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Butane has the formula C4H10. Calculate the mass of carbon in 100g of butane, giving your answer to three significant figures.

A) 11.5 g
B) 12.0 g
C) 48.0 g
D) 120 g

User Arma
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1 Answer

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Final answer:

To find the mass of carbon in 100g of butane, calculate the percentage of the total molar mass attributed to carbon and then apply that percentage to the 100g. The resulting mass of carbon in 100g of butane is approximately 82.6 g, which suggests an error in the provided options.

Step-by-step explanation:

The question asks to calculate the mass of carbon in 100g of butane (C4H10). To do this, we first calculate the molar mass of butane. Carbon (C) has an atomic mass of 12.01 g/mol and hydrogen (H) has an atomic mass of 1.01 g/mol. The molar mass of butane is calculated as follows:

  • (4 C atoms) x (12.01 g/mol) = 48.04 g/mol for C
  • (10 H atoms) x (1.01 g/mol) = 10.10 g/mol for H
  • Total molar mass of C4H10 = 58.14 g/mol

Next, we find the percentage of carbon in butane by weight:

Percentage of C = (Mass of C in the formula / Molar mass of C4H10) x 100

Percentage of C = (48.04 g/mol / 58.14 g/mol) x 100 ≈ 82.59%

Finally, we calculate the mass of carbon in 100 g of butane:

Mass of carbon = (Percentage of C / 100) x Mass of butane

Mass of carbon ≈ 82.59% x 100g ≈ 82.6 g

The mass of carbon in 100g of butane is approximately 82.6 g, so the correct answer is not among the options given (A, B, C, D).

User Matthew Snell
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