BIOCHEMISTRY
ISOMERS
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
Alkynes have the smallest molecular mass
|
|
|
The electronegativity of alkynes are higher than alkenes and alkynes
|
|
|
Alkynes have the highest molecular size
|
|
|
Alkynes have 1 pi bond and 2 sigma bond
|
|
|
Van der walls force of alkynes are smaller than alkanes and alkenes
|
Detailed explanation-1: -The sp hybridised alkyne has more s character in comparison to alkene and alkane. Therefore the pi electrons are more tightly held in alkynes due to more electronegativity. This gives rise to small dipole moment in alkynes. Hence they are polar.
Detailed explanation-2: -The alkynes are more electronegative due to the presence of more character. Hydrogen atoms can therefore be liberated as protons more readily in Ethyne. Hence, alkynes are more acidic than alkanes and alkenes.
Detailed explanation-3: -Solution : They are all basically ninpolar but alkynes are relatively more polar on account of more polarzation of their ‘pi‘-electrons. Thus, alkynes are slightly more soluble in water than alkenes and alkanes.
Detailed explanation-4: -The triple bonds of alkynes, because of its high electron density, are easily attacked by electrophiles, but less reactive than alkenes due to the compact C-C electron cloud.As with electrophilic addition to unsymmetrical alkenes, the Markovnikov rule is followed, adding the electrophile to the less substituted carbon.
Detailed explanation-5: -Alkenes are those hydrocarbons that contain at least one − bond while the alkanes contain only sigma bonds. Since sigma bonds are stronger than − bonds. Therefore, alkenes are more reactive than alkanes.