Laws Of Chemical Combinations

The law of multiple proportions states that when two elements combine to form more than one compound, the masses of one element that combine with a fixed mass of the other element are in simple whole number ratios.

NO and NO : Nitrogen combines with oxygen to form NO and NO , and the ratio of oxygen in these two compounds follows the law of multiple proportions.

CuO and Cu O: Copper combines with oxygen to form these two compounds, and the mass of oxygen in CuO and Cu O follows the law of multiple proportions.

FeO and Fe O : Iron combines with oxygen in different proportions to form FeO and Fe O , which also follows the law of multiple proportions.

H O and H S: Water and hydrogen sulfide do not illustrate the law of multiple proportions because both compounds contain hydrogen in the same amount (2 atoms of H) but different non-metals (oxygen and sulfur), which doesn’t follow the rule of simple whole number ratios of mass.

Thus, H O and H S do not illustrate the law of multiple proportions.

The correct option is (D) : H₂O and N₂S