Q6 of 16 Page 57

Two samples ‘m’ and ‘n’ of slaked lime were obtained from two different reactions. The details about their composition are as follows:

‘sample m’ mass: 7g


Mass of constituent oxygen: 2g


Mass of constituent calcium: 5g


‘sample n’ mass: 1.4g


Mass of constituent oxygen: 0.4g


Mass of constituent calcium: 1.0g


Which law of chemical combination does this prove? Explain.

Slaked lime = calcium hydroxide {Ca(OH)2}


The law of constant proportions states that “The proportion by weight of the constituent elements in the various samples of a compound is fixed,”


The proportion by weight of oxygen and calcium in slaked lime(in sample m) is 2:5 i.e. 0.4:1


The proportion by weight of oxygen and calcium in slaked lime(in sample n) is 0.4:1.0


Since the proportions of constituent elements remain fixed it follows the law of constant proportion.


More from this chapter

All 16 →