# Practice Problems ```Practice Problems
Chang, Chapter 1
Chemistry: The Study of Change
1.7 Measurement
• A piece of platinum metal with a density of
21.5 g/cm3 has a volume of 4.49 cm3. What is
its mass?
1
1.7 Measurement
• The density of sulfuric acid in a certain car
battery is 1.41 g/ml. Calculate the mass of
242 mL of the liquid.
2
6.4 Enthalpy of Chemical Reactions
• Convert:
a) 327.5&deg;C (the melting point of lead) to degrees Fahrenheit;
b) 172.9&deg;F (the boiling point of ethanol) to degrees Celsius;
c) 77 K, the boiling point of liquid nitrogen, to degrees Celsius.
b) 78.3&deg;C
c) -196&deg;C
3
1.8 Handling Numbers
• Determine the number of significant figures in each of the
following measurements
a)
b)
c)
d)
e)
24 mL
3001 g
0.0320 m3
6.4 x 104 molecules
560 kg
b) 4
c) 3
d) 2
e) 2
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1.8 Handling Numbers
• Carry out the following arithmetic operations &amp;
round off the answers to the appropriate number of
significant figures:
a)
b)
c)
d)
e)
26.5862 L + 0.17 L
9.1 g – 4.682 g
7.1 x 104 dm x 2.2654 x 102 dm
6.54 g &divide; 86.5542 mL
(7.55 x 104 m) – ( 8.62 x 103 m)
b) 4.4 g
c) 1.6 x 107 dm2
d) 0.0756 g/mL
e) 6.69 x 104 m
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1.9 Dimensional Analysis in Solving Problems
• A roll of aluminum foil has a mass of 1.07 kg.
What is its mass in pounds?