Because matter cannot be created or destroyed
Solid, Liquid, and Gas
Solid is the state in which matter maintains a fixed volume and shape; liquid is the state in which matter adapts to the shape of its container but varies only slightly in volume; and gas is the state in which matter expands to occupy the volume and shape of its container.
2AgCl (s) + Ba(NO3)2 (aq)
Communication will be the answer
A base and an Acid always react to form a salt and water
So, HCl + NaOH —> NaCl + HOH