A 5.00 L sample of helium at STP expands to 15.0 L. What is the new pressure on the gas?

1 Answer
May 7, 2018

Answer:

#P_2# = 33.3 repeating kPa (kilopascals)

Explanation:

Boyle's Law
#P_1V_1# = #P_2V_2#

Standard Temperature and Pressure:
273.15K with an absolute pressure of 1 atm (up to 1982)
273.15K with an absolute pressure of 100 kPa (1982- present)

(100 kPa)(5.00L) = (#P_2#)(15L)

Divide (100 kPa)(5.00L) by (15L) to isolate for #P_2#.

#(100 * 5)/(15)# = #P_2#

Simplify.

#500/15# = #P_2#

#P_2# = 33.33333333333 kPa

Source(s):
https://www.thoughtco.com/stp-in-chemistry-607533
https://en.wikipedia.org/wiki/Boyle's_law