ANSWERS TO TEST YOURSELF QUESTIONS 1 1CHEMISTRY FOR THE IB DIPLOMA © CAMBRIDGE UNIVERSITY PRESS 2011

Answers to test yourself questions 9 a 2.00 g b 1.67 g c 2.29 g

10 CO2 CH HO C3H8 H2O PCl5 C6H5CH3

11Empirical

formula

Relative

molecular mass

Molecular

formula

HO 34.02 H2O2

ClO3 166.90 Cl2O6

CH2 84.18 C6H12

BNH2 80.52 B3N3H6

12 a CH3 b C2H6

13 Cl2O

14 I2O5

15 C4H10O

16 Fe2O3

17 C3H8

18 C2H5

19 C3H8O

20 a 2NO + O2 → 2NO2

b C3H8 + 5O2 → 3CO2 + 4H2O c CaCO3 + 2HCl → CaCl2 + CO2 + H2O d C2H5OH + 3O2 → 2CO2 + 3H2O e WO3 + 3H2 → W + 3H2O f 2H2O2 → O2 + 2H2O g 4CrO3 → 2Cr2O3 + 3O2

h Al4C3 + 6H2O → 3CH4 + 2Al2O3

i 8HI + H2SO4 → H2S + 4H2O + 4I2

j 4PH3 + 8O2 → P4O10 + 6H2O

21 a 0.2 mol b 0.05 mol c 0.01 mol d 0.9 mol e 0.6 mol f 3.6 × 10−3 mol

22 a 0.363 g b 2.67 g c 4.62 g d 2.97 g

23 a 80.0% b 94.7% c 65.1%

Chapter 11

Compound Relative molecular mass

SO2 64.06

NH3 17.04

C2H5OH 46.08

MgCl2 95.21

Ca(NO3)2 164.10

CH3(CH2)5CH3 100.23

PCl5 208.22

Mg3(PO4)2 214.25

Na2S2O3 158.10

CH3CH2CH2COOCH2CH3 116.18

2Compound Molar mass /

g mol−1

Mass / g Number of

moles / mol

H2O 18.02 9.01 0.500

CO2 44.01 5.00 0.114

H2S 34.08 3.41 0.100

NH3 17.04 59.6 3.50

Q 28.6 1.00 0.035 0

Z 51.6 0.0578 1.12 × 10−3

Mg(NO3)2 148.33 1.75 0.0118

C3H7OH 60.11 2500 41.6

Fe2O3 159.7 9.07 × 10−3 5.68 × 10−5

3 a 2.99 × 10−23 g b 2.83 × 10−23 g c 7.31 × 10−23 g

4 a 1.20 × 1024 b 4.82 × 1023

c 9.03 × 1022

5 a 2.41 × 1022

b 9.63 × 1023

c 5.42 × 1024

6 a 0.8 mol b 0.7 mol c 0.12 mol

7 a 34.72% b 43.19% c 61.24%

8 a 1.60 g b 2.50 g c 5.64 g

2 CHEMISTRY FOR THE IB DIPLOMA © CAMBRIDGE UNIVERSITY PRESS 2011ANSWERS TO TEST YOURSELF QUESTIONS 1

24 a H2SO4

b H2O c HNO3

d NaCl

25 0.15 g

26 3.10 tonnes

27 a 200 cm3 b 1.6 dm3

28 a 0.0107 molb 0.0893 molc 4.46 × 10−3 mol

d 0.017 86 mole 0.011 16 mol

29 a 2.24 dm3

b 2240 dm3

c 6.05 dm3

d 19.04 dm3

e 13.4 dm3

30 108 cm3

31 1890 cm3

32 0.4732 g

33 a 290 cm3

b 300 cm3

34 21.7 cm3

35 196 °C

36 0.0655 mol

37 43.2 g mol−1

38 28.2 dm3

39 a 0.112 dm3

b 560 cm3

40 0.782 g

41 a 3.55 gb 0.200 mol dm−3

42 a 4.40 × 10−3 molb 2.34 × 10−3 mol

c 0.0108 mol

43 0.475 mol dm−3

44 a 1.25 gb 0.280 dm3

45 42.8 cm3

46 56.0 cm3