Chemical Engineering - Heat Transfer - Discussion

Correct, Agree @Milandangariya.

Mercury, because of boiling point is 356°C, at higher temperature mercury, is start to vaporized and it's vapour highly poisonous.

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More Cp (KJ/Kg K) value more will heat carrying capacity. Lower Cp value lesser will be the heat carrying capacity. Hg has less Cp value and high K( W/m K) value i.e.it carries less heat.

Mercury has lowest heat capacity among the options that is 0.14 J/gC which means that it requires a relatively very small amount of heat for temperature rise. So it is more heat sensitive and hence not used as a medium for high-temperature heating.

I think, due to high sensitivity of mercury towards heat.