Question

What is the pH of a solution prepared from mixing 100 mL of 0.2 M HCl and 50 mL of 0.1 M HNO3?

Answer 1

Concentration of mixture = (n1*C1*V1+ n2*C2*V2) / (V1+V2)

where C1 --> Concentration of 1 component

V1-->volume of 1 component

C2 --> Concentration of other component

V2-->volume of other component

n1 --> number of particle from 1 molecule of 1st component

n2 --> number of particle from 1 molecule of 2nd component

we have below equation to be used:

[H+] = (n1*C1*V1+ n2*C2*V2) / (V1+V2)

= (1*0.2*100+1*0.1*50)/(100+50)

= 0.1667 M

we have below equation to be used:

pH = -log [H+]

= -log (0.1667)

= 0.778

Answer: 0.778