1·7 g of silver nitrate is dissolved in 100 g of water, and 0·585 g of sodium chloride is dissolved in 100 g of water. Both are mixed and a chemical reaction occurs. 1·435 g of silver chloride and 0·85 g of sodium nitrate are formed. Which law of chemical combination is shown by the above reaction?

Total mass of reactants = 1.7 g (AgNO3) + 0.585 g (NaCl) = 2.285 g. Total mass of products = 1.435 g (AgCl) + 0.85 g (NaNO3) = 2.285 g. Since the mass before and after the reaction is exactly equal, this illustrates the Law of Conservation of Mass, which states that matter is neither created nor destroyed in a chemical reaction. The other laws (multiple, reciprocal, constant proportions) relate to mass ratios of elements in compounds, not the equality of reactant and product masses.