Ammonia gas is passed into water, yielding a solution of density `0.93 g//cm^(3)` and containing `18.6% NH_(3)` by weight. The mass of NH3 per cc of the solution is :

Options

A. `0.17g//cm^(3)`
B. `0.34g//cm^(3)`
C. `0.51g//cm^(3)`
D. `0.68g//cm^(3)`

Explanation

To find the mass of ammonia (NH₃) per cc of the solution, we can follow these steps:

### Step 1: Understand the Given Data
- Density of the solution = 0.93 g/cm³
- Percentage by weight of NH₃ = 18.6%

### Step 2: Calculate the Mass of the Solution
Assuming we have 100 g of the solution (this simplifies calculations):
- Mass of NH₃ in the solution = 18.6% of 100 g = 18.6 g
- Mass of the solution = 100 g

### Step 3: Calculate the Volume of the Solution
Using the formula for density:
\[ \text{Density} = \frac{\text{Mass}}{\text{Volume}} \]
We can rearrange this to find the volume:
\[ \text{Volume} = \frac{\text{Mass}}{\text{Density}} = \frac{100 \text{ g}}{0.93 \text{ g/cm}^3} \approx 107.53 \text{ cm}^3 \]

### Step 4: Calculate the Mass of NH₃ per cc of the Solution
Now, we need to find the mass of NH₃ per cm³ of the solution:
\[ \text{Mass of NH₃ per cm}^3 = \frac{\text{Mass of NH₃}}{\text{Volume of solution}} = \frac{18.6 \text{ g}}{107.53 \text{ cm}^3} \approx 0.173 \text{ g/cm}^3 \]

### Step 5: Final Result
Thus, the mass of NH₃ per cc of the solution is approximately:
\[ \text{Mass of NH₃ per cc} \approx 0.173 \text{ g/cm}^3 \]

### Summary
The mass of ammonia per cc of the solution is approximately **0.173 g/cm³**.