soap

[penpaperaser]

I've always been wondering...Soap has a bitter taste, soapy feel and is an alkali right? But alkalis has a pH higher than 7. Does that make the soap; Johnson's pH 5.5 an acid or an alkalis? And why?

[chrisrob]

The pH scale for acids / alkalis goes from 1 (very acidic) to 14 (strong alkali) with neutral being 7. Therefore a pH of 5.5 would make it mildly acidic.

[penpaperaser]

It still has a soapy feel though, so is it still counted as an acid?

[chrisrob]

Sorry to disabuse you. Most soaps are acidic. (Have you heard of carbolic acid?) Soaps are acidic salts of sodium or potassium fats; sodium based soaps are hard and potassium based soaps are soft.

[penpaperaser]

Oh, okay, thank you!

[gen2]

I think I can explain where penpaperaser is getting confused.

First a fact:-
Soaps can be formed by the reaction between an alkali and a fat.

If you were to rub an alkili between the fingers (not advised with the strong ones), then it reacts with fats in the skin to form a soap and obvously, it feels soapy. It is not the alkali that feels soapy, it is the soap that is formed that feels soapy. Soap from any other source will also feel soapy, but that doesn't mean it is an alkali since no reaction has to take place with the skin.

[peanut273]

1,2,3,4,5 and 6 are all ACID on the pH scale. (such as Vinegar)

7 is neutral (like water)

8,9,10,11,12,13 and 14 are all alkali.

Most soaps are actually alkali.

If ur soap is 5.5 its Acidic but not much & close to 7 (neutral). as the higher on the pH scale the more acidic the substance is!