In stoichiometry, what is molar mass used for?

1 Answer

In stoichiometry, molar mass is used to convert between the mass of a substance and how many moles of a substance.

Explanation:

For example: The molar mass of water is 18g/mol
Q: How many moles are there in a 4.5g sample of water?

#(4.5g H_2O)/1 x (1 mol H_2O)/(18g H_2O)# = 0.25 mol #H_2O#

In both of the videos below, molar mass is used to convert between mass (g) and mole amounts of chemical substances.


Video from: Noel Pauller


Video from: Noel Pauller

Hope this helps!