Sorry about that. This is from a Junior Science Olympiad paper.

It's not very clear to me why though... if volume : yield = 100% : 6.573 cm^3, then I should find for 35.2% : Volume. However, it still doesn't divide by 35.2. Also everything is in a 1:1 ratio why do I need 100 times more benene?

Yes, I used that formula, I took the total HI concentration as 1.5 because it is the amount we get directly from the graph and didn't square it.

How did you get the reduced mass as m/2.

This is from a College Preliminary test. Apparently requires Advanced Level Chemistry knowledge only.

I see where I went wrong. Thanks!