Two elements X and Y combine in gaseous state to form XY in the ratio `1:35*5` by mass. The mass of Y that will be required to reat with 2 g of X is

Options

A. `7*1 g`
B. `3*55 g`
C. `71 g`
D. `35*5 g`

Explanation

To solve the problem, we need to determine how much mass of element Y is required to react with 2 grams of element X, given that they combine in a mass ratio of 1:35.5.

### Step-by-Step Solution:

1. **Identify the Mass Ratio**:
The problem states that the elements X and Y combine in a mass ratio of 1:35.5. This means that for every 1 gram of X, 35.5 grams of Y are needed.

2. **Set Up the Proportion**:
We can express the relationship mathematically. If 1 gram of X reacts with 35.5 grams of Y, then we can set up the following proportion for 2 grams of X:
\[ \text{Mass of Y required} = \left(\frac{35.5 \text{ grams of Y}}{1 \text{ gram of X}}\right) \times 2 \text{ grams of X} \]

3. **Calculate the Mass of Y**:
Now, we can calculate the mass of Y required for 2 grams of X:
\[ \text{Mass of Y required} = 35.5 \text{ grams of Y} \times 2 = 71 \text{ grams of Y} \]

4. **Conclusion**:
Therefore, the mass of Y that will be required to react with 2 grams of X is **71 grams**.

### Final Answer:
The mass of Y required to react with 2 grams of X is **71 grams**.

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