A compound consists of 40% sulfur and 60% oxygen by mass. In a sample of the same compound. Class 9

A compound consists of 40% sulfur and 60% oxygen by mass. In a sample of the same compound. Class 9

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Question 1.

A compound consists of 40% sulfur and 60% oxygen by mass. In a sample of the same compound containing 20 g of sulfur, what mass of oxygen must be present to satisfy the Law of Constant Proportions? Class 9

Answer:

The compound has sulfur and oxygen in the mass ratio of 40:60 = 2:3. If 20 g of sulfur is present, then: Mass of oxygen = (60/40) × 20 = 30 g.

Therefore, 30 g of oxygen must be present.

Question 2.

Carbon monoxide (CO) contains carbon and oxygen in the mass ratio of 3:4. How much oxygen will combine with 9 g of carbon to form carbon monoxide? Class 9

Answer:

Carbon and oxygen are in the mass ratio 3:4. If 3 g of carbon combines with 4 g of oxygen, then 9 g of carbon will combine with = (4/3) × 9 = 12 g of oxygen.

Therefore, 12 g of oxygen will combine with 9 g of carbon to form carbon monoxide.