Hi. Thanks for your replies.
I was planning on dissolving a acid in water
Dissolving a solid acid, or adding acid solution. Yes, that's the correct way of decreasing pH.
but I am unsure of how to seperate the water from the acid while still maintaining the pH level.
Why do you want to separate them? Please elaborate, as I fell you are misunderstanding something here.
Also note: if you want good control of pH it is better to not just add acid/base, but to use buffers. That's how the research in different pHs is typically carried out.
My experiment was to find how changing the pH level of a solution would impact the absorption of that solution in a super absorbent polymer such as sodium polyacrylate. Based on my learning, I know that HCl will dissociate fully in water and decrease the pH of the solution. However, the Cl will still be in the solution which would have an impact on the absorption, which would introduce another variable. Also, at this point, it is just dilute HCl and I will also need to increase the pH to make it more basic.
Do you want to increase pH or decrease pH?
I was planning on increasing it and decreasing it to find the peak pH level where maximum water is being absorbed.