Question

200 mL M/2 HCl and 300 mL M/10 HNO3 were mixed. Concentration of hydrogen ion [H+], in the mixture is

Answer 1

Answer:

Hii

Explanation:

1 M H

2

SO

4

solutio has 2M H

+

ions

Therefore, moles of H

+

in:

200 ml of 1M H

2

SO

4

= 2×0.2L×1mol/L=0.4

300 ml 0f 3M HCl = 0.3L×3mol/L=0.9

100 ml 0f 2M HCl = 0.1L×2mol/L=0.2=1.5

Total volume = 1L

So [H

+

] = 1.5 mol/L

Answer 2

Given:

The molarity of HCl solution, M1 = 1/2 = 0.5 M

The volume of HCl solution, V1 = 200 ml

The molarity of HNO3 solution, M2 = 1/10 = 0.1 M

The volume of HNO3 solution, V2 = 300 ml

To Find:

The concentration of hydrogen ions [H+] in the mixture.

Calculation:

- Total volume = Volume of HCl + Volume of HNO3

⇒ V = V1 + V2

⇒ V = 200 + 300

⇒ V = 500 ml

- Using the molarity equation, we get:

M V = M1 V1 + M2 V2

⇒ M × 500 = 0.5 × 200 + 0.1 × 300

⇒ M = (100 + 30) / 500

⇒ M = 130 / 500

⇒ M = 0.26 M

- Since both HCl and HNO3 are monobasic acids, they dissociate completely and give the same hydrogen ion concentration as the molarity of the solution.

- Hence, the concentration of hydrogen ions [H+] in the mixture = 0.26 M