How many g of H2 is formed from 2.4 g H20 according to the following reaction.

2H2O--->2H2O+O2
I believe the answer is .27g
However, I can't understand how to work the problem completely out or one like it, if someone could please explain the formula it would be appreciated.

Would you believe none? No H2 is involved in the equation. In fact the equation is wrong because

a. it isn't balanced.
b. the product and reactant are the same.