Chemistry Test

I had the hardest chemistry test on Friday. It was on molar mass. I can't believe it, my mind went absolutely blank when the test was in front of me, it asked questions about a given chemical formula and what we can infer from it. The end of the test was worse because it was all written questions that involved conversions like: moles-->moles, moles-->grams and etc. I didn't know the conversions by heart. It really was the hardest test I've had to date.