Important Questions on Combustion and Flame Distinguish between combustible and non-combustible substances, giving three examples of each. Why is it more difficult to burn some combustible substances than others? State the conditions under which combustion occurs. Why is more care needed to store kerosene than coal, though both are fuels? What problem will arise if a fuel has an ignition temperature lower than the average room temperature? Name the type of combustion that will occur in such a case. Why is water not suitable for extinguishing a fire in an electrical appliance? Name and give chemical equations to show the products of the combustion reaction in 
