The law of definite proportion asserts that the proportions of each element in relation to its weight will constantly be the exact value in a chemical combination, regardless of the amount or source.
In the given question:
The sample of chemical X has:
The total mass number of the compound = (10.0 + 5.0 + 20.0) g
= 35.0 g
The fraction of Carbon in the compound is;
[tex]=\dfrac{10}{35} \\ \\ \mathbf{= \dfrac{2}{7}}[/tex]
Thus, the mass of carbon (grams) in 61 grams of the sample is;
[tex]= \dfrac{2}{7}\times 61[/tex]
= 17.42 grams
≅ 17 grams
Therefore, we can conclude that a 61-gram sample of chemical x should contain 17 grams of carbon.
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