# The density of bismuth metal is #9.8# #g##/cm^3#. What is the mass of a sample of bismuth that displaces #65.8# #mL# of water?

##### 1 Answer

#### Answer:

#### Explanation:

Don't be confused by the phrase

... the mass of a sample of bismuth thatdisplaces#"65.8 mL"# of water

that's just a fancy way of saying that you're dealing with a sample of bismuth metal that has a volume of

The idea is that when you add a solid to a sample of water, the **volume** of the solid will be * equal* to the

**volume**of the water it displaces.

Now, the problem provides you with the **density** of bismuth metal, which is said to be equal to

This tells you that **for every cubic centimeter** of bismuth, you get a mass of

#"9.8 g cm"^(-3) = "9.8 g"/"1 cm"^3#

Use the density of the metal as a *conversion factor* to calculate the mass of your sample

#65.8 color(red)(cancel(color(black)("cm"^3))) * "9.8 g"/(1color(red)(cancel(color(black)("cm"^3)))) = "645 g"#

I'll leave the answer rounded to three **sig figs**.