# What is the molar mass of a compound if 5.19*10^16 molecules of the compound weigh 6.205 microgrammes?

##### 1 Answer

Mar 28, 2015

The molar mass of your compound is

Since molar mass is expressed as the weight of *1 mole* of a compound, you must determine exactly how many moles you've got.

Since 1 mole of a substance contains exactly **Avogadro's number**, you can use this to figure out how many moles you have

Now just divide the weight you were given by the number of moles you have to get the molar mass

**SIDE NOTE** *Notice I've converted micrograms to grams in order to get the molar mass expressed in g/mol.*