X and Y chemically react to form a new product Z.
X+Y→Z
The masses of X and Y are 5 gm and 6 gm respectively. The mass of Z _______ is gm.
According to the law of conservation of mass, the total mass before and after the reaction should be the same. So the mass of Z should be 11 gm i.e. 5 gm + 6 gm.