Question

40 ml of methane is completely burnt using 80 ml of oxygen at room temperature. The volume of gas left after cooling to room temperature is
(a) 40 ml CO2 gas
(b) 40 ml CO2 gas and 80 ml H2O gas
(c) 60 ml CO2 gas and 60 ml H2O gas
(d) 120 ml CO2 gas

Answer 1

The balanced chemical equation is:


CH4 + 2 O2 = CO2 + 2 H2O


From the equation, we can see that:

1 vol CH4 react with 2 vol O2 to produce 1 vol CO2 and 2 vol H2O


If 40 ml of methane is completely burnt using 80 ml of oxygen, then 40ml of CO2 and 80ml of H2O (Vapour) will be formed.


When cooled to room temperature, only 40ml of CO2 gas will remain because water will be in liquid form. 

(a) 40 ml CO2 gas 

Answer 2

The correct answer is option is a. 40 ml of CO2 gas