Final answer:
To find the concentration of nitric acid, you need to use the concept of dilution. By mixing 200.0 mL of aqueous nitric acid with 300.0 mL of 0.200 M Mg(NO₃)₂ solution, you can calculate that the concentration of nitric acid is 0.120 M.
Step-by-step explanation:
To find the concentration of nitric acid, we need to use the concept of dilution. Dilution is the process of adding solvent to a solution to decrease its concentration. In this case, we have mixed 200.0 mL of aqueous nitric acid with 300.0 mL of 0.200 M Mg(NO₃)₂ solution to give a solution with a nitrate ion concentration of 0.500 M.
We can use the dilution formula: C1V1 = C2V2
Where C1 is the initial concentration, V1 is the initial volume, C2 is the final concentration, and V2 is the final volume.
In this case, the initial concentration is the concentration of Mg(NO₃)₂ solution (0.200 M) and the initial volume is the volume of Mg(NO₃)₂ solution (300.0 mL). The final concentration is the concentration of nitric acid and the final volume is the sum of the initial volumes of the two solutions (200.0 mL + 300.0 mL = 500.0 mL).
Substituting these values into the dilution formula, we get:
0.200 M x 300.0 mL = C2 x 500.0 mL
Solving for C2, the concentration of nitric acid, we find:
C2 = (0.200 M x 300.0 mL) / 500.0 mL = 0.120 M
Therefore, the concentration of nitric acid is 0.120 M.