Question #66b6c
1 Answer
Explanation:
To solve this, we can use the quantityvolume relationship of gases.
According to Avogadro's hypothesis:
The number of moles of a gas is directly to proportional to the volume the gas occupies.
And, under constant temperature and pressure conditions, we get the equation
Our known quantities are:

#V_1# :#8.15# #"L"# 
#n_1# :#9.51# #"mol"# 
#V_2# :#18.3# #"L"#
We can plug these into the equation and solve for the final quantity,
We're asked to find the number of moles needed to be added: so we subtract the initial amount from the final amount: