How many moles are there in 200 grams of CI?

There are approximately 70.906

Formula for moles to grams is n=m/mm; moles is = mass divided by molar mass. molar mass if found under the chemical symbol of the chemical in the periodic table. For chlorine the molar mass is 35.453. so you would do 200/35.453 to get the moles which is 5.64 moles. however i would double check if the chemical is Cl or Cl2 because if chlorine is in its gas phase it usually diatomic (Cl2) in which case you wouldd just double the moles mass