How to Calculate OH- Concentration
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How to Calculate OH- Concentration
Hi, how do I calculate the OH- concentration given the H+ concentration as in question 5 in the Achieve homework?
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Re: How to Calculate OH- Concentration
We know that the product of the H+ and OH- concentration is 10^-14, so given the H+ concentration, you can divide 10^-14 by the H+ concentration to find the OH- concentration.
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Re: How to Calculate OH- Concentration
This is a bit of lengthy method but how I did it was I subtracted the pH from 14; this gives the pOH value with which you can then use to calculate the concentration of OH- ions through the formula pOH = -log([OH-]), which you would rearrange to [OH-] = antilog(-pOH).
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Re: How to Calculate OH- Concentration
There are different ways you could. The fastest would probably be using 1.0×10−14=[H+][OH−]. Plug in H+ concentration to solve for OH- concatenation.
Another way would be first use H+ concentration to calculate pH with pH=−log[H+], then 14-pH to fine pOH, then do 10^-pOH to find OH- concentration. This might a good way if the problem also asks for pH and pOH.
Another way would be first use H+ concentration to calculate pH with pH=−log[H+], then 14-pH to fine pOH, then do 10^-pOH to find OH- concentration. This might a good way if the problem also asks for pH and pOH.
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Re: How to Calculate OH- Concentration
If given [H+], the fastest way to find [OH-] would be to use the equation: 1.0x10^-14 = [H+][OH-].
The other way to solve this is to use: 14 = pH + pOH, pH = -log[H+], pOH = -log[OH-]. With the given [OH-], find pOH. Then, use 14 = pH + pOH to find pH. Take this pH and plug into pH = -log[H+]. Solve, 10^-pH to get [H+].
The other way to solve this is to use: 14 = pH + pOH, pH = -log[H+], pOH = -log[OH-]. With the given [OH-], find pOH. Then, use 14 = pH + pOH to find pH. Take this pH and plug into pH = -log[H+]. Solve, 10^-pH to get [H+].
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Re: How to Calculate OH- Concentration
To find the [OH-] given [H+], use 1.0 x 10^-14 = ([OH-])([H+]). This means that is you have the [H+], you just need to divide it by 1.0 x 10^-14 to get [OH-].
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Re: How to Calculate OH- Concentration
In order to determine the [OH-] from [H+], you would need to divide [H+] by 1*10^-14.
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Re: How to Calculate OH- Concentration
Use the equation 1.0 x 10^-14 = ([OH-])([H+]). First you isolate [OH-] and then plug the [H+] in the equation.
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Re: How to Calculate OH- Concentration
To find the OH- concentration given the H+ concentration, you can use the equation 1.0x10^-14/[H+].
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Re: How to Calculate OH- Concentration
the product of [OH-] and [H+] are 10^-14, so you can divide 10^-14 by [OH-] to find [H+] and vice versa
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Re: How to Calculate OH- Concentration
Once you know the [H+] concentration you should be able to find the [OH-] concentration since the equation for the [OH-] concentration is 1.0 x 10^-14 / [H+].
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Re: How to Calculate OH- Concentration
You can calculate the pH from H+ concentration. pOH=14-pH, so you can calculate the pOH and from that the concentration of OH-.
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Re: How to Calculate OH- Concentration
The product of the H+ and OH- concentration =10^-14, so if you have the H+ concentration, you can divide 10^-14 by the H+ concentration to find the OH- concentration.
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Re: How to Calculate OH- Concentration
the product of the OH- and H+ concentration are equal to Kw, which is 10^-4. Thus, if you have one of the concentrations, you can divide it by Kw to find the other. Additionally, you could also find the pH or pOH and then use the 10^-pH to find the concentration.
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Re: How to Calculate OH- Concentration
When given H+, first find pH with the equation pH = -log[H+]. Then find pOH with the equation pOH = 14 - pH. Finally, you can find OH- with the equation [OH-] = 10^-pOH.
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Re: How to Calculate OH- Concentration
Using the relationship [OH-][H+] = 1.0 x 10^-14, plugging in the [H+] and then simplifying would allow you to calculate the [OH-].
Re: How to Calculate OH- Concentration
the feedback of the solution gives you helpful formulas to use!
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