Which of the following changes decreases the pressure in a gaseous system?

a) decreasing the volume

b) increasing the temperature

c) increasing the number of gas molecules

d) all of the above

e) none of the above

The correct option is: e) none of the above

Explanation:

According to the ideal gas equation: PV = nRT, here, V - volume, P-pressure T - temperature, n - number of moles of the gas and R - the ideal gas constant.

Therefore, the factors affecting the pressure of the gas are: volume, temperature and the number of moles of gas.

a) If temperature and the number of moles of gas is constant and the volume decreases, then the pressure of the gas increases. This is because according to the ideal gas equation, pressure and volume are inversely proportional to each other.

b) If volume and the number of moles of gas is constant and the temperature increases, then the pressure of the gas also increases. This is because according to the ideal gas equation, pressure and temperature are directly proportional to each other.

c) If volume and temperature is constant and the number of moles of gas increases, then the pressure of the gas also increases. This is because according to the ideal gas equation, pressure and the number of moles of gas are directly proportional to each other.