Sodium chloride ($NaCl$) reacts with silver nitrate ($AgN{O}_3$) to produce silver chloride ($AgCl$) and sodium nitrate ($NaN{O}_3$). The law which satisfies this equation is ___________________ .

The correct option is A conservation of mass
Reaction:

$NaCl+AgN{O}_3\to AgCl+NaN{O}_3$

Mol : 1 mol 1 mol 1 mol 1 mol

Mass : 58.5 g 170 g 143.5 g 85 g

Total mass of reactants is equal to the total mass of products. This is the law of conservation of mass.