What is the molar mass of aluminum sulfate?

The molar mass of aluminium sulfate is 342.2 g/mol.

Aluminium sulfate is an with the formula ##Al_2(SO_4)_3##.

It is formed when 2 aluminium cations, ##Al^(3+)##, bond to 3 sulfate anions, ##SO_4^(2-)##.

To get the molar mass of the compound you need to add the molar masses of all the atoms that form the aluminium sulfate formula unit.

This means that you have

• two atoms of aluminium - ##2 * "27.0 g/mol"##
• three atom of sulfur - ##3 * "32.07 g/mol"##
• twelve atoms of oxygen - ##12 * "16.0 g/mol"##

The molar mass of the compound will thus be

##M_M = color(green)("342.2 g/mol")##