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Engineering
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Three thermochemical equations are given below

(i) C_{\left ( graphite \right )}+O_{2}\left ( g \right )\rightarrow CO_{2}\left ( g \right );

                                                             \Delta _{r} H^{o}=xkJmol^{-1}

(ii) C_{\left ( graphite \right )}+\frac{1}{2}O_{2}\left ( g \right )\rightarrow CO\left ( g \right );

                                                               \Delta _{r} H^{o}=ykJmol^{-1}

(iii) CO\left ( g \right )\frac{1}{2}O_{2}\left ( g \right )\rightarrow CO_{2}\left ( g \right );

                                                          \Delta _{r} H^{o}=zkJmol^{-1}

Based on the above equations, find out which of the relationship given below is correct?

  • Option 1)

    x=y-z

  • Option 2)

    z=x+y

  • Option 3)

    x=y+z

  • Option 4)

    y=2z-x

 
As we learnt in Hess's Law - The total amount of heat change in a chemical reaction is the same whether the reaction is carried  out in one or several steps by one or more methods. - wherein    According to Hest law, equation  (i) is sum of equation (ii) and (iii)   Option 1) x=y-z This option is incorrect  Option 2) z=x+y This option is incorrect  Option 3) x=y+z This option is...
Engineering
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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

 
  Enthalpy of combustion - Amount of Enthalpy change when 1 mole of substance is completly burn in excess of Oxygen - wherein         Total number of mole of   Total number of mole of    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
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