Question

Magnesium Oxide decomposes to produce 3.54 grams of oxygen gas. How many grams of magnesium oxide decomposed?

Answer 1

Let us solve for it

Explanation:

Magnesium oxide

• It is MgO  
• Its molecular mass is : 24 +16=40 g
• When MgO decomposes it forms = 3.54 g of oxygen gas  
• when 40 g of MgO decomposes it forms = 16g of oxygen  
• or we can say that :
• 16g of oxygen is produced when 40 g of MgO is decomposed .
• 1g of oxygen will be formed from =40/16g of MgO  
• 3.54 g of oxygen will be formed = 40/16 x 3.54 =8.85g of MgO