Answers All exam-style questions and sample answers in this title were written by the authors. In examinations, the way marks are awarded may be different.
Practice question 13
Chapter 1
a 100 000
Practice question 1 a their mass
a 103 b 109
Practice question 14 b 100 000 000
10−3 1 ÷ (10 × 10 × 10)
d s
a cm3 b mm c °C
b 10−10
b 0.0001
a g/cm3 b m/s
Practice question 18
Practice question 5
a (given) b 1 kg e 1 nJ
cm3/s
b 6.7 × 103
c 2.75 × 108
Practice question 7 b 925 000
c 100 600 000
Practice question 8
c 0.000 000 01
c 1 cm3
d 1 ms
0.000 000 01 = 10−8 10−9 m = 1 nm so 10−8 m = 10 nm
Practice question 20 a 1 × 1000 = 1000 mm 14 = 0.014 kg 1000 c 1200 = 1.2 mm 1000 b
1.7 × 107
Practice question 9 b 6.08 × 10−5
c 4.108 × 10−8
Practice question 10 b 0.000 000 722
c 0.005 008
Practice question 21 8 = 0.008 mm 1000
Further questions 80 = 0.32 mg/cm3 250 b i (0.315 + 0.423 + 0.345 + 0.478 + 0.278) = 0.368 s 5 1 a
Practice question 11 1.05 × 10−4 m
Practice question 12 105 10 × 10 × 10 × 10 × 10
c 10−7
Practice question 19
Practice question 6
a 0.0006
ten thousandth
Practice question 17 a 0.1
Practice question 4
one thousandth
Practice question 16 a 10−2
Practice question 3
a 3 × 10−3
0.001
10−4 1 ÷ (10 × 10 × 10 × 10) 0.0001
The numbers would be too small and not very accurate. She should use centimetres or millimetres instead.
a 208
c 10 000 000 000
Practice question 15
b kilograms
Practice question 2
a 5 × 104
c 107
100 000
one hundred thousand
106 10 × 10 × 10 × 10 × 10 × 10 1 000 000 one million
ii 0.368 × 1000 = 0.368 ms c c m3 because the size of the number will not be too big or too small d Caffeine increases reaction times.
1