13 Halogenoalkanes

Question 1

What is bondpolarity of halogenoalkanes ?

Answer 1

•carbon has a slight positive
•halogen has a slight negative as it’s more electronegative
•as you go down the group the bonds get less polar

Question 2

What are physical properties of halogenoalkanes ?

Answer 2

•insoluble in water
•intermolecular forces are dipole dipole and van der Waals
•can be mixed with th hydrocarbons to make dry cleaning fluids

Question 3

What are the boiling points of halogenoalkanes ?

Answer 3

•BP increases with chain length
•BP increase as you go down halogen group
•effects caused by increase of van der Waals force

Question 4

How do halogenoalkanes react?

Answer 4

•C-Halogen bond always break and factors that effect it are
Bond polarity
Bond enthalpy

Question 5

How does bond polarity affect the reactivity of a halogenoalkanes?

Answer 5

•carbon bonded to halogen has a slight positive charge (electron deficient )
•can be attacked by nucleophiles (reagents that are electron rich /electron pair donor)

Question 6

What are nucleophiles ?

Answer 6

•reagents that attach and form bonds with positive or partially positively charged carbon atoms

Question 7

What are the different nucleophiles ?

Answer 7

•negatively charged in or has an atom with a slight negative charge
•lone pair of electrons which can form a covalent bond

Question 8

What are common nucleophiles

Answer 8

Hydroxide ion -•OH
Ammonia -••NhH3
Cyanide ion -••CB

Question 9

What are nucleophilic substitutions?

Answer 9

•nucleophiles replace a halogen in a halogenoalkanes