Question

Oxygen was first isolated by the decomposition of mercuric oxide (hgo) into mercury and oxygen, if 58.67g of mercuric oxide were completely decomposed to generate 54.34g of mercury how many grams of oxygen should have been produced

Answer 1

This is a decomposition reaction, where the balanced formula is

2HgO = 2Hg + O2

1) First, we need to convert 8 grams of oxygen to mols.

8 grams O2 • 32 grams O2 = 0.25 mols O2

2) Now we can use the mole ration of our balanced equation to calculate how many mols of HgO we need to produce 0.25 mols of O2

0.25 mols O2 • 2 mols HgO = 0.5 mols HgO

3) Lastly, we need to convert 0.5 mols HgO to grams of HgO

0.5 mols HgO • 216.59 grams HgO = 108.295 grams HgO needed to produce 8 grams of O2.