How many oxygen atoms are contained in 2.74g of Al2SO42?

Answer 1

Mass of Aluminum Sulfate: 2.74g

Molar Mass of Aluminum Sulfate: 342.14 g/mol

Therefore, number of moles of Oxygen can be calculated by 2.74g * 12/342.14 g/mol = 0.096 moles

Now since u have the moles of Oxygen, the number of oxygen atoms is given by

0.096 mol * (6.02*10^23) particles or atoms/mol

that gives u about 5.78 * 10^22 atoms of oxygen

Answer 2

There are 12 oxygen atoms in 2.74g of Al2(SO4)3.