Per NCERT Table 5.1, the standard enthalpies of fusion and vaporisation of WATER are which?
AΔfus 6, Δvap 6
BΔfus 100, Δvap 1000
CΔfus H° = 6.01 kJ/mol (at 273.15 K); Δvap H° = 40.79 kJ/mol (at 373.15 K)
DΔfus 40, Δvap 6
Answer & Solution
Correct answer: C. Δfus H° = 6.01 kJ/mol (at 273.15 K); Δvap H° = 40.79 kJ/mol (at 373.15 K)
Per NCERT Table 5.1, H₂O: Δfus = 6.01 kJ/mol, Δvap = 40.79 kJ/mol. Both positive (endothermic).
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