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Flashcards in alkanes Deck (10)
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1
Q

general formula for alkanes

A

CnH2n+2

2
Q

how are sigma bonds formed?

A

overlap of 2 orbitals, for each bonding atom

3
Q

what are the bond angles of alkanes?

A

109.5

4
Q

what is the shape from alkanes?`

A

tetrahedral

5
Q

explain the effect of chain length of boiling point.

A
  • as the chain length increases
  • surface area increases
  • greater surface area of contact
  • London forces increases
  • more energy is needed to overcome the forces
  • boiling point increases
6
Q

explain the effect of branching on boiling point

A
  • more branching
  • decrease in surface area of contact
  • London forces increases
  • less energy is needed to overcome the forces
  • boiling point decreases
7
Q

explain why alkanes do not react with most common reagents.

A
  • sigma bonds are strong
  • C-C bonds are non- polar
  • C-H bonds are non- polar
  • electronegativity of carbon and hydrogen are similar
8
Q

write the equation for the complete combustion of alkanes

A

alkane + oxygen -> carbon dioxide + water

9
Q

write the equation for the incomplete combustion of alkanes

A

alkane + oxygen -> carbon monoxide/ carbon + water

10
Q

explain the limitations of radical substitution in organic synthesis

A
  • further substitution resulting in a mixture of compounds being formed
  • Substitution at different positions in a carbon chain