Q1. Which aqueous solution contains the greatest number of ions?
A
200 cm3 of 1.5 mol dm−3 MgCl2
B
400 cm3 of 0.8 mol dm−3 MgSO4
C
500 cm3 of 1.0 mol dm−3 NaCl
D
1000 cm3 of 0.25 mol dm−3 Na2SO4
Q2. The maximum permitted concentration of sulfur in diesel fuel is 10 mg of sulfur in
1 kg of diesel fuel.
(a) What is this concentration of sulfur in ppm?
(1)
A
0.00001
B
0.01
C
10
D
10 000
(b) 3.2 kg of this diesel fuel is burned in air.
What is the maximum volume, in dm3, of sulfur dioxide which can be produced,
measured at room temperature and pressure (r.t.p.)?
[Molar volume of a gas at r.t.p. = 24 dm3 mol−1]
(1)
A
0.024
B
0.77
C
2.4
D
24
Q3. A mass of 0.23 g of sodium was added to 350 cm3 water to form hydrogen and a
solution of sodium hydroxide.
Na(s) + H2O(l) → NaOH(aq) + 1⁄2H2(g)
(a) What is the concentration, in mol dm−3, of sodium hydroxide in the solution
formed?
(1)
A
0.010
B
0.029
C
0.29
D
0.66
(b) What is the maximum volume, in cm3, of hydrogen which could be formed,
measured at r.t.p.?
[Molar volume of a gas at r.t.p. = 24 dm3 mol−1]
(1)
A
120
B
240
C
480
D
2800
(d) Sodium hydroxide solution was added to magnesium sulfate solution.
The equation for the reaction is shown.
2NaOH(aq) + MgSO4(aq) → Mg(OH)2(s) + Na2SO4(aq)
What is the atom economy (by mass) for the production of magnesium hydroxide?
[Ar values: H = 1.0 O = 16.0 Na = 23.0 Mg = 24.3 S = 32.1]
(1)
A
29.1 %
B
41.0 %
C
48.4 %
D
50.0 %
Q4. Iron(III) oxide is reduced by hydrogen in a two-step process.
Step 1: 3Fe2O3 + H2 → 2Fe3O4 + H2O
Step 2: Fe3O4 + 4H2 → 3Fe + 4H2O
What is the maximum mass of iron that could be produced from 39.9 tonnes of Fe2O3
?
[Ar values: H = 1.0 O = 16.0 Fe = 55.8]
A
6.98 tonnes
B
13.95 tonnes
C
27.90 tonnes
D
41.85 tonnes
Q5. A solution of sodium chloride, NaCl, is prepared by dissolving 10.0 g of the solid
in distilled water and making the solution up to 250.0 cm3.
What is the concentration of the solution, in mol dm−3 ?
[Mr NaCl = 58.5]
A
0.171
B
0.684
C
10.0
D
40.0
Q6. What is the concentration, in mol dm−3, of a solution containing 7.84 g of
phosphoric(V) acid, H3PO4, in 400 cm3 of solution?
(1)
A
0.02
B
0.08
C
0.20
D
19.6
Q7. Which aqueous solution has the highest concentration, in mol dm-3, of chloride
ions?
A
0.1 g dm-3 HCl
B
0.1 g dm-3 NaCl
C
0.1 g dm-3 KCl
D
0.1 g dm-3 BaCl2
Q10. Which of these gases occupies 6.0 dm3 at room temperature and pressure
(r.t.p.)?
[molar volume of gas at r.t.p. = 24.0 dm3 mol−1
Ar values: He = 4.0 C = 12.0 N = 14.0 O = 16.0]
A
2.0 g of helium
B
4.0 g of oxygen
C
11.0 g of carbon dioxide
D
14.0 g of nitrogen
Q11. What mass of anhydrous sodium carbonate is needed to make 50.0 cm3 of a
0.0800 mol dm–3 solution of sodium carbonate, Na2CO3?
[Ar values: C = 12.0, O = 16.0, Na = 23.0]
A
0.332 g
B
0.424 g
C
5.30 g
D
8.48 g
Q12. What is the maximum volume of hydrogen formed, at room temperature and
pressure (r.t.p.), when 0.207 g of lithium is added to excess water?
2Li(s) + 2H2O(l) → 2LiOH(aq) + H2(g)
[Ar Li = 6.9
Molar volume of gas at r.t.p. = 24.0 dm3 mol–1]
A
0.36 dm3
B
0.72 dm3
C
1.44 dm3
D
2.48 dm3
Q13. Which of these solutions contains the greatest number of ions?
A
20.0 cm3 of 0.5 mol dm−3 KCl
B
0.40 dm3 of 0.03 mol dm−3 KCl
C
10.0 cm3 of 0.6 mol dm−3 CaCl2
D
0.15 dm3 of 0.04 mol dm−3 CaCl2
Q15. A 0.210 g sample of a volatile organic liquid C is injected into a gas syringe and
heated in an oven.
At 100 kPa and 358 K, the syringe contains 72.5 cm3 of gas.
(a) Calculate the molar mass of C.
[pV = nRT
R = 8.31 J mol−1 K−1]
Q17. Which pair of substances contains the same number of moles at room
temperature and pressure (r.t.p.)?
[Ar values Ca = 40, Li = 7, Al = 27, Mg = 24. Molar volume of gas at r.t.p. = 24 dm3
mol−1]
(1)
3
A
24 dm of chlorine, Cl2, and 20 g of calcium, Ca
B
24 dm3 of oxygen, O2, and 14 g of lithium, Li
C
1.2 dm3 of hydrogen, H2, and 2.7 g of aluminium, Al
D
1.2 dm3 of nitrogen, N2, and 1.2 g of magnesium, Mg
Q18. Propane burns completely in oxygen as shown.
C3H8(g) + 5O2(g) → 3CO2(g) + 4H2O(l)
100 cm3 of propane was mixed with 600 cm3 of oxygen and the mixture was ignited.
What is the total volume, in cm3, of the gas mixture at the end of the reaction?
All gas volumes were measured at room temperature and pressure.
A
300
B
400
C
700
D
800