💯An Ingelious Way to Solve Mole Concept Combustion Questions

Mole Concept Combustion Questions

Here’s an “ingelious” way to solve combustion questions related to mole concept using model drawings (yep, like in primary school). Let’s look at a typical JC A Level H2 Chemistry question:

When 20 cm³ of a gaseous hydrocarbon were sparked with 150 cm³ of oxygen and the residual gases cooled to room temperature, a contraction of 60 cm³ occurred. A further contraction of 80cm³ took place when the residual gases were subjected to aqueous NaOH. Find formula of the hydrocarbon. [All gaseous volumes are measured under identical conditions.]