We’re being asked to determine the volume of the gas sample collected over water at STP (standard temperature and pressure).
At STP: T = 0°C
P = 1 atm
We’re going to calculate the volume of the gas using the ideal gas equation.
P = pressure, atm
V = volume, L
n = moles, mol
R = gas constant = 0.08206 (L·atm)/(mol·K)
T = temperature, K
The amount of gas (n) will not change and R is a constant:
Relating the two conditions: