A flexible container holds #"6.70 mol"# of a gas. An additional #"3.50 mol"# of the gas is added to the container until it reaches a final volume of #"25.4 L"# while temperature and pressure are kept constant, what was the initial volume?
The initial volume was 16.7 L.
This problem requires Avogadro's law, which states that the amount (moles) of a gas is directly proportional to its volume, such that if the amount increases, the volume increases and vice versa. You correctly determined the formula to use:
Rearrange the equation to isolate