The sum of protons and neutrons in an atomic nucleus would be the MASS NUMBER.
Answer:
A precipitation reaction is one in which substances in solution are mixed and an insoluble product is made. The insoluble product is called a precipitate and can be seen as a solid forming in the reaction mixture.
I believe the mass of the product will be 400 grams. This is because according to the law of conservation of mass, mass is neither created nor destroyed . In a closed system, the mass of reactants is equal to mass of products. Therefore, since the total mass of the reactants is 400 grams then the mass of the products will still be 400 grams
