Introduction to pH | Biology foundations | High school biology | Khan Academy

The pH scale is used to determine the acidity or basicity (alkalinity) of a substance. Acidic substances have pH values below 7, while basic substances have pH values above 7; neutral substances have a pH of 7. The pH scale is logarithmic, so each step represents a 10-fold change in concentration.

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[jwyz]

Been using the pH scale for three years now in school with three separate teachers and not a single one managed to explain it the way you did in a five minute video. Thank you

[xLucky]

Best explanation of the pH scale I've seen by far. Thank you Sal and all of Khan Academy for all of your excellent lessons!!!

[lucasAA]

I already knew this, but the way you explained was amazing

[sashatoao]

Sal. I wasn't even thinking about drinking acidic or basic stuff. Now I am.

[TheJoshtheboss]

Is the scale counter intuitive or it's just me? The more hydrogen ion present (the higher the H content) the lower you go on the scale?

[leaderlogic]

Wow, this explanation was quicker and more informative than I remember from school! 😬 Awesome video!

[peterdunlop]

I've never heard of, or remember from school, alkalines being called basic.

[starbug]

Hi you said you’re not going to go more in depth in this video. Where can I find information that goes more in depth?

[Error-eo]

I have a doubt lemon does not damage my skin when I put it on bruh pls explain me .

[leaderlogic]

😂 I've just found the Khan Academy Chemistry playlist = time to nerd!

[fificovfefe]

Shouldn't you talk about pH being voltage...and the different voltages inside and outside the cells?

[munshibarkatali]

Then why doesn't our stomach burst when we drink water as our stomach has acid and water reacts with acid and it's reaction is exothermic

[ABCD-mspr]

What about drinking lemon water, does it alkaline your body?

[lucasAA]

Being basic, is posting a photo of you drinking starbucks in instagram

[احلامقيدالتنفيذ-نص]

Yr lessons are amazing but i need translation cz i cant understand everything in video, Any help here plz 😟????