Question

An element forms two oxides of `2.900 g` and `2.250 g` of these oxides each of found to contain `1.12 L` of `O_(2)` at `STP`. Which law of chemical combination is illustrated by these data?

Answer 1

According to gram molecular volume law, `22.4 L` of all gaese at `STP` weigh equal to their molecular weights denoted in grams. Hence, the weight of `1.12 L` of oxygen at `STP`
`(32 xx 1.12)/(22.4) = 1.600 g`
In the first oxide:
Weight of oxide `= 2.900 g`, weight of `O_(2) = 1.600 g`
`:.` Weight of the element `= 2.900 - 1.600 = 1.300 g`
In the other oxide:
Weight of oxide `= 2.250 g`, weight of `O_(2) = 1.600 g`
Weight of element `= 2.250 - 1600 = 0.650 g`
Thus, the weights of the element that combine with the same weight of oxygen in its two oxides are in the ratio of `1.3 : 0.065` or `2 : 1` a simple ratio. hence, it illustrates the law of multiple proportions.