A container has a volume of #48 L# and holds #12 mol# of gas. If the container is compressed such that its new volume is #15 L#, how many moles of gas must be released to maintain a constant temperature and pressure?

1 Answer
Nov 26, 2016

Answer:

The amount of gas that must be released is #"8.2 mol"#.

Explanation:

This is an example of Avogadro's law, which states that when pressure and temperature are constant, the amount (moles) and volume of a gas are directly proportional, so that if moles increase, so does volume and vice versa.

http://me-mechanicalengineering.com/gas-laws/

Known
#V_1="48 L"#
#n_1="12 mol"#
#V_2="15 L"#

Unknown
#n_2#

Solution
Rearrange the equation to isolate #n_2#. Substitute the known values into the equation and solve.

#n_2=(V_2*n_1)/V_1#

#n_2=(15"L"*12"mol")/(48"L")="3.8 mol"#

Determine how many moles must be removed from the container, subtract #"3.8 mol"# from #"48 mol"#.

#"12 mol"-"3.8 mol"="8.2 mol"#