A compound containing only C, H, and O, was extracted from the bark of the sassa

Question

A compound containing only C, H, and O, was extracted from the bark of the sassafras tree. The combustion of 83.3 mg produced 226 mgof Co2 and 46.3 mg of H20.The olar mass of the compound was 162 g/mol. Determine its empirical and molecular formulas. 1st attempt Part 1 (0.5 point) See Periodic Table Note that formulas of organic compounds should first list the carbon and hydrogen with the rest of the atomslisted in alphabetical order. For this problem use the format CHyOz where x, y and z are subscripts of 2 or greater Empirical Formula: Part 2 (0.5 point) See Hint Molecular Formula:

Explanation / Answer

Part 1

Number of moles of C = CO2 = 0.226 / 44.01 = 0.005 moles

Mass of carbon = 12.001 x 0.005 = 0.06 g or 60 mg

Number of moles of water = 0.0463 / 18.0152 = 0.0026 moles

number of moles of H atoms in compound = 2 x 0.0026 = 0.0052 moles

Mass of hydrogen = 0.0052 x 1.008 = 0.0052 g or 5.2 mg

Mass of oxygen in sample = 83.3 - (60 + 5.2)

= 18.1 mg

Number of moles of oxygen = 0.0181/16 = 0.0011 moles

The ratio of atoms in empirical formula becomes : 5 : 5 : 1

So the empirical formula becomes : C5H5O

Part 2 :

the empirical mass = ( 12.001 x 5) + ( 1.008 x 5) + 16

= 81 g/mol

molecular mass / empirical mass = 162/81 = 2

multiply empirical formula by 2 to get molecular formula

So the molecular formula will be :

C10H10O2

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