pre test for chemical composion

This test was very hard. I arrived a little late first of all but time wasn't the issue on this test. I had absolutely no clue what this unit was about. I didn't know the main thing in this pre-test. We previously didn't learn on how to convert from moles to mass and mass to moles and the test had like 30 of those questions. The only thing I did on this test was guessing. I knew about the last couple questions as they didn't have to ado much about moles. I have never used moles before so I didn't know what to do with them. A mole is a pretty big number and I have no idea what it represents. I am not looking forward to this unit. I don't like the fact that we have two tough units in a row and that could be terrible for my grade. I actually did surprisingly well on my unit exam for last unit, which was measurement. I think my grade is safe but, not for long...