**calculate the volume occupied by 18g of water vapor at 100c and 1 atm**

**Answer:**

For this problem, the gas law formula

PV=nRT must be used where P is pressure, V is volume, n=number of moles, R=gas constant and T is temperature.

Since volume is asked, rearrange the formula so it will become

V=nRT/P .

R=0.08205 L-atm/K-mol so convert the 18g to mole and 100c to Kelvin first.

18g/(2.02+16)g/mol=1mol and 100celsius+273K=373Kelvinâ€¦substituting it to the formula,

V=((1mole water)0.08205x(373K))/1atm=30.60465L