Explanation
Given
[tex]4Ag+O_2\rightarrow2Ag_2O[/tex]
Mass of Ag2O = 200 g
Required: mass of oxygen
Solution
Step 1: Find the moles of Ag2O
n = m/M where n is the moles, m is the mass and M is the molar mass
n = 200g/231,735 g/mol
n = 0.863 mol
Step 2: Find the mass of oxygen
The molar ratio between Ag2O and O2 is 2:1
Therefore the moles of O2 = 0.863 x 2 = 1.726 mol
Step 3: Calculate the mass of oxygen
m = n x M
m = 1.726 mol x 31.998 g/mol
m = 54.4 g
Answer
Mass of oxygen = 54.4 g
