# When a gas in a container is compressed to half its volume, what happens to its density?

$I n i t i a l D e n s i t y = \frac{m a s s}{V o l u m e} = \frac{m}{V}$
and Volume is cut in half = $\frac{V}{2}$ => $N e w D e n s i t y$ = $\frac{m a s s}{\frac{V}{2}}$ = $2 \left(\frac{m}{V}\right)$ = $2 \left(I n i t i a l D e n s i t y\right)$