Which of the following is TRUE for alkanes?
Which of the following is TRUE for alkanes?
The correct options are
A Boiling point increases with increase in carbon content
B Melting point increases with increase in carbon content.
C The densities increase with increase in molecular masses.
D Alkanes are less reactive than alkenes and alkynes
Hydrocarbons are almost non-polar molecules. Therefore, the intermolecular forces of attraction are of van der Walls type, which mainly depends on the shape and, hence, on the structure of the molecule. These forces depend on the surface area of the contact between adjacent molecules. Greater the surface area, stronger is the van der Waals forces of attraction.
a. Boiling point: Boiling point increases with the increase in the carbon content due to the increase in surface area, and, hence, van der Waals forces of attraction and the boiling point increase.
Similarly the same with the melting point. Increase in carbon content makes an increase in melting point.
c. Density: Density increases with increase in molecular masses since density is mass per unit volume.
d. Reactivity of hydrocarbons: Since (C—C) and (C—H) bonds are quite strong, alkanes are the least reactive hydrocarbons. That is why they are called paraffins (Latin parum means little and affinis means affinity or reactivity).
A
Boiling point increases with increase in carbon content
B
Melting point increases with increase in carbon content.
C
The densities increase with increase in molecular masses.
D
Alkanes are less reactive than alkenes and alkynes
Hydrocarbons are almost non-polar molecules. Therefore, the intermolecular forces of attraction are of van der Walls type, which mainly depends on the shape and, hence, on the structure of the molecule. These forces depend on the surface area of the contact between adjacent molecules. Greater the surface area, stronger is the van der Waals forces of attraction.
a. Boiling point: Boiling point increases with the increase in the carbon content due to the increase in surface area, and, hence, van der Waals forces of attraction and the boiling point increase.
Similarly the same with the melting point. Increase in carbon content makes an increase in melting point.
c. Density: Density increases with increase in molecular masses since density is mass per unit volume.
d. Reactivity of hydrocarbons: Since (C—C) and (C—H) bonds are quite strong, alkanes are the least reactive hydrocarbons. That is why they are called paraffins (Latin parum means little and affinis means affinity or reactivity).
