Answer:
0.690 g/mL
Explanation:
Density is the ratio of mass to volume:
gasoline mass = (flask+gas mass) - (flask mass) = 145.028 g -110.525 g
gasoline mass = 34.503 g
Density = (gas mass)/(gas volume) = (34.503 g)/(50.0 mL)
Density = 0.690 g/mL
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The least-precise number in this calculation is the sample volume, which has 3 significant figures. Thus, the answer is good only to 3 significant figures.