Skeletal Structure Practice Problems

Make a model of n-butane (C₄H₁₀), and use wedges and dashed lines to represent bonds coming forward and going back respectively to draw the model of n-butane.

A scientist was able to isolate a few miligrams of pure testosterone, a primary sex hormone in males. When the scientist burned 5.00 mg of the testosterone sample he had isolated in oxygen, he found that 14.496 mg of CO₂ and 4.373 mg of H₂O were generated in the chemical reaction. Determine the molecular formula of testosterone if the molecular weight analysis showed that the molecular weight of testosterone is 288 g/mol.

Compound A is a compound found in goat's milk. A careful analysis showed that compound A contains 42.11% carbon and 6.48% hydrogen. No nitrogen or halogen was found. Determine the molecular formula of compound A if molecular weight analysis showed that compound A has a molecular weight of about 342 g/mol.

Give a molecular formula that corresponds to each of the following structures. 

If possible, draw a stable structure for each molecular formulas of hydrocarbons shown below. Make a generalization for the numbers of hydrogen atoms in stable hydrocarbons.

C₄H₄  C₄H₅  C₄H₆  C₄H₇  C₄H₈  C₄H₉  C₄H₁₀  C₄H₁₁

C₅H₄  C₅H₅  C₅H₆  C₅H₇  C₅H₈  C₅H₉  C₅H₁₀  C₅H₁₁  C₅H₁₂