A 0.10 M HF solution is 8.4% ionized. Calculate the H^+ ion concentration.
Here is my line of thought. For every mole HF disolved yeilds one mole of H^+. Since there is ).10 M HF, and the solution is 8.4% ionized = 0.84 M. Is this correct?
I don't know where to start. First, you're line of thought is not quite correct.
1 mol HF dissolved will NOT yield 1 mol H^+ BECAUSE HF is not 100% ionized. That would be so if it were 100% (a strong acid but as you know, HF has a Ka of about 1 x 10^-4). But your thinking is correct on the point that HF ionizes to yield H^+ and for every 1 mol HF that ionizes, the yield is 8.4% (0.084) or 1 x 0.084. So for 0.1, it would be just 0.1 x 0.084 =
Your line of thought is on the right track, but there is a small calculation error. Let's correct it:
Given that the HF solution is 0.10 M and 8.4% ionized, we need to calculate the concentration of the H+ ions.
First, let's find the moles of HF that are ionized:
Moles of ionized HF = 0.10 M * 0.084 (ionization percentage)
Moles of ionized HF = 0.0084 moles
Since every mole of HF dissociates to produce one mole of H+ ions, we can say that the concentration of H+ ions is also 0.0084 M.
Therefore, the H+ ion concentration in the 0.10 M HF solution that is 8.4% ionized is 0.0084 M.
Your line of thought is on the right track, but there seems to be a small confusion in your calculation. Let me guide you through the correct steps to calculate the H^+ ion concentration.
First, you correctly noted that for every mole of HF dissolved, it yields one mole of H^+ ions. Therefore, the concentration of H^+ ions will be equal to the concentration of the HF solution that is ionized.
Given that the HF solution is 0.10 M and 8.4% ionized, we need to determine the actual concentration of ionized HF. To do this, we can use the formula:
% ionization = (concentration of ionized HF / concentration of HF solution) x 100
Plugging in the values:
8.4 = (concentration of ionized HF / 0.10) x 100
To solve for the concentration of ionized HF, we can rearrange the equation:
(concentration of ionized HF / 0.10) = 8.4 / 100
Now, we can isolate the concentration of ionized HF:
concentration of ionized HF = (8.4 / 100) x 0.10
concentration of ionized HF = 0.084 M
Therefore, the concentration of H^+ ions is 0.084 M, not 0.84 M as you calculated.