The atomic number of chlorine is 17. The atomic number of magnesium is 12. What is the formula for magnesium chloride? Naim 02:18 Biology The atomic number of chlorine is 17. The atomic number of magnesium is 12. What is the formula for magnesium chloride? A) Mg2Cl2 B) Mg2Cl C) MgCl D) MgCl3 E) MgCl2 Answer: E Learn More : Share this Share on FacebookTweet on TwitterPlus on Google+