[Zydon]

Hi, I am doing an experiment with Chlorine where I will be testing how the ppm change as the PH of the solution it is in changes. I would like to know, after putting chlorine into the solution. how would I then measure the ppm if there has been a change?

[Arkcon]

So, you want to measure two things -- ppm of Cl₂ dissolved, and pH.  So you have a way of measuring pH.  How will you measure ppm Cl in solution?  You can't weigh it, like if you were dissolving a solid, or measure it, like you were mixing in a liquid.  You will have to figure out some tricks, because you are using a gas.