In the reaction 2na + cl2 → 2nacl, the products are a. half the reactants. b. twice the reactants. c. the same as the reactants. d. different from the reactants.

The law of conservation of mass states that mass is neither created nor destroyed, but can only change from one form to another.
Applying this law, we will find that the first two choices are rejected (as they do not follow this law).

Now, we are left with choices C and D.
If we consider the reaction, sodium and chlorine react together to form sodium chloride which is different from the two reactants.

Based on the above, the correct choice is:
D. different from the reactants