1. Under certain atmospheric conditions, the temperature of the surrounding air rises as a snowfall begins, because energy is released to the stmosphere as water changes to snow. What is the enthalpy change delta H for the freezing of 1000kg of water at 0.0 degree C to 1000kg of snow at 0.0 degree C?
delta H=(delta H(fusion))(n)=(6.03)(55493.896)
But according to my text book, "enthalpy changes for exothermic rxn are given a negative
sign and enthalpy changes for endotheermic rxn are given a positive sign..." The trouble is the textbook has a positive answer(maybe wrong...)
So should the answer be negative, ie -3.35x10^5kJ?
If so, which part in the calculation did I do wrong? (I get a positive)
Molar enthalpy of fusion of H2O=6.03
would freezing make this value negative? But my teacher says this is always positive, no matter melting or freezing...I am confused...
Please help me! Thank you!