Question

show that water illustrate law of constant proportion​

Answer 1

In a compound such as water the ratio of mass of hydrogen to the mass of oxygen is always 1:8. Thus, if 9 grams of water is decomposed 1 gram of hydrogen and 8 grams of oxygen are always obtained..

Answer 2

If pure samples of water are prepared from various sources and chemically analysed then it is found that

(a) The elements present in each sample are hydrogen and oxygen only.

(b) The ratio of weight of hydrogen to the weight of oxygen is 1 8.

Hence, water illustrates the law of constant proportions.