Question

arrange the molecules by the strength of the london (dispersion) force interactions between molecules. strongest london dispersion forces weakest london dispersion forces answer bank ch₃ch₂ch₂ch₂ch₃ ch₃c(ch₃)₂ch₃ ch₃ch₂ch₂ch₂ch₂ch₂ch₃

Explanation:

Step1: Understand London - dispersion force factor

London - dispersion forces increase with increasing molar mass and surface area. Larger molecules have more electrons, leading to stronger temporary dipoles. Also, straight - chain molecules have a larger surface area for contact compared to branched - chain molecules of the same molar mass.

Step2: Analyze molar mass

The molar masses of the given alkanes increase with the number of carbon atoms. The number of carbon atoms in $CH_3CH_2CH_2CH_2CH_3$ (pentane) is 5, in $CH_3C(CH_3)_2CH_3$ (2,2 - dimethylpropane) is 5, and in $CH_3CH_2CH_2CH_2CH_2CH_2CH_3$ (heptane) is 7. Heptane has the highest molar mass among them.

Step3: Analyze surface area

$CH_3CH_2CH_2CH_2CH_3$ is a straight - chain alkane, and $CH_3C(CH_3)_2CH_3$ is a branched - chain alkane. For alkanes with the same number of carbon atoms, the straight - chain alkane has a larger surface area. So, $CH_3CH_2CH_2CH_2CH_3$ has stronger London - dispersion forces than $CH_3C(CH_3)_2CH_3$.

Answer:

Strongest London dispersion forces: $CH_3CH_2CH_2CH_2CH_2CH_2CH_3$
Second - strongest: $CH_3CH_2CH_2CH_2CH_3$
Weakest London dispersion forces: $CH_3C(CH_3)_2CH_3$