I was wondering why we need substances which contain acid in acidity. Can someone help me out? 

59 minutes ago, mundane said:

I was wondering why we need substances which contain acid in acidity. Can someone help me out? 

IOW, why are acids so important, so central to chemistry?

They say the basic unit of chemical exchange is the electron. But that's only half the story. Protons are very powerful mediators of chemical reactions too. And the reason is that the size of a hydrogen atom compared to the size of just a proton (ionized hydrogen) is like the size of the Earth compared to the size of an orange.

So when you have a substance that  is capable of liberating protons, you're liberating myriads of little "positive versions of the electron," so to speak.

That's why there is no central concept in chemistry of how easily a substance can liberate any other ion, like e.g. Na⁺. But liberating H⁺ is very powerful, very reactive. Protons are elementary particles, small as can be, and move about very freely, especially in aqueous solution.

The mitochondria in your cells are powerful proton-pumps.

Edited October 24, 20205 yr by joigus

To live with the help of them. Indeed, it is not a secret that people must have acidicity in their body.