Total heat evolved by reaction of
H2(g) and CO(g) is:
(241.8 + 283) kJ = 524.8 kJ
(by Hess's law)
Now volume occupied by a gas at STP is 22.4 L.
Volume of H2(g) = volume of CO(g) = 112/2 L= 56 L
Therefore , number of moles of each gas = 56/22.4 = 2.5 moles
Heat evolved by reaction of one mole of each gas = 524.8 kJ
Therefore , heat evolved by reaction of 2.5 moles of each gas = 524.8 *2.5 = 1312 kJ
Hence , option (c) is correct.
Heat evolved by reaction of one mole of each gas = 524.8 kJ