pH equation

[Maggie Messer 1A]

Is there a specific pH equation we should know? If so is it the log equation? Thank you!

[Sharlene Duong 3E]

I think we should know pH = -log[H+] because it is on the Constants and Equations sheet. We should probably also know that pOH = -log[OH-] and pH + pOH = 14.

[loganchun]

I think knowing these 4 equations will be good to know for the test:
1.0 x 10^14 = [H+][OH-]
14.00 = pH + pOH
pH = -log[H+]
pOH = -log[OH-]

[Aaron Tang 2F]

All the equations that Logan listed can be really helpful in certain situations, but in my experience the pH = -log[H+] equation will probably be the most useful equation of the bunch on tests. It's also really neat that you can derive these equations from each other.

[joshua_quinn_1C]

To find the pH value, you can use the equation pH = -log[H+]. For pOH, which is less common, you can either subtract the pH value from 14 or use pOH = -log[OH-]

[QUEP 2F]

Hi!

From prior experience, knowing pH = -log[H+] and pOH = -log[OH-] has typically the most useful (especially for tests). I would also familiarize myself with 1.0 x 10^14 = [H+][OH-].

[Joshua Lee 3C]

I believe that in this case, the equations pH=-log[H+] and pOH=-log[OH-]. Also, keep in mind that pOH and pH should add up to a total of 14. Also conceptually remember that these equations, and the concept of pH, are for convenience, and are simply an easier method to measure the concentration of the molecules and ions without needing to use scientific notation.

[Anika Scott 3A]

In terms of pH, some of the equations that I think would be important to know include: 1.0 x 10^14 = [H+][OH-],14.00 = pH + pOH, pH = -log[H+], pOH = -log[OH-]. Also, keep in mind that a smaller pH is more acidic in contrast to a larger pH being more basic.

[Santiago Chang 2K]

The specific pH equation is:

pH = -log[H+].

Other helpful equations are:

pOH = -log[OH-]
pH + pOH = 14
1 x 10^(14) = [H+][OH-]

Hope this helps!

[Ainsley DeMuth 1H]

I believe the most helpful pH equation is going to be pH = -log[H+].

[Joseph Liao 3C]

Definitely know the pH = -log(H+) equation for the final! You'll probably need to do some calculations with it. Then, it should be easy to remember that pOH = -log(OH-), and to convert between the two, you can simply subtract pH or pOH from 14 to find the other one.

[Caitlin Beale 3E]

The equations on achieve are:
1.0 x 10^14 = [H+][OH-]
14.00 = pH + pOH
pH = -log[H+]
pOH = -log[OH-]

and should be memorized as they are not on the Constants and Equations sheet.

[505686385]

5 important equations to keep in mind
Finding H+ concentration: pH = -log[H+]
[H+] = 10^(-pH)
Finding OH- concentration: pOH = -log[OH-]
[OH-] = 10^(-pOH)
Finding pH or pOH when given one of the values: pOH + pH = 14

[005778617]

It would definitely be most helpful to remember that pH = -log[H+]. But you can also memorize the others mentioned in the previous few posts.

[Cecilia Lei 3K]

I think we should understand that pH=-log[H+] and when calculating the pH of strong acids and bases, this equation can be used directly.

[Skylar Lo 2C]

Just know how to get between [H+], [OH-], pH, and pOH. This website has a good diagram: https://www.sciencegeek.net/APchemistry ... ations.htm

[Rebecca Preusch 2C]

pH=-log[H+]
pH=14-pOH

[Jessica Servoss 1H]

Definitely know that pH = -log[H+] and the pOH can be calculated by subtracting the pH from 14 :)

[N Kanuri 2E]

Adding onto what everyone else has said, understanding the relationship between logarithms and exponents is important to derive the formula for [H+] or [OH-] from pH or pOH.

1.0 x 10^14 = [H+][OH-]
14.00 = pH + pOH
pH = -log[H+]
pOH = -log[OH-]

[H+] = 10^-pH
[OH-] = 10^-pOH

[Vanessa Wiratmo 3k]

Hello,

You should know that the equation to calculate pH as:
pH=-logbase 10 [H+]

You should also know how to find [H+] using this equation
[H+]=10^(-pH)

If you are given the pOH, you can use the equation below to figure out pH
14=pH+pOH

[Katherine Li 1A]

You should just need to know that pH = -log[H+]. Also keep in mind that a lower pH means a higher [H+]! In other words, lower pH means more acidic.

[Abigail Tran 14a]

here are some important pH equations
pH = -log[H+]
pOH = -log[OH-]
1.0 x 10^14 = [H+][OH-]
14.00 = pH + pOH

[Niyati 1F]

pH = -log[H]
pOH = -log[OH]
pH + pOH = 14

[Audrey Banzali-Marks 1A]

pH = -log[H+] is probably the most helpful equation to memorize. You calculate pOH almost the exact same way, only you concentrate on the concentration of OH- ions because bases are electron donors/hydrogen acceptors and therefore more negative. That equation is pOH = -log[OH-]. Remember that any time we have p, that basically means take the -log of whatever's after it! (ex: Ka = 10^-3 so pKa = -log(10^-3) = 3)

[SuryaDham 3E]

i think we should know that pH = -log[h30]+, pOH = -log[OH]-, and pOH + pH = 14