# On burning hydrogen in an atmosphere of chlorine, 1.65 gm of HC1 was obtained and 1 Kcal of heat was liberated. The heat of formation of HC1 should be ?

-21.12 Kcal $mo{l}^{-1}$

-44.2 Kcal $mo{l}^{-1}$

500 cal $mo{l}^{-1}$

500 cal $g{m}^{-1}$

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