Re: How do you add a specific quantity (ppm) of chloride ions using HCL?

Yes, it's confusing isn't it! ppm is a rather ambiguous way of expressing 
things and chemists usually use g/l or molarity now. However, let's have a 
go...

Assuming it means  one chloride ion per million water molecules, I 
estimate 50ppm to be approx 0.03 molar. The 35% hydrochloric acid you have 
is approx 12M, so it needs diluting by a factor of about 500 in the final 
mix of chemicals. 

REMEMBER for safety with all acids you must add small amounts of ACID TO 
WATER and then dissipate the heat.

Hope that helps. Hope it works!

Sorry for the delay in replying.

Kevin