Paper Shampoo Litmus Paper For Shampoo?

Litmus paper for shampoo? - paper shampoo

I'm a student hairstyling, and we have an extension, which is an ongoing project. He is not through until 1 December, but now I want to finish as it is a huge project.

In a parallel project, we need to talk about the pH scale. It marks also based on creativity. I remember in school when I held chemistry, we have done tests with litmus paper.

I thought of different shampoos and take test with litmus paper to determine the pH and to see what's best for bleached the different types of hair (blonde hair, gray hair resistant virgin hair, etc..)

Now my question is in two parts - one part, then they really can? To ensure the consistency of thick liquid shampoo is not easy.

My second question is where to buy litmus paper to check out eBay or online? Something like this would be perfect:
http://i20.ebayimg.com/08/i/001/10/db/8d ...

Thank you all!