A student prepares a 0.28 M solution of acetic acid. If the Ka of the acid is 1.76 x 10^-5, then what is the pH of the solution?

Question

4.76

0.55

5.31

2.65

I got 2.65 as my answer. :)

Answer 1

1.76e-5=x^2/(.28-x)
checking your answer: 2.65>>>concH=10^-2.65== 0.00223872114
1.76e-5= ( 0.00223872114)^2/(.28- 0.00223872114)
= 1.80e-5

I agree 2.65 is it.