The formation of CO and CO2 illustrates the law of multiple proportion. Let's understand this concept in detail:

Law of Multiple Proportion:
The law of multiple proportion states that when two elements combine to form more than one compound, the masses of one element that combine with a fixed mass of the other element are in the ratio of small whole numbers.

Explanation:
When carbon (C) and oxygen (O) combine, they can form two different compounds: carbon monoxide (CO) and carbon dioxide (CO2). By examining the masses of carbon and oxygen in these compounds, we can see that they follow the law of multiple proportion.

Formation of Carbon Monoxide (CO):
In carbon monoxide, one atom of carbon combines with one atom of oxygen. The molar mass of carbon is 12.01 g/mol, and the molar mass of oxygen is 16.00 g/mol. Therefore, the ratio of carbon to oxygen in CO is 12.01:16.00, which simplifies to 3:4. This ratio is a small whole number.

Formation of Carbon Dioxide (CO2):
In carbon dioxide, one atom of carbon combines with two atoms of oxygen. Using the same molar masses as before, the ratio of carbon to oxygen in CO2 is 12.01:32.00, which simplifies to 3:8. Again, this ratio is a small whole number.

Relation to the Law of Multiple Proportion:
Comparing the ratios of carbon to oxygen in CO (3:4) and CO2 (3:8), we can see that the masses of oxygen combined with a fixed mass of carbon (in this case, 3 g) are in the ratio of small whole numbers (4 and 8). This confirms the law of multiple proportion.

Significance:
The law of multiple proportion is an important concept in chemistry as it helps explain the relationship between the masses of elements in compounds. It provides evidence for the existence of fixed ratios in chemical reactions and supports the atomic theory.

In summary, the formation of carbon monoxide (CO) and carbon dioxide (CO2) illustrates the law of multiple proportion because the masses of oxygen combined with a fixed mass of carbon are in the ratio of small whole numbers.