Chemical Properties of Carbon Compounds:
- It is the process of burning carbon compounds in the presence of oxygen ( air) to release CO 2 and energy in the form of heat and light.
- Combustion is also known as burning.
- Alkanes are very good fuels because when they burn in air, they produce a lot of energy. For example, methane CH 4 is a component of natural gas .
- When methane burns in abundance of oxygen (sufficient supply of air), complete combustion takes place to produce CO 2 , H 2 O and energy.
- The saturated hydrocarbons usually burn in air with a blue, non-sooty flame i.e. complete combustion takes place. But if they are burnt in limited oxygen supply, incomplete combustion takes place ( a yellow and sooty flame is produced).
- On the other hand, unsaturated hydrocarbons burn in air to produce a yellow sooty flame . However, if they are burnt in pure oxygen, complete combustion takes place.
2. Substitution Reaction :
- These are the reactions in which one or more hydrogens of a hydrocarbon are replaced by some other atoms like chlorine .
- Substitution reactions are a characteristic property of Saturated hydrocarbons which are otherwise quite unreactive due to the presence of only C-C single bonds , but they are able to undergo substitution reactions.
E.g. Chlorination of methane
3. Addition Reaction:
- These reactions involve the addition of one or more hydrogen atoms to double/triple bonds .
- Therefore, this is a characteristic reaction of unsaturated hydrocarbons . Saturated hydrocarbons don’t show addition reactions.
- For example, hydrogenation reactions .
Note: In this reaction Pd/C acts as a catalyst i.e. a substance to speed up the reaction.