Charles’s Law * A sample of water vapor has a volume 25.0 mL at 20 o C and 1.00
ID: 928306 • Letter: C
Question
Charles’s Law
* A sample of water vapor has a volume 25.0 mL at 20oC and 1.00 atm pressure. What is the volume of the vapor at 100oC and 1.00 atm? (Answer: 31.8 mL)
* An aerosol spray can contains a residual gas at 1.05 atm and 20oC. The can is placed in the oven that is set at 325oF. What is the final gas pressure at 325oF? (Assume volume remains constant.)
(Answer: 1.56 atm)
* A sample of helium gas has a volume of 56.0 L at STP. (a) What is the gas volume at -40oC and 216 torr? (b) What is the gas volume at 25oC and 4.0 atm?
(Answer: (a) 168 L; (b) 15.3 L)
Explanation / Answer
V1/T1 = V2/T2
(25/293) = (v2/373)
v2 = 31.826 ml
2.
P1/T1 = P2/T2
(1.05/293.15) = (P2/435.928)
p2 = 1.5614 ATM
3. p1v1/t1 = p2v2/t2
(1*56/273.15) = (((216/760)V2)/(233.15))
V2 = 168.2 L
answer: a) 168 L