1. What volume, in cm3, of 0.200 mol dm–3 HCl(aq) is required to neutralize 25.0 cm3 of 0.
200 mol dm–3
Ba(OH)2(aq)?
A. 12.5
B. 25.0
C. 50.0
D. 75.0
(Total 1 mark)
2. Air bags in cars inflate when sodium azide decomposes to form sodium and nitrogen:
2NaN3(s) → 2Na(s) + 3N2(g)
Calculate the amount, in moles, of nitrogen gas produced by the decomposition of 2.52 mol of NaN3(s).
A. 1.68
B. 2.52
C. 3.78
D. 7.56
(Total 1 mark)
3. What is the coefficient for H2SO4(aq) when the following equation is balanced, using the smallest
possible integers?
__Mg3N2(s) + __H2SO4(aq) → __MgSO4(aq) + __(NH4)2SO4(aq)
A. 1
B. 3
C. 4
D. 7
(Total 1 mark)
4. How many hydrogen atoms are in one mole of ethanol, C2H5OH?
A. 1.00×1023
B. 3.61×1024
C. 5.00
D. 6.00
(Total 1 mark)
1
5. What volume of carbon dioxide, in dm3 under standard conditions, is formed when 7.00 g of ethene
(C2H4, Mr = 28.1) undergoes complete combustion?
A.
B.
C.
D.
(Total 1 mark)
6. Which coefficients would balance this equation?
__ MnO2 + __ HCl → __ MnCl2 + __ Cl2 + __ H2O
MnO2 HCl MnCl2 Cl2 H2O
A. 1 2 1 1 1
B. 1 3 1 1 1
C. 1 4 1 1 2
D. 1 4 1 2 2
(Total 1 mark)
7. The volume of an ideal gas at 27.0 °C is increased from 3.00 dm3 to 6.00 dm3. At what temperature,
in °C, will the gas have the original pressure?
A. 13.5
B. 54.0
C. 327
D. 600
(Total 1 mark)
8. What will be the concentration of sulfate ions in mol dm–3 when 0.20 mol of KAl(SO4)2 is dissolved in
water to give 100 cm3 of aqueous solution?
A. 0.2
B. 1.0
C. 2.0
D. 4.0
(Total 1 mark)
2
9. 4.00 mol of a hydrocarbon with an empirical formula of CH2 has a mass of 280 g. What is the molecular
formula of this compound?
A. C2H4
B. C3H6
C. C4H8
D. C5H10
(Total 1 mark)
10. How many oxygen atoms are there in 0.20 mol of ethanoic acid, CH3COOH?
A. 1.2 × 1023
B. 2.4 × 1023
C. 3.0 × 1024
D. 6.0 × 1024
(Total 1 mark)
11. Which non-metal forms an oxide XO2 with a relative molecular mass of 60?
A. C
B. N
C. Si
D. S
(Total 1 mark)
12. Which sample of nitrogen gas, N2, contains the greatest number of nitrogen molecules?
A. 1.4 g N2
B. 1.4 dm3 of N2 at 1.01 × 105 Pa and 273 K
C. 1.4 × 1023 N2 molecules
D. 1.4 mol N2
(Total 1 mark)
3
13. What volume of sulfur trioxide, in cm3, can be prepared using 40 cm3 sulfur dioxide and 20 cm3 oxygen
gas by the following reaction? Assume all volumes are measured at the same temperature and pressure.
2SO2(g) + O2(g) → 2SO3(g)
A. 20
B. 40
C. 60
D. 80
(Total 1 mark)
14. Which sample has the greatest mass?
A. 6.0 × 1025 molecules of hydrogen
B. 5.0 mol of neon atoms
C. 1.2 × 1024 atoms of silver
D. 1.7 × 102 g of iron
(Total 1 mark)
15. What is the number of oxygen atoms in one mole of CuSO4•5H2O?
A. 5
B. 9
C. 6.0 × 1023
D. 5.4 × 1024
(Total 1 mark)
16. Which statement about solutions is correct?
A. When vitamin D dissolves in fat, vitamin D is the solvent and fat is the solute.
B. In a solution of NaCl in water, NaCl is the solute and water is the solvent.
C. An aqueous solution consists of water dissolved in a solute.
D. The concentration of a solution is the amount of solvent dissolved in 1 dm3 of solution.
(Total 1 mark)
4
17. 5 dm3 of carbon monoxide, CO(g), and 2 dm3 of oxygen, O2(g), at the same temperature and pressure are
mixed together. Assuming complete reaction according to the equation given, what is the maximum
volume of carbon dioxide, CO2(g), in dm3, that can be formed?
2CO(g) + O2(g) → 2CO2
A. 3
B. 4
C. 5
D. 7
(Total 1 mark)
18. What is the maximum mass, in g, of magnesium oxide that can be obtained from the reaction of oxygen
with 2.4 g of magnesium?
