Question

When 50 cm³ of hydrocarbon Y is burnt, it reacts with exactly 300 cm³ of oxygen to form 200 cm³ of carbon dioxide. Water is also formed in the reaction. Deduce the equation for this reaction. Explain your reasoning.

Answer 1

15 x 23.5(16.9)•{2yx}

Answer 2

Answer:

C2H4 + 3O2---> 2CO2 + 2H2O

Explanation:

The volume of the gas is directly proportional to the no. of moles of the gas at constant temperature and pressure.

So Volume of O2 : Volume of CO2 = 300: 200

= 3:2

So we can add 3 and 2 stoichiometric coefficients to O2 and CO2 respectively.

Then we can see that out of total 3×2 atoms of O, 2×2 atoms of O have been incorporated into CO2. Therefore the remaining 2 O should be in the H2O ( during complete combustion of hydrocarbon we get CO2 and H2O as products)

So we can add 2 in front of H2O..

Then calculate the total no. of C and H atoms in the products side to find the no. of C and H atoms in the hydrocarbon.

C=2

H=4

So the hydrocarbon burnt has the formula C2H4.