# CHEMISTRY

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Given that the specific heat capacities of ice and steam are 2.06 J/g°C and 2.03 J/g°C, the molar heats of fusion and vaporization for water are 6.02 kJ/mol and 40.6 kJ/mol, respectively, and the specific heat capacity of water is 4.18 J/g°C, calculate the total quantity of heat evolved when 25.6 g of steam at 194°C is condensed, cooled, and frozen to ice at -50.°C.

• CHEMISTRY -

It's best to work this in stages.
q1 = heat released in moving steam from 194 C to 100 C.
q1 = mass x specific heat steam x (Tfinal-Tinitial)

q2 = heat released to condense steam at 100 C to liquid water at 100 C.
q2 = mass steam x heat vaporixation.

q3 = heat released to move T of liquid water from 100 C to zero C.
q3 = mass x specific heat water x (Tfinal-Tinitial).

q4 = heat released to freeze water at zero C to ice at zero C.
q4 = mass water x heat fusion.

q5 = heat released to move solid ice from zero C to -50 C.
q5 = mass ice x specific heat ice x (Tfinal-Tinitial).

Total q = q1 + q2 + q3 + q4 + q5