Question in the description can you please explain how you got the answer, thank you.

Question

A gas occupies 40 L of space.  What was the initial volume of the gas at STP when the pressure increases to 800 mmHg and the temperature increases to 350 K. 

Answer 1

STP = 1 atm and 273K

Combined Gas Law:

P1V1/T1 = P2V2/T2

P1 = 1 atm (STP)

V1 = ?

T1 = 273K (STP)

P2 =800 mm Hg x 1 atm/760 mm Hg = 1.05 atm

V2 = 40 L

T2 = 350K

V1 = (1.05)(40)(273) / (1)(350)

V1 = 33 L