How to do stoichiometry questions

i have an exam tomorrow and i need to now how to do these things. Can someone please do an example and explain step by step plus how to find molar mass.
If you have time can you also tell me
-mole rations
-limiting reagents
-conversion of mass

Thanks.

Molar mass is very simple. You would need a periodic table to find them. Under each element on the periodic table there are multiple digit numbers. (Ex. Oxygen [O] has a molar mass of 15.999, which could be rounded to 16.0). To find the total molar mass, add up all those numbers of each element. Account for the number of particles per element.

Mole Ratios (see links below, videos may be long but will explain everything)
http://www.khanacademy.org/video/the-mole-and-avogadro-s-number?playlist=Chemistry

Stoichiometry Problems:
http://www.khanacademy.org/video/stoichiometry?playlist=Chemistry
http://www.khanacademy.org/video/stoichiometry-example-problem-1?playlist=Chemistry

Limiting Reagents:
http://www.khanacademy.org/video/stoichiometry--limiting-reagent?playlist=Chemistry

SEE OTHER VIDEOS FROM KHANACADEMY (khanacademy.org) for more help.
Good luck!