A. 2.4
B. 3.0
C. 4.0
D. 5.6
(Total 1 mark)
19. What is the coefficient for O2(g) when the equation for the combustion of 1 mole of pentane is balanced?
C5H12(g) + _O2(g) → _CO2(g) + _H2O(g)
A. 5
B. 6
C. 8
D. 16
(Total 1 mark)
20. Which compound has the empirical formula with the largest mass?
A. C2H6
B. C2H4
C. C2H2
D. C3H6
(Total 1 mark)
5
21. The molar mass of a compound is approximately 56 g mol–1. Which formula is possible for this
compound?
A. NaNO3
B. AgOH
C. MgO
D. KOH
(Total 1 mark)
22. 300 cm3 of water is added to a solution of 200 cm3 of 0.5 mol dm–3 sodium chloride. What is the
concentration of sodium chloride in the new solution?
A. 0.05 mol dm–3
B. 0.1 mol dm–3
C. 0.2 mol dm–3
D. 0.3 mol dm–3
(Total 1 mark)
23. 8.5 g of NH3 are dissolved in H2O to prepare a 500 cm3 solution. Which statements are correct?
I. NH3 is the solute and H2O is the solution
II. The concentration of the solution is 17 g dm–3
III. [NH3] = 1.0 mol dm–3
A. I and II only
B. I and III only
C. II and III only
D. I, II and III
(Total 1 mark)
6
24. The graph below represents the relationship between two variables in a fixed amount of gas.
Which variables could be represented by each axis?
x-axis y-axis
A. pressure temperature
B. volume temperature
C. pressure volume
D. temperature volume
(Total 1 mark)
25. Equal masses of the metals Na, Mg, Ca and Ag are added to separate samples of excess HCl(aq).
Which metal produces the greatest total volume of H2(g)?
A. Na
B. Mg
C. Ca
D. Ag
(Total 1 mark)
26. On analysis, a compound with molar mass 60 g mol–1 was found to contain 12 g of carbon, 2 g of
hydrogen and 16 g of oxygen. What is the molecular formula of the compound?
A. CH2O
B. CH4O
C. C2H4O
D. C2H4O2
(Total 1 mark)
7
27. What is the total number of nitrogen atoms in two mol of NH4NO3?
A. 4
B. 6.02 × 1023
C. 1.20 × 1024
D. 2.41 × 1024
(Total 1 mark)
28. 6.0 mol of aluminium reacts with oxygen to form aluminium oxide. What is the amount of oxygen, in
mol, needed for complete reaction?
4Al(s) + 3O2(g) → 2Al2O3(s)
A. 1.5
B. 3.0
C. 4.5
D. 6.0
(Total 1 mark)
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Topic 1 More Recent Past Paper 2 Questions
1. 0.600 mol of aluminium hydroxide is mixed with 0.600 mol of sulfuric acid, and the following reaction
occurs:
2Al(OH)3(s) + 3H2SO4(aq) → Al2(SO4)3(aq) + 6H2O(l)
(a) Determine the limiting reactant.
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(2)
(b) Calculate the mass of Al2(SO4)3 produced.
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(2)
(c) Determine the amount (in mol) of excess reactant that remains.
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(1)
2. A toxic gas, A, consists of 53.8 % nitrogen and 46.2 % carbon by mass. At 273 K and
1.01×105 Pa, 1.048 g of A occupies 462 cm3. Determine the empirical formula of A.
Calculate the molar mass of the compound and determine its molecular structure.
(Total 3 marks)
9
4. Smog is common in cities throughout the world. One component of smog is PAN (peroxyacylnitrate)
which consists of 20.2 % C, 11.4 % N, 65.9 % O and 2.50 % H by mass.
Determine the empirical formula of PAN, showing your working.
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(Total 3 marks)
5. A student reacted some salicylic acid with excess ethanoic anhydride. Impure solid aspirin was obtained by
filtering the reaction mixture. Pure aspirin was obtained by recrystallization. The following table shows the data
recorded by the student.
Mass of salicylic acid used 3.15 ± 0.02 g
Mass of pure aspirin obtained 2.50 ± 0.02 g
(i) Determine the amount, in mol, of salicylic acid, C6H4(OH)COOH, used.
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(2)
(ii) Calculate the theoretical yield, in g, of aspirin, C6H4(OCOCH3)COOH.
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(2)
10
(iii) Determine the percentage yield of pure aspirin.
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(1)
(iv) State the number of significant figures associated with the mass of pure aspirin obtained, and
calculate the percentage uncertainty associated with this mass.
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(2)
(v) Another student repeated the experiment and obtained an experimental yield of 150 %. The
teacher checked the calculations and found no errors. Comment on the result.
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(1)
(Total 11 marks)
11
