Which statements are correct?
1 Ethanoic acid molecules are partially dissociated into ions.
2 1.0 mol / dm3 ethanoic acid has a higher pH than 1.0 mol / dm3 hydrochloric acid.
3 Ethanoic acid is always more dilute than hydrochloric acid.
4 Ethanoic acid is a proton acceptor.
A 1 and 2 B 1 and 3 C 2 and 4 D 3 and 4
7-The properties of an element are shown. Which element has these properties?
8-Three metal compounds, P, Q and R, are heated using a Bunsen burner. The results are shown.
P colourless gas produced, which relights a glowing splint
Q colourless gas produced, which turns limewater milky
R no reaction
Which row shows the identity of P, Q and R?
9- Which changes represent oxidation?
A 1 and 2 B 1 and 3 C 1 only D 2 only
10-A mixture is separated using the apparatus shown.
What is the mixture?
A aqueous copper(II) sulfate and aqueous sodium chloride
B aqueous copper(II) sulfate and copper
C copper and sulfur
D ethanol and ethanoic acid
11-Element X has 7 protons. Element Y has 8 more protons than X.
Which statement about element Y is correct?
A Y has more electron shells than X.
B Y has more electrons in its outer shell than X.
C Y is in a different group of the Periodic Table from X.
D Y is in the same period of the Periodic Table as X.
12-A covalent molecule Q contains only six shared electrons. What is Q?
A ammonia, NH3
B chlorine, Cl 2
C methane, CH4
D water, H2O
13- The arrangement of particles in each of two solids, S and T, are shown. What are S and T?
14-Which statement about metals is correct?
A Metals conduct electricity when molten because negative ions are free to move.
B Metals conduct electricity when solid because positive ions are free to move.
C Metals are malleable because the bonds between the atoms are weak.
D Metals are malleable because the layers of ions can slide over each other.
15-2.56 g of a metal oxide, MO2, is reduced to 1.92 g of the metal, M.
What is the relative atomic mass of M?
A 48 B 96 C 128 D 192
16-When sulfur is heated it undergoes a ......1...... change as it melts.
Further heating causes the sulfur to undergo a ......2...... change and form sulfur dioxide.
Which words complete gaps 1 and 2?
17-Four statements about the effect of increasing temperature on a reaction are shown.
1 The activation energy becomes lower.
2 The particles move faster.
3 There are more collisions between reacting particles per second.
4 There are more collisions which have energy greater than the activation energy.
Which statements are correct?
A 1, 2 and 3 B 1, 3 and 4 C 2, 3 and 4 D 2 and 3 only
18-An example of a redox reaction is shown. Which statement about the reaction is correct?
Zn + Cu2+ 🡪 Zn2+ + Cu
A Zn is the oxidising agent and it oxidises Cu2+.
B Zn is the oxidising agent and it reduces Cu2+.
C Zn is the reducing agent and it oxidises Cu2+.
D Zn is the reducing agent and it reduces Cu2+.
19- Which statement about a reaction in equilibrium is correct?
A Both the forward and the backward reactions are proceeding at the same rate.
B Neither the forward nor the backward reaction is proceeding.
C The amount of product present is no longer affected by changes in temperature or pressure.
D The amount of product present is only affected by a change in pressure.
