How to Calculate the Concentration of Nitric Acid?

What was the concentration of nitric acid if 24.2 g of magnesium hydroxide is needed to completely neutralize 658 mL of nitric acid?

a. 3.71 g/L

b. 7.42 g/L

c. 11.13 g/L

d. 14.84 g/L

Answer:

The concentration of nitric acid can be calculated by dividing the amount of substance of nitric acid by the volume in liters. In this case, the concentration of nitric acid can be found by converting the given mass of magnesium hydroxide to the amount of substance, determining the amount of substance of nitric acid using the stoichiometry of the reaction, and dividing the amount of substance of nitric acid by the volume.

To calculate the concentration of nitric acid in this scenario, we need to follow these steps:

1. Determine the amount of substance of magnesium hydroxide (Mg(OH)₂) used, which is 24.2 g.

2. Convert the volume of nitric acid to liters. 658 mL is equal to 0.658 L.

3. Calculate the amount of substance of nitric acid. Since the reaction is 1:2 between Mg(OH)₂ and HNO₃, the amount of substance of HNO₃ is twice the amount of substance of Mg(OH)₂ used.

4. Finally, calculate the concentration of nitric acid by dividing the amount of substance of nitric acid by the volume. This will give us the concentration in g/L.

By following these steps, you can determine the concentration of nitric acid after neutralizing it with magnesium hydroxide. Remember to consider the stoichiometry of the reaction to accurately calculate the concentration.