halogenoalkanes Flashcards
what are halogenoalkanes
halogenoalkanes are organic compounds where the hydrogen atom on an alkane has been replaced by a halogen atom
What are the inductive effects of alkyl groups?
- Alkyl groups are electron donating groups
- they push electrons towards the carbon that the group is bonded to. Making the alkyl group have a slight positive charge and the carbon it is bonded with to have a slight negative charge. This is called the positive inductive effect
What are the relative strengths of carbon-halogen bonds?
As you go down group 7, the carbon-halogen bond strength decreases: c-f > c-cl>c-br>c-I
What is the trend in the rate of hydrolysis of carbon-halogen bonds?
As you go down the group, the rate of hydrolysis of carbon-halogen bonds increases as less energy is required to break the bond, since bond strength weakens down the group
What are the uses of fluoro alkanes and fluorohalogenoalkanes
-Refrigerants
-Used in aerosols
- used in making foamed plastics
They are chemically inert and will not react with anything
chemical test for halogenoalkane
- react with AgNO3(aq) and test the solubility of the precipitate in NH3(aq)
- AgCl- white ppt, soluble in dilute NH3
- AgBr- cream ppt, soluble in concentrated NH3
- AgI-yellow ppt, insoluble in NH3
chemical test for carboxylic acid
react with a carbonate. If a carboxylic acid is present, CO2 will be produced and so the solution will effervesce