1.

Heat of formation of SO_(2) is -298 kJ. What is the heat of combustion of 4 g of S?

Answer»

`+37kJ`
`-37.25 kJ`
`+298kJ`
`18.6kJ`

Solution :Heat of combustion is TOTAL heat changes accompanying when ONE mole of substance undergoes complete combustion in EXCESS of oxygen.
`S+O_(2) to SO_(2),DeltaH=298kJ`
`therefore`Heat of formation of `SO_(2)`=heat of combustion of `SO_(2)` atomic mass of S=32G
`because`Combustion of 32g of S(=1 mole of S) gives heat
=-298 kJ
`therefore `Combustion of 4g of S gives heat`=(-298)/(32)xx4=-37.25kJ`.


Discussion

No Comment Found

Related InterviewSolutions