# Question 7e3cc

Sep 17, 2017

${\text{19 g cm}}^{- 3}$

#### Explanation:

The density of a substance is simply the mass of exactly $1$ unit of volume of that substance.

In your case, a sample of gold is said to have a volume of ${\text{50 cm}}^{3}$. This means that in order to find the density of gold, you must calculate the mass of a ${\text{1-cm}}^{3}$ sample of gold by using the fact that ${\text{50 cm}}^{3}$ of gold have a mass of $\text{965 g}$.

1 color(red)(cancel(color(black)("cm"^3))) * "965 g"/(50color(red)(cancel(color(black)("cm"^3)))) = "19.3 g"

Since this is the mass of ${\text{1 cm}}^{3}$ of gold, you can say that the density of gold is equal to

$\textcolor{\mathrm{da} r k g r e e n}{\underline{\textcolor{b l a c k}{{\text{density = 19 g cm}}^{- 3}}}}$

I'll leave the answer rounded to two sig figs, but keep in mind that you have one significant figure for the volume of the sample.

Notice that this is the same as dividing the mass of the sample by its volume.

${\text{density" = "965 g"/"50 cm"^3 = 965/50 "g"/"cm"^3 ~~ "19 g cm}}^{- 3}$#