Oles
A bottle of H3PO4 contains 30.00 g, how many moles are in this container?

Moles in the container : 0.306

Given

30 g of H3PO4

Required

moles in container

Solution

A mole is a unit of many particles (atoms, molecules, ions) where 1 mole is the number of particles contained in a substance that is the same amount as many atoms in 12 gr C-12  

1 mole = 6.02.10²³ particles  

While the number of moles can also be obtained by dividing the mass (in grams) with the molar mass of element or molecule  

MW of H3PO4 = 3.1 + 31 + 4.16 = 98 g/mol

mol = mass : MW

mol = 30 : 98

mol = 0.306