Compound X, isolated from lanolin (sheep's wool fat), has the pungent aroma of dirty sweatsocks. A careful analysis showed that compound X contains 62% carbon and 10.4% hydrogen. No nitrogen or halogen was found.

a. Compute an empirical formula for compound X.

Express your answer as a condensed structural formula.

b. A molecular weight determination showed that compound X has a molecular weight of approximately 117. Find the molecular formula of compound X.

Express your answer as a condensed structural formula.

Respuesta :

Answer:

The empirical formula of compound X [tex]C_3H_{6}O_1[/tex].

The molecular formula of compound X [tex]C_6H_{12}O_2[/tex].

Explanation:

Compound X contains 62% carbon and 10.4% hydrogen.Suppose in 100 g of compound 62 grams of carbon ,10.4 grams of hydrogen  is present and 27.6 grams.

Moles of carbon = [tex]\frac{62 g}{12 g/mol}=5.17 mol[/tex]

Moles of hydrogen = [tex]\frac{10.4 g}{1 g/mol}=10.4 mol[/tex]

Moles of oxygen = [tex]\frac{27.6 g}{16 g/mol}=1.725 mol[/tex]

For empirical formula divide the smallest number of moles of from all the moles of element:

For carbon = [tex]\frac{5.17 mol}{1.725 mol}=3[/tex]

For hydrogen = [tex]\frac{10.4mol}{1.725 mol}=6[/tex]

For oxygen = [tex]\frac{1.725 mol}{1.725 mol}=1[/tex]

Empirical formula for compound X :[tex]C_3H_6O[/tex]

The empirical formula of compound X [tex]C_3H_{6}O_1[/tex].

Empirical mass for compound X :

=[tex]3\times 12 g/mol+6\times 1g/mol+1\times 16 g/mol =58 g/mol[/tex]

Molecular mass of the compound X = 117 g/mol

[tex]\text{Moleculare mass}=n\times \text{Empirical mass}[/tex]

[tex]117 g/mol=n\times 58 g/mol[/tex]

[tex]n=\frac{117 g/mol}{58 g/mol}=2.0[/tex]

Molecular formula for compound X :[tex]C_{n\times 3}H_{n\times 6}O_{n\times 1}=C_6H_{12}O_2[/tex]

The molecular formula of compound X [tex]C_6H_{12}O_2[/tex].