posted by Anonymous .
A reaction of 1 L of chlorine gas (Cl2) with 3 liters of fluorine gas (F2) yields 2 liters of a gaseous product. All gas volumes are at the same temperature and pressure. What is the formula of the gaseous product?
So it would look roughly like this?
Cl2 + F2 --> 2ClF ?
When all are gases, we can dispense with moles; L are proportional.
From your rough equation, we have
Cl2 + F2 ==> xClF
1 L Cl2 reacts with 3 L F2 to produce 2 L product. So the coefficient for Cl2 is 1, coefficient for F2 is 3 and the coefficient for ClF is 2. Now we have
Cl2 + 3F2 ==>2ClFx
and x must be 3.