"3.4 I can recall the products of complete and incomplete combustion of alkenes"

1.       Saturated hydrocarbons are called Alkane

2.       Small chain Alkanes are used as fuels

3.       The reaction is called combustion

4.       The word equation for  this chemical reaction is :

fuel (alkane) + Oxygen→ Water + Carbon dioxide + ENERGY (heat, light, sound)

5.       If there is insufficient oxygen then the word equation is:

fuel (alkane) +Oxygen → Water+ Carbon monoxide + ENERGY (heat, light, sound)

6.       The problem with this reaction is that carbon monoxide is produced this gas is a threat to the human body (see objective 5.11)

7.       Where can you find incomplete combustion? In cars

8.       What is used to reduce the harmful products from incomplete combustion? catalytic converter (converts carbon  monoxide --> Carbon dioxide)

9.       During incomplete combustion a smoky flame is often seen, explain this observation

The smoke is the unburnt carbon in the incomplete combustion  which forms soot.

Extn: write a balanced equation (with state symbols) for the combustion of propane gas

C3H8(g) + 5O2(g) → 3CO2(g) + 4H2O(l)