Answer:
4 grams
Step-by-step explanation:
If in an experiment, we have 4g of reactants, the mass of the products will also be 4g.
This is in compliance with the law of conservation of mass in a chemical reaction.
According to this law,
"in a chemical reaction, matter is neither created nor destroyed but changed from one form to another".
If:
A + B → C
4g 4g
mass of A and B must be equal to the mass of the product according to the law of conservation of mass.