pH scale

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Aiden Metzner 2C
Posts: 104
Joined: Wed Sep 18, 2019 12:21 am

pH scale

Postby Aiden Metzner 2C » Sun Dec 01, 2019 5:00 pm

Why is the pH scale from 0-14 if it can be negative and go beyond 14?

Andrew Jang 4D
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Joined: Sat Aug 17, 2019 12:18 am

Re: pH scale

Postby Andrew Jang 4D » Sun Dec 01, 2019 5:17 pm

I would assume that pH values of 0-14 are the most commonly found

Heba Mengesha 3D
Posts: 50
Joined: Sat Sep 07, 2019 12:19 am

Re: pH scale

Postby Heba Mengesha 3D » Sun Dec 01, 2019 5:20 pm

I believe that the pH scale is not limited to 0-14, but most common solutions fall into this range.

gabbymaraziti
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Re: pH scale

Postby gabbymaraziti » Sun Dec 01, 2019 5:20 pm

pH cannot be negative, which is why the formula for calculating pH is -log(H3O+).

J Medina 2I
Posts: 102
Joined: Wed Sep 25, 2019 12:17 am

Re: pH scale

Postby J Medina 2I » Sun Dec 01, 2019 5:20 pm

Most solutions are in this range. Remember that pH is logarithmic so a pH of 15 would have a concentration of ions 10x greater than a solution with a pH of 14, which is not common.

KDang_1D
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Re: pH scale

Postby KDang_1D » Sun Dec 01, 2019 8:29 pm

Solutions can fall outside the 0-14 range. Dr. Lavelle mentioned "superacids" which have a H3O+ concentration > 1x10^0 M and thus would have a negative pH. However, these are uncommon, especially in biological systems. I'm sure the same is true for bases.

Veronica Lu 2H
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Re: pH scale

Postby Veronica Lu 2H » Sun Dec 01, 2019 8:43 pm

In most situations, pH ranges from 0-14

SimranSangha4I
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Joined: Sat Sep 14, 2019 12:17 am

Re: pH scale

Postby SimranSangha4I » Sun Dec 01, 2019 8:44 pm

The 0-14 primarily acts as a scale for most solutions.

MBouwman_4A
Posts: 40
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Re: pH scale

Postby MBouwman_4A » Mon Dec 02, 2019 8:29 am

Most solutions fall between 0 and 14, there are very few acids that would be negative and very few bases that would fall above 14.

Caroline Zepecki
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Joined: Fri Aug 09, 2019 12:16 am

Re: pH scale

Postby Caroline Zepecki » Mon Dec 02, 2019 8:55 am

The pH scale definitely can not go negative because it is the factor 10 of H+ ions, so from a mathematical standpoint it would make no sense to have a negative concentration of H+ ions.

DMuth_1J
Posts: 63
Joined: Thu Jul 11, 2019 12:15 am

Re: pH scale

Postby DMuth_1J » Mon Dec 02, 2019 9:14 am

The 0-14 scale is most of the time all you will have to worry about, but don't be alarmed if your calculations give you a number slightly below 0 or slightly above 14. It is possible in extremely strong acids / bases, but is rare.

305385703
Posts: 102
Joined: Thu Jul 11, 2019 12:15 am

Re: pH scale

Postby 305385703 » Mon Dec 02, 2019 9:16 am

A scale from 1-14 is most common as others have said and it encompasses all solutions found in organic systems.

Christineg1G
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Re: pH scale

Postby Christineg1G » Mon Dec 02, 2019 9:25 am

The pH scale is most common between 0-14, but it is possible to go above or below 0 or 14. In the case of very acidic acids known as super acids, the pH scale goes below 0.


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