Which law states that if two elements can coombine to form more than one compound the masses of one element that combine with a fixed mass of other element are in the ratio of small whole numbers?

Options

A. Avagadro law
B. Law of definite composition
C. Law of multiple proportions
D. Gay Lussac's law of gaseous volumes

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks about a specific law in chemistry that relates to the combination of two elements to form multiple compounds.

2. **Identifying the Law:**
The law that describes this phenomenon is known as the **Law of Multiple Proportions**. This law states that when two elements can combine to form more than one compound, the masses of one element that combine with a fixed mass of the other element are in the ratio of small whole numbers.

3. **Explanation of the Law:**
- When two elements (let's say A and B) combine, they can form different compounds (like AB and AB2).
- According to the law, if we take a fixed mass of element B, the masses of element A that combine with this fixed mass will be in a simple whole number ratio.
- For example, consider carbon (C) and oxygen (O). Carbon can combine with oxygen to form carbon monoxide (CO) and carbon dioxide (CO2).
- If we take a fixed mass of oxygen (for instance, 16 grams), we can find that the mass of carbon that combines with it to form CO is 12 grams, and to form CO2 is 24 grams. The ratio of these masses (12:24) simplifies to 1:2, which is a small whole number.

4. **Conclusion:**
Therefore, the law that states that if two elements can combine to form more than one compound, the masses of one element that combine with a fixed mass of the other element are in the ratio of small whole numbers is the **Law of Multiple Proportions**.

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