HALO GROUP ( ALKYL HALIDE )
PROPERTIES
This tends to be insoluble in water ( similar to alkanes)
Compounds with many fluorine atoms tend to be unreactve ( "inert" )
"Teflon" is a highly fluorinated hydrocarbon which is inert to almost all chemical attack
Chloro and bromo compounds are susceptible to chemical attack, but require relatively drastic conditions
- Iodo compounds are more reactive
Compounds with many fluorine atoms tend to be unreactve ( "inert" )
"Teflon" is a highly fluorinated hydrocarbon which is inert to almost all chemical attack
Chloro and bromo compounds are susceptible to chemical attack, but require relatively drastic conditions
- Iodo compounds are more reactive
DIAGRAMS
HOW TO SHOW HALO GROUPS?
- the steps of naming Alkyl groups is same as naming Alkanes, but there are more atoms to name
- Here are four steps to follow
Step 2. Fine the name of branches which are different atoms
; such as F ( fluoro ), Cl ( chloro ), Br ( bromo ) or I ( iodo )
Step 3. Use a number to indicate the position of attachment on the hydrocarbon chain
- If more than one of the same kind of halogen is present, use the prefixes di, tri, etc.
- If a compound contains both Alkyl and Halo groups, list the attached groups in alphabetical order
Step 4. Start numbering from the end which gives the lowest set of numbers
EXAMPLES
- Here are three examples to name Halo groups
ex 1) CH3 - Cl : chloromethane
ex 2) CCl3 - CF3 : 1,1,1-trichloro-2,2,2-trifluoroethane
ex 3) CH2F - CHCl2 : 1,1-dichloro-2-fluoroethane
- Here are two examples to draw Halo groups
fluorocyclopentane
1-iodo-4-methylpentane
PRACTICE QUESTIONS
- Here are three practice questions to name Halo groups
Q 1)
Q 2)
Q 3)
- Here are two practice questions to draw Halo groups
Q 4) 1,1-dichloro-2-ethylcyclohexane
Q 5) trichloromethane ( common name is chloroform)
ANSWERS
Q 1) chloroethane
Q 2) 2,2-dibromo-3-methylhexane
Q 3) 4-bromo-2-chloro-3-ethyloctane
Q 4)
Q 2) 2,2-dibromo-3-methylhexane
Q 3) 4-bromo-2-chloro-3-ethyloctane
Q 4)
Q 5) CHCl3
EXAMPLES IN EVERYDAY LIFE
Refrigerator
Fire extinguisher
Fire extinguisher