At 3 atm pressure the volume of gas is 1200ml. what pressure is required to reduce the volume of the gas to 300ml if the temperature remains constant

States that when a gas is held at a constant temperature and mass in a closed container, the volume and pressure vary inversely. The equation to use is P1V1=P2V2.

Given
V1=200mL×1L1000mL=0.2 L
P1=700 mmHg
V2=100mL×1L1000mL=0.1 L

Unknown
P2

Equation
P1V1=P2V2

Solution
Rearrange the equation to isolate P2 and solve.

P2=P1V1V2

P2=(700mmHg×0.2L)0.1L=1400 L, which must be rounded to 1000 L because all of the measurements have only one significant figure.