The composition of compound A is `40%` X and `60%Y`. The composition of compound B is `25%` X and `75%Y`. According to the law of multiple Proportions the ratio of the weight of element Y in compounds A and B is

Options

A. `1:2`
B. `2:1`
C. `2:3`
D. `3:4`

Explanation

To solve the problem, we need to find the ratio of the weight of element Y in compounds A and B using the given percentages. Here’s a step-by-step breakdown of the solution:

### Step 1: Determine the composition of compounds A and B
- **Compound A**:
- X = 40%
- Y = 60%

- **Compound B**:
- X = 25%
- Y = 75%

### Step 2: Assume a common total mass for both compounds
To make calculations easier, assume a total mass of 100 grams for each compound. This allows us to directly convert percentages to grams.

- For **Compound A**:
- Mass of X = 40% of 100g = 40g
- Mass of Y = 60% of 100g = 60g

- For **Compound B**:
- Mass of X = 25% of 100g = 25g
- Mass of Y = 75% of 100g = 75g

### Step 3: Find the ratio of the mass of Y in both compounds
Now we need to find the ratio of the mass of Y in compounds A and B.

- Mass of Y in Compound A = 60g
- Mass of Y in Compound B = 75g

### Step 4: Calculate the ratio
The ratio of the mass of Y in compound A to the mass of Y in compound B is:

\[ \text{Ratio of Y in A to Y in B} = \frac{\text{Mass of Y in A}}{\text{Mass of Y in B}} = \frac{60g}{75g} \]

### Step 5: Simplify the ratio
To simplify the ratio:

\[ \frac{60}{75} = \frac{60 \div 15}{75 \div 15} = \frac{4}{5} \]

Thus, the ratio of the weight of element Y in compounds A and B is \(4:5\).

### Final Answer
The ratio of the weight of element Y in compounds A and B is \(4:5\).

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