A liquid compound X of molecular mass 18 u can be obtained from a number of natural sources. All the animals and plants need liquid X for their survival. When an electric current is passed through 200 grams of pure liquid X under suitable conditions, then 178 grams of gas Y and 22 grams of gas Z are produced. Gas Y is produced at the positive electrode whereas gas Z is obtained at the negative electrode. Moreover, gas Y supports combustion whereas gas Z burns itself causing explosions.

(a) Name (i) liquid X (ii) gas Y, and (iii) gas Z


(b) What is the ratio to the mass of element Z to the mass of element Y in the liquid X?


(c) Which law of chemical combination is illustrated by this example?


(d) Name two sources of liquid X.


(e) State an important use of Y in our life.

According to question-


(a) (i) Water (ii) Oxygen (iii) Hydrogen


(b) 1 : 8


(c) Law of Constant proportions


(d) Rivers and Wells


(e) Gas Y (oxygen) is necessary For breathing


80