How to take the log to get the pH?

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tonyhu
Posts: 57
Joined: Tue Sep 24, 2019 12:17 am

How to take the log to get the pH?

Postby tonyhu » Wed Nov 27, 2019 12:13 pm

What does the math function mean?

Sukanya Mohapatra 2G
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Re: How to take the log to get the pH?

Postby Sukanya Mohapatra 2G » Wed Nov 27, 2019 1:10 pm

The formula for pH is pH = -log[H+]. This means pH is the negative base 10 logarithm of the hydrogen ion concentration of a solution. To calculate it, take the log of the hydrogen ion concentration and reverse the sign to get the answer.

AngieGarcia_4F
Posts: 120
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Re: How to take the log to get the pH?

Postby AngieGarcia_4F » Wed Nov 27, 2019 1:21 pm

If you were given a Hydrogen concentration of [H+]=0.1M, for example, and asked to find the pH, you would plug the concentration into the formula pH=-log[H+]; pH=-log[0.1M], and just plug it into your calculator.

Diana Chavez-Carrillo 2L
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Re: How to take the log to get the pH?

Postby Diana Chavez-Carrillo 2L » Wed Nov 27, 2019 2:03 pm

AngieGarcia_4F wrote:If you were given a Hydrogen concentration of [H+]=0.1M, for example, and asked to find the pH, you would plug the concentration into the formula pH=-log[H+]; pH=-log[0.1M], and just plug it into your calculator.


So would our answer just be 1? Also, would this be interpreted as our pH being 1?

Esha Chawla 2E
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Joined: Thu Jul 25, 2019 12:17 am

Re: How to take the log to get the pH?

Postby Esha Chawla 2E » Wed Nov 27, 2019 2:13 pm

Diana Chavez-Carrillo 3J wrote:
AngieGarcia_4F wrote:If you were given a Hydrogen concentration of [H+]=0.1M, for example, and asked to find the pH, you would plug the concentration into the formula pH=-log[H+]; pH=-log[0.1M], and just plug it into your calculator.


So would our answer just be 1? Also, would this be interpreted as our pH being 1?


Yes - the pH would be 1.

On a related note, you can use the formula pOH = -log[OH-] to find the pOH. For example, if your [OH-] concentration were 0.1M, you would plug it into -log[0.1], resulting in a pOH of 1.

Khushboo_3D
Posts: 60
Joined: Wed Sep 18, 2019 12:19 am

Re: How to take the log to get the pH?

Postby Khushboo_3D » Wed Nov 27, 2019 3:38 pm

Diana Chavez-Carrillo 3J wrote:
AngieGarcia_4F wrote:If you were given a Hydrogen concentration of [H+]=0.1M, for example, and asked to find the pH, you would plug the concentration into the formula pH=-log[H+]; pH=-log[0.1M], and just plug it into your calculator.


So would our answer just be 1? Also, would this be interpreted as our pH being 1?



This would be interpreted as being a very strong acid.

BeylemZ-1B
Posts: 95
Joined: Thu Jul 25, 2019 12:17 am

Re: How to take the log to get the pH?

Postby BeylemZ-1B » Wed Nov 27, 2019 7:01 pm

would a really weak base be close to 7? or as far away from 7 as possible?

for example:
would a pH of 8 be more or less basic than a pH of 12?

Eunice Nguyen 4I
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Joined: Sat Aug 17, 2019 12:17 am

Re: How to take the log to get the pH?

Postby Eunice Nguyen 4I » Wed Nov 27, 2019 9:15 pm

BeylemZ-4A wrote:would a really weak base be close to 7? or as far away from 7 as possible?

for example:
would a pH of 8 be more or less basic than a pH of 12?


A pH of 8 would be less basic than a pH of 12. A really weak base would be as far away from 14.

ahuang
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Re: How to take the log to get the pH?

Postby ahuang » Wed Nov 27, 2019 11:12 pm

BeylemZ-4A wrote:would a really weak base be close to 7? or as far away from 7 as possible?

for example:
would a pH of 8 be more or less basic than a pH of 12?


a pH of 8 would be less basic than a pH of 12.


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