The Society of Automotive Engineers has established an accepted numerical scale to measure the viscosity of motor oil. For example, SAE 40 motor oil has a higher viscosity than an SAE 10 oil.

Rank the following hydrocarbons by their expected viscosity.
Rank from most to least viscous.


a. CH3CH2CH2CH2CH2CH3
b. CH3CH2CH2CH2CH2CH2CH2CH3
c. CH3CH2CH2CH2CH2CH2CH2CH2CH2CH3

Respuesta :

Because its molecules can slide around each other, a liquid has the ability to flow. The resistance to such flow is called the viscosity. For organic liquids, as the chain increases the viscosity increases as well due to the bonding that is present. Therefore, the ranking should be as follows:

CH3CH2CH2CH2CH2CH2CH2CH2CH2CH3
CH3CH2CH2CH2CH2CH2CH2CH3 
CH3CH2CH2CH2CH2CH3 

Explanation:

Viscosity is defined as the ability of a liquid substance to oppose its flow. So, more is the mass of a liquid more will be its viscosity.

Since, the given option of hydrocarbons show different compounds. And, longer is the chain of hydrocarbon more will be its mass.

As a result, more difficulty it will face to flow. Therefore, it means greater will be the viscosity of hydrocarbon that has longer chain of carbon and hydrogen atoms.

Thus, we can conclude that given hydrocarbons are ranked from most to least viscous as follows.

[tex]CH_{3}CH_2CH_2CH_2CH_2CH_2CH_2CH_2CH_2CH_3[/tex] > [tex]CH_3CH_2CH_2CH_2CH_2CH_2CH_2CH_3[/tex] > [tex]CH_3CH_2CH_2CH_2CH_2CH_3[/tex]