Can acidic and alkaline solutions soften hair?.... if so, how?

Question

In the pH scale hair is in the scale of 3.5 to 5.5.
I think I can use acidic substances to soften my hair.

My cosmetology instructor asked me to find out how hair can be soften using two acidics.

Answer 1

I'd imagine acid can soften hair by destroying or otherwise denaturing the proteins.

Answer 2

Hair conditioners tend to be alkaline and made of fatty amines. But these products are made from fatty acids.

so perhaps adding some fatty acids together (for example stearic acid and cetyl acid) might have some benefit