4.25 grams of ammonia are dissolved to form 4L aqueous solution. Calculate the active mass.

Explanation

To calculate the active mass (molarity) of ammonia in the solution, we will follow these steps:

### Step 1: Calculate the number of moles of ammonia
To find the number of moles, we use the formula:
\[ \text{Number of moles} = \frac{\text{mass (g)}}{\text{molar mass (g/mol)}} \]
Given:
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