Get Answers to all your Questions

header-bg qa

When 5 litres of a gas mixture of methane and propane is perfectly combusted at 0o C and 1 atmosphere, 16 litre of oxygen at the same temperature and pressure is consumed. The amount of heat released from this combustion in kJ (\Delta H_{comb}(CH_4))= 890 \:\:kJ\:\:mol^{-1}, \:\: \Delta H_{comb}(C_3H_8)=2220\: kJ\: mol^{-1}) is

  • Option 1)

    32

  • Option 2)

    38

  • Option 3)

    317

  • Option 4)

    477

 

Answers (1)

 

Enthalpy of combustion -

Amount of Enthalpy change when 1 mole of substance is completly burn in excess of Oxygen

-

wherein

CO_{(g)}+\frac{1}{2}O_{2}(g)\rightarrow CO_{2(g)}+283\ KJ

\Delta H_{comb} \: of\: CO= 283\, KJ

 

 CH_4+2O_2\rightarrow CO_2+2H_2O

 

C_3H_8+5O_2\rightarrow 3CO_2+4H_2O

 

Total number of mole of CH_4+C_3H_8= \frac{5L}{22.4L}=0.22 

Total number of mole of O_2O_2= \frac{0.16}{22.4}= 0.71 mol

 

2x+(0.22-x)5= 0.71

\therefore x= 0.13

Heat liberated = 0.13*890+0.09*2220= 317 kJ


Option 1)

32

Incorrect option

Option 2)

38

Incorrect option

Option 3)

317

Correct option

Option 4)

477

Incorrect option

Posted by

Sabhrant Ambastha

View full answer

Similar Questions