Calculate the mass of water ( in g ) required to make 250g of 25% solution of glucose.

Explanation

To calculate the mass of water required to make a 250 g solution of 25% glucose, we can follow these steps:

### Step 1: Understand the definition of a percentage solution
A 25% solution of glucose means that 25 grams of glucose is present in every 100 grams of the solution.

### Step 2: Calculate the mass of glucose in the solution
Since we want to prepare 250 grams of a 25% glucose solution, we can use the formula for mass percentage:
\[ \text{Mass of solute (glucose)} = \left(\frac{\text{Percentage}}{100}\right) \times \text{Total mass of solution} \]
Substituting the values:
\[ \text{Mass of glucose} = \left(\frac{25}{100}\right) \times 250 \, \text{g} = 62.5 \, \text{g} \]

### Step 3: Calculate the mass of water needed
The mass of the solution is the sum of the mass of the solute (glucose) and the mass of the solvent (water). Therefore, we can find the mass of water by subtracting the mass of glucose from the total mass of the solution:
\[ \text{Mass of water} = \text{Total mass of solution} - \text{Mass of glucose} \]
Substituting the values:
\[ \text{Mass of water} = 250 \, \text{g} - 62.5 \, \text{g} = 187.5 \, \text{g} \]

### Conclusion
The mass of water required to make 250 g of a 25% glucose solution is **187.5 g**.

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