Sapling HW Q7

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Evonne Hsu 1J
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Sapling HW Q7

Postby Evonne Hsu 1J » Sun Jan 17, 2021 2:46 pm

Can someone please explain the step-by-step process of this question? Thank you!
Screen Shot 2021-01-18 at 6.45.46 AM.png

Stuti Pradhan 2J
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Re: Sapling HW Q7

Postby Stuti Pradhan 2J » Sun Jan 17, 2021 5:24 pm

First, convert the Ka value to Kb using the equation Kw=Ka x Kb where Kw is 1.0 x 10^-14 since the salt acts as a weak base. Then set up an ICE table for the equation ClO- + H2O <--> HClO + OH-, using 0.056 as the initial value. Set the Kb value equal to [HClO][OH-]/[ClO-], and solve for the OH- concentration. Use the OH- concentration to figure out the pOH, which can then be converted to the pH.

Hope this helps!

Ashley Kim 3H
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Re: Sapling HW Q7

Postby Ashley Kim 3H » Sun Jan 17, 2021 5:50 pm

In this problem, you can solve for Kb because Ka is given since Kb = Kw/Ka. After you get the value of Kb, you would set up an ICE chart to make an equation for Kb. In this case, it would be Kb = [HOCl][OH-]/[OCl-]. Since HOCl and OH- would be regarded as "x" by using the ICE chart, you can solve for x because of the Kb value and the concentration value for OCl-. After finding x, you can find the pOH by taking the -log of the OH- concentration. After that, you would subtract pOH from 14 to get the pH. Hope this helps!

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Re: Sapling HW Q7

Postby arisawaters2D » Sun Jan 17, 2021 5:57 pm

How would this problem be different if it was a strong acid?

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