A container has a volume of #24 L# and holds #9 mol# of gas. If the container is expanded such that its new volume is #36 L#, how many moles of gas must be injected into the container to maintain a constant temperature and pressure?
1 Answer
Explanation:
We're asked to find the number of moles that need to be added to a container so that the temperature and pressure remain constant.
To do this, we can use the quantityvolume relationship of gases, illustrated by Avogadro's law:
#(n_1)/(V_1) = (n_2)/(V_2)color(white)(al)# (constant temperature and pressure)
Our quantities:

#n_1 = 9# #"mol"# 
#V_1 = 24# #"L"# 
#n_2 = ?# 
#V_2 = 36# #"L"#
Plugging in known values, and solving for the final quantity (
This represents the final quantity of moles of gas; to find the amount that needs added, we subtract the initial value from the final value: