A container has a volume of #3 L# and holds #18 mol# of gas. If the container is expanded such that its new volume is #6 L#, how many moles of gas must be injected into the container to maintain a constant temperature and pressure?

1 Answer
Dec 18, 2016

#36 "moles"#

Explanation:

Let's use Avogadro's law:

#v_1/n_1 = v_2/n_2#

The number 1 represents the initial conditions and the number 2 represents the final conditions.

• Identify your known and unknown variables:

#color(purple)("Knowns:"#
#v_1#= 3 L
#v_2#= 6 L
#n_1#= 18 mol

#color(magenta) ("Unknowns:"#
#n_2#

• Rearrange the equation to solve for the final number of moles:

#n_2=(v_2xxn_1)/v_1#

• Plug in your known values to obtain the final number of moles:

#n_2=(6cancelLxx18mol)/(3\cancel"L")# = # 36 mol#