Question

aluminum has a density of 2.70 g/cm³. if you have a volume of 275 cm³, what is the mass in kilograms? remember to select an answer with the correct number of significant figures.

Explanation:

Step1: Recall density formula

The density formula is $
ho=\frac{m}{V}$, where $
ho$ is density, $m$ is mass, and $V$ is volume. We can re - arrange it to solve for mass: $m =
ho V$.

Step2: Substitute given values

Given $
ho=2.70\ g/cm^{3}$ and $V = 275\ cm^{3}$. So $m=
ho V=2.70\ g/cm^{3}\times275\ cm^{3}=742.5\ g$.

Step3: Convert grams to kilograms

Since $1\ kg = 1000\ g$, then $m = 742.5\ g\times\frac{1\ kg}{1000\ g}=0.7425\ kg$.

Step4: Round to correct significant figures

The density value $2.70$ has three significant figures. Rounding $0.7425\ kg$ to three significant figures gives $0.743\ kg$.

Answer:

$0.743\ kg$