A sample of fluorine gas exerts a pressure of 900 mmHg. When the pressure is changed to 1140 mmHg, the volume is 250 mL. What was the original volume?

Let's use Boyle's Law here. P1*V1 = P2*V2

Given: (assuming that there are decimals at the end for Sig Figs)

P1 = 900. mmHg

P2 = 1140. mmHg

V1 = ?

V2 = 250. mL

900. mmHg * ? = 1140. mmHg * 250. mL

? = 1.27*250. mL

? = 318. mL

Therefore, the original volume is 318mL.