How do I do this ?? Please be detailed

Question

A compound made of two elements, iridium (Ir and oxygen (O), was produced in a lab by hitting iridium Wall exposed to air. The following data was collected:

mass of crucible: 38.26 g

mass of crucible and iridium : 39.52 g

mass of crucible and iridium oxide : 39.73 g

a) determine the empirical formula

Answer 1

To get the mass of the compound, we subtract the mass of the crucible from the total mass:

39.73 g - 38.26 g = 1.47 g of iridium oxide

To get the mass of iridium, we subtract the mass of the crucible from that of the crucible + iridium:

39.52 g - 38.26 g = 1.26 g of iridium

To get the mass of oxygen, we subtract the mass of iridium from that of iridium oxide:

1.47 g - 1.26 g = 0.21 g oxygen

Now, we convert grams to moles:

iridium: 1.26 g Ir x 1 mol Ir/192 g = 0.00656 moles Ir

oxygen: 0.21 g O x 1 mol/16 g = 0.0131 moles O

Divide through by the lowest value (0.00656) to get...

0.00656 mol Ir/0.00656 = 1.0 mol Ir

0.0131 mol O/0.00656 = 2.0 mol O

Empirical formula = IrO₂

Answer 2