# What pressure is required to compress 196.0 liters of air at 1.00 atmosphere into a cylinder whose volume is 26.0 liters?

We use Boyle's law, ${P}_{1} {V}_{1} = {P}_{2} {V}_{2}$. The pressure required for compression is approx. $7.5$ $a t m$
${P}_{2} = \frac{{P}_{1} {V}_{1}}{V} _ 2$ $=$ $\frac{196.0 \cdot L \times 1 \cdot a t m}{26.0 \cdot L}$ $=$ ??atm