Question

question 10 of 30
what is the mass of 2.7 l of water?
a. 270 μg
b. 270 mg
c. 2.7 kg
d. 2.7 g

Explanation:

Step1: Recall density formula

The density formula is $
ho=\frac{m}{V}$, where $
ho$ is density, $m$ is mass and $V$ is volume. The density of water is $
ho = 1000\ kg/m^{3}$ or $1\ g/cm^{3}$. First, convert the volume of water to $cm^{3}$. Since $1\ L=1000\ cm^{3}$, then $V = 2.7\ L=2.7\times1000\ cm^{3}=2700\ cm^{3}$.

Step2: Rearrange density formula for mass

From $
ho=\frac{m}{V}$, we can get $m =
ho V$. Substitute $
ho = 1\ g/cm^{3}$ and $V = 2700\ cm^{3}$ into the formula. So $m=1\ g/cm^{3}\times2700\ cm^{3}=2700\ g$. Convert $2700\ g$ to $kg$, since $1\ kg = 1000\ g$, then $m=\frac{2700}{1000}\ kg = 2.7\ kg$.

Answer:

C. 2.7 kg