A 6% of urea is isotonic with

Options

A. 1M solution of glucose
B. `0.05M` solution of glucose
C. 6% solution of glucose
D. 2.5% solution of glucose

Explanation

To determine which solution is isotonic with a 6% urea solution, we need to calculate the molarity of the 6% urea solution and then find a solution with the same molarity.

### Step-by-Step Solution:

1. **Understand the Definition of Isotonic Solutions**:
- Isotonic solutions have the same osmotic pressure, which means they have the same molar concentration of solute.

2. **Calculate the Molarity of 6% Urea Solution**:
- A 6% urea solution means there are 6 grams of urea in 100 mL of solution.
- The molar mass of urea (NH₂CONH₂) is approximately 60 g/mol.

3. **Use the Formula for Molarity**:
- Molarity (M) is calculated using the formula:
\[ M = \frac{\text{mass of solute (g)}}{\text{molar mass of solute (g/mol)} \times \text{volume of solution (L)}} \]
- Convert 100 mL to liters:
\[ 100 \text{ mL} = 0.1 \text{ L} \]

4. **Plug in the Values**:
- Mass of urea = 6 g
- Molar mass of urea = 60 g/mol
- Volume of solution = 0.1 L
\[ M = \frac{6 \text{ g}}{60 \text{ g/mol} \times 0.1 \text{ L}} = \frac{6}{6} = 1 \text{ M} \]

5. **Identify the Isotonic Solution**:
- Now, we need to find a solution with the same molarity (1 M).
- Among the options given, we look for a solution that has a molarity of 1 M.
- The first option is a 1 M glucose solution, which is isotonic with the 6% urea solution.

### Conclusion:
The 6% urea solution is isotonic with a **1 M glucose solution**.