# Law of Multiple Proportions

## Main Question or Discussion Point

If X and Y represent atoms of different elements, as described in I, which descriptions II - IV represent the law of multiple proportions?

I: 4 X atoms and 12 Y atoms are spotted

II: 4 molecules; each are comprised of 1 X atom and 3 Y atoms
III: 4 molecules; each are comprised of 1 X atom and 2 Y atoms
IV: 2 sets of diatomic molecules are spotted; 2 diatomic molecules of X and 6 diatomic molecules of Y

a. only descriptions II and IV
b. descriptions II, III, IV
c. only descriptions III and IV
d. only descriptions II and III

Is the correct choice d. II and III? (Am I supposed to look at the numbers of element to determine if the mass ratios are whole numbers of each other?)

Thanks.

GCT
Homework Helper
first, state the law of multiple proportions

"If two elements form more than one compound between them, then the the ratios of the weights of the second element which combine with a fixed mass of the first element will be ratios of small whole numbers."

Gokul43201
Staff Emeritus