According to the **Law of Multiple Proportions**, when two elements (A & B) form different compounds, the masses of element B that combine with 1 g of A are a **ratio of whole numbers**.

$\mathbf{mass}\mathbf{}\mathbf{ratio}\mathbf{}\mathbf{A}\mathbf{=}\frac{\mathbf{1}\mathbf{.}\mathbf{836}\mathbf{}\overline{)\mathbf{g}}\mathbf{}\mathbf{O}}{\mathbf{1}\mathbf{}\overline{)\mathbf{g}}\mathbf{}\mathbf{C}}\mathbf{=}\mathbf{1}\mathbf{.}\mathbf{836}\phantom{\rule{0ex}{0ex}}\mathbf{mass}\mathbf{}\mathbf{ratio}\mathbf{}\mathbf{B}\mathbf{=}\frac{\mathbf{3}\mathbf{.}\mathbf{672}\mathbf{}\overline{)\mathbf{g}}\mathbf{}}{\mathbf{1}\mathbf{}\overline{)\mathbf{g}}}\mathbf{=}\mathbf{3}\mathbf{.}\mathbf{672}$

When carbon and oxygen react, two different compounds can form depending on the conditions. Compound A contains 1.836 g of oxygen per gram of carbon, whereas compound B contains 3.672 g of oxygen per gram of carbon.

If compound A has an equal number of oxygen and carbon atoms, what can we conclude about the composition of compound B?

(a) It has half as many oxygen than carbon atoms.

(b) It has twice as many oxygen than carbon atoms.

(c) It has an equal number of oxygen and carbon atoms.

Frequently Asked Questions

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Atomic Theory concept. You can view video lessons to learn Atomic Theory. Or if you need more Atomic Theory practice, you can also practice Atomic Theory practice problems.