`15` grams of methyl alcohol is dissolved in `35` grams of water. What is the mass percentage of methyl alcohol in solution ?

Options

A. ` 30% `
B. ` 50% `
C. ` 70% `
D. ` 75% `

Explanation

To find the mass percentage of methyl alcohol in the solution, we can follow these steps:

### Step 1: Determine the mass of methyl alcohol and water
- Mass of methyl alcohol = 15 grams
- Mass of water = 35 grams

### Step 2: Calculate the total mass of the solution
- Total mass of the solution = Mass of methyl alcohol + Mass of water
- Total mass = 15 g + 35 g = 50 grams

### Step 3: Use the mass percentage formula
The formula for mass percentage is given by:

\[ \text{Mass percentage} = \left( \frac{\text{mass of solute}}{\text{total mass of solution}} \right) \times 100 \]

In this case, the solute is methyl alcohol.

### Step 4: Substitute the values into the formula
- Mass of solute (methyl alcohol) = 15 grams
- Total mass of solution = 50 grams

Substituting these values into the formula:

\[ \text{Mass percentage of methyl alcohol} = \left( \frac{15 \, \text{g}}{50 \, \text{g}} \right) \times 100 \]

### Step 5: Perform the calculation
\[ \text{Mass percentage of methyl alcohol} = \left( \frac{15}{50} \right) \times 100 = 0.3 \times 100 = 30\% \]

### Final Answer:
The mass percentage of methyl alcohol in the solution is **30%**.

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