Hello everyone, thank you for stopping by to read another post on chemistry topics. Today I'll be talking about pH and pOH.
Why you should understand pH and pOH:
pH and pOH are both measures of acidic-ness and basic-ness in solution. Acid-base chemistry is a huge part of chemistry.
Key Ideas
- The pH scale
- The pOH scale
- Relating the two scales
- formulas for pH and pOH
The pH scale
The pH scale quantifies the amount of hydronium ion present in solution. On the pH scale, a low number corresponds with a large amount of Hydronium and a small amount of Hydroxide. A large number on the pH scale represents a low concentration of hydronium and a large concentration of hydroxide.
The pH scale is the more typical measurement of acidity and basicity.
The pOH scale
The pOH scale quantifies the amount of hydroxide in solution. On the pOH scale, a low number corresponds with a large amount of hydroxide and a small amount of hydronium. While a high pOH corresponds with a low hydroxide concentration and a high hydronium concentration.
Relating the two scales
The pH and pOH scales are inversely related. Red is commonly used to represent acidic solutions while Blue is commonly used to represent basic solutions. In the image below you can see the inverse relationship particularity clearly by looking at the colors.
formulas for pH and pOH
Below are the formulas for pH and pOH. Recall that a "p" at the beginning of any formula means "take the negative log of..."
In the formula for pOH the "p" says that we should "take the negative log of OH". The formula for pOH is the negative log of the concentration of hydroxide.
In the formula for pH the "p" says that we should "take the negative log of H". The formula for pH is the negative log of the concentration of hydronium.
Summary
- The pH scale quantifies the amount of hydronium ion present in solution.
- The pOH scale quantifies the amount of hydroxide in solution.
- The pH and pOH scales are inversely related.
- The formula for pOH is the negative log of the concentration of hydroxide.
- The formula for pH is the negative log of the concentration of hydronium.
I hope this post on pH and pOH has been helpful. If you have any questions feel free to comment below or message me privately. You can also look at my youtube video I made describing pH and pOH.
- Saren
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