The 10x rule is incorrect, and yes, CC already has chlorine attached to the ammonia so less chlorine is needed to get the job done.
This rule is important to live by for chlorine to ammonia levels.
3HOCl + 2NH3 ---> 2N2(g) + 3H2O + 3H+ + 3Cl-
Hypochlorous Acid + Ammonia ---> Nitrogen Gas + Water + Hydrogen Ion + Chloride Ion
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