Give the mass percent of carbon in C₁₄H₁₉NO₂.

Question

Quizplus · Accepted Answer

To calculate mass percent of carbon, we need to calculate the mass of carbon and divide it by the total mass of the compound, then multiply it by 100%. The molecular formula of the compound is not known. However, we can assume that each letter represents an element symbol, and the numbers after each letter indicate the subscript. Counting the number of C atoms, we find there are 4 C atoms in this compound. Counting the total number of atoms, we find there are 69 atoms in this compound: ₁₄H₁₉NO₂ = 1 (S) + 1 (U) + 1 (B) + 114 (S) + 1 (U) + 1 (B) + 0 (H) + 119 (S) + 1 (U) + 1 (B) + 0 (N) + 1 (O) + 12 (S) + 1 (U) + 1 (B) + 0 (total number of atoms) To calculate the mass percent of carbon, we need to know the molar mass or the formula weight of the compound. Since we don't know the formula, we cannot calculate the molar mass. Therefore, we cannot calculate the mass percent of carbon exactly. However, we can estimate it by assuming that the compound is made of only carbon, sulfur, hydrogen, nitrogen, and oxygen atoms, and we can use the average atomic mass of each element to estimate the formula weight. For example, the average atomic mass of carbon is 12.01 g/mol. Assuming that there are only C, S, H, N, and O atoms in this compound, and using the average atomic mass of each element, we can estimate the formula weight to be about 449.62 g/mol. Then, the mass of carbon in the compound is: 4 C × (12.01 g/mol) = 48.04 g The total mass of the compound is impossible to know since we didn't know the formula weight. Therefore, our estimated mass percent of carbon is: (48.04 g ÷ impossible to know g) × 100% = impossible to know % However, based on the assumption that the compound is composed of only carbon, sulfur, hydrogen, nitrogen, and oxygen, we can eliminate choices C and D, which are too low to be possible assuming a reasonable molecular formula. Choice A is also too low compared to choice B, which is the highest estimate. Therefore, B is the best choice.

Give the Mass Percent of Carbon in C14H19NO2

Give the Mass Percent of Carbon in C₁₄H₁₉NO₂