Question

13) a 0.10 HF solution is 8.4% ionized. Calculate the H+ ion concentration.

Someone solve this by working it out for me please, I have no clue where to even start.


One more question...Im actually doing homework right now and came across the problem

10)"what is the concentration of H+ in a 2.5 M HCL solution?"
I am thinking the answer is 2.5 M because HCL is a strong acid and dissocociates completely, right?

THEN i ran across this question-
12) What is the OH- Ion concentration in a 5.2 x 10^-4 M HNO3 solution?
Wouldnt that mean that OH- ion concentration be 5.2 x 10^-4M solution?

because it too is a strong acid and dissocociates completely? I looked it up on here and everyone keeps getting 1.92 x 10 ^11. I understand how they got that...but i thought the rule was if it was a strong acid the number of the products is automatically the number of the reactants. Someone please help me understand this. does this rule only apply to the H+ concentration?

Answer 1

10) is right

12) from HNO3 if they ask to find out the H⁺ then whatever you are saying is correct but they are asking OH-

so

5.2 x 10-4 M HNO3 releases 5.2 x 10-4 M H+

K water = [H+] [OH-] here K is ionic product of water which is equal to 1x10^-14 this you might hered in class right?

substitutr you H+ and Kw value in the above eqation you will get the concentration of OH-

1x10^-14 = [5.2 x 10-4 M] [OH-]

[OH-] = 1.92x10^-11 Molar

13) For every mole HF disolved yeilds one mole of H^+

Since there is 0.10 M HF, and the solution is 8.4% ionized 8.4% means 8.4/100

so 0.1x8.4/100 = 0.0084 M