I would appreciate it if someone could clarify whether these statements are true, 'the longer the chain length of the hydrocarbon, the less easily it combusts' and the longer carbon chain length the more energy that is released on combustion.
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Combustion and alkanes watch
- Thread Starter
- 31-05-2016 17:09
- Official Rep
- 02-06-2016 18:30
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Just quoting in Puddles the Monkey so she can move the thread if needed
Spoiler:Show(Original post by Puddles the Monkey)
- 02-06-2016 18:38
The first statement is correct as the longer the hydrocarbon chain, the more bonds there are between the hydrogen and carbon atoms. This means that for combustion to occur more bonds must be broken and more atoms reacted in a longer chain hydrocarbon, Therefore the longer the hydrocarbon chain, the harder it is to combust.
The second statement is also correct as the more bonds that are broken (more bonds in larger hydrocarbon) the more energy is released. As combustion is a exothermic reaction (it releases energy into the environment), the more bonds there are, the more energy is released. Therefore the longer the hydrocarbon chain, the more is released to the surroundings.
- 02-06-2016 18:39
- 03-06-2016 14:50
Yeah, more points of contact. More London forces, more energy required to combust.
If there is branching less points of contact, less London forces therfore easier to combust