Answer:
To find the volume of the gas at a pressure of 0.40 atm if the temperature is held constant, we can use the ideal gas law:
PV = nRT
Where P is the pressure of the gas, V is the volume of the gas, n is the number of moles of gas, R is the ideal gas constant, and T is the temperature of the gas.
Since the number of moles and the temperature of the gas are constant, we can rearrange the equation to solve for V:
V = (nRT)/P
Plugging in the given values, we have:
V = (nRT)/P = (nRT)/(0.40 atm)
We know that the original volume of the gas was 0.50 L, so the new volume will be:
V = (0.50 L)(0.20 atm)/(0.40 atm) = 0.50 L / 2 = 0.25 L
So the volume of the gas at a pressure of 0.40 atm will be 0.25 L. The correct answer is A) 0.25 L.