A solution was prepared by dissolving 0.63g of nitric acid in 10 L of the solution. Calculate its pH.

Explanation

To calculate the pH of a solution prepared by dissolving 0.63 g of nitric acid (HNO3) in 10 L of solution, follow these steps:

### Step 1: Calculate the number of moles of nitric acid (HNO3)
To find the number of moles, use the formula:

\[ \text{Number of moles} = \frac{\text{mass (g)}}{\text{molar mass (g/mol)}} \]

The molar mass of HNO3 is approximately 63 g/mol.

\[ \text{Number of moles} = \frac{0.63 \, \text{g}}{63 \, \text{g/mol}} = 0.01 \, \text{moles} \]

### Step 2: Calculate the concentration of HNO3 in the solution
Concentration (C) is calculated using the formula:

\[ C = \frac{\text{Number of moles}}{\text{Volume of solution (L)}} \]

Given that the volume of the solution is 10 L:

\[ C = \frac{0.01 \, \text{moles}}{10 \, \text{L}} = 0.001 \, \text{moles/L} = 1 \times 10^{-3} \, \text{mol/L} \]

### Step 3: Calculate the pH of the solution
The pH is calculated using the formula:

\[ \text{pH} = -\log[H^+] \]

Since nitric acid is a strong acid, it fully dissociates in solution, meaning the concentration of H+ ions is equal to the concentration of HNO3:

\[ [H^+] = 1 \times 10^{-3} \, \text{mol/L} \]

Now, substitute this value into the pH formula:

\[ \text{pH} = -\log(1 \times 10^{-3}) \]

Using logarithmic properties:

\[ \text{pH} = -(-3) = 3 \]

### Final Answer
The pH of the solution is **3**.

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