2.A flask and stopper have a mass of 110.525 g. A 50.0-mL sample of gasoline is transferred to the flask, and the flask, stopper, and liquid have a mass of 145.028 g. Find the density of gasoline in g/mL. Show work and report density with the appropriate number of significant figures.

  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

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.

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