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 yahoo

Answer 1

Answer : 4.3328 grams of oxygen produced.

Solution : Given,

Mass of HgO = 58.67 g

Mass of Mercury = 54.34 g

Molar mass of HgO = 216.59 g/mole

Molar mass of Oxygen = 32 g/mole

First we have to calculate the moles of HgO.

$\text{ Moles of }HgO=\frac{\text{ Given mass of }HgO}{\text{ Molar mass of }HgO}=\frac{58.67g}{216.59g/mole}=0.2708moles$

The moles of HgO = 0.2708 moles

The decomposition reaction of HgO is,

$2HgO\rightarrow 2Hg+O_2$

From the reaction, we conclude that

2 moles of HgO produces 1 mole of oxygen

0.2708 moles of HgO produces $\frac{1mole}{2moles}\times 0.2708moles=0.1354moles$ of oxygen

The moles of oxygen = 0.1354 moles

Now we have to calculate the mass of oxygen produces.

Mass of oxygen = Moles of oxygen × Molar mass of oxygen

Mass of oxygen = 0.1354 moles × 32 g/mole = 4.3328 grams

Therefore, 4.3328 grams of oxygen produced.