Question

7 multiple choice 1 point which of the molecules has the highest boiling point? liquid 1: ch4 liquid 3: ch3ch2ch3 liquid 4: ch3ch2ch2ch3 liquid 2: ch3ch3 clear my selection previous

Explanation:

Step1: Intermolecular forces

For non - polar hydrocarbons (all these are alkanes, non - polar), the main intermolecular force is London dispersion force.

Step2: Relationship between molar mass and London dispersion force

The strength of London dispersion force increases with the increase in molar mass (or the number of electrons in the molecule).
The molar masses:

• \(CH_4\) (Liquid 1): \(M = 16\space g/mol\)
• \(CH_3CH_3\) (Liquid 2): \(M=(2\times12 + 6\times1)=30\space g/mol\)
• \(CH_3CH_2CH_3\) (Liquid 3): \(M=(3\times12+8\times1) = 44\space g/mol\)
• \(CH_3CH_2CH_2CH_3\) (Liquid 4): \(M=(4\times12 + 10\times1)=58\space g/mol\)

Step3: Relationship between boiling point and intermolecular force

Since boiling point is related to the strength of intermolecular forces (higher intermolecular force requires more energy to separate the molecules), and Liquid 4 (\(CH_3CH_2CH_2CH_3\)) has the highest molar mass among the given alkanes, it has the strongest London dispersion force and thus the highest boiling point.

Answer:

Liquid 4: \(CH_3CH_2CH_2CH_3\)