In the reaction, sodium and chlorine combine to produce sodium chloride. In an instance when four sodium chloride molecules are produced, how many diatomic chlorine molecules went into the reaction?

Question

2Na + CI2 --> ?NaCI

one
two
four six

Answer 1

The balanced equation for the reaction is 2Na + Cl2 → 2NaCl, meaning that for every one molecule of diatomic chlorine (Cl2) that reacts, two molecules of sodium chloride (NaCl) are produced. Therefore, if four molecules of NaCl are produced, there must have been two molecules of Cl2 involved in the reaction. Answer: two.