How much energy is needed to convert 20 grams of ice at -10 degree C into steam at 110 degree C?

Express your answer in KJ





To do this you will need the following data:


Specific heat capacity of H2O (L) = 4.2 J/g degree C


Specific heat capacity of H2O (S) =2.1 J/g degree C


Specific heat capacity of H2O (G) = 4.2 J/g degree C


Latent heat of vaporization of water = 2.3 KJ/g


Latent heat of fusion (melting) of water = 336J/G





I found this question in my grade 12 Chemistry book, i tried to do it, but can't figure it out





Thanks

How much energy is needed to convert 20 grams of ice at -10 degree C into steam at 110 degree C?
Temp. change = Mass(g) x SH (J/g/°C) x °C ΔT.


Phase change = Mass x LH.


You have the SH of steam as 4.2J/g/°C...it's 2.01J/g/°C.


*..Ice at -10°C to 0°C = 20 x 2.1 x 10 = 0.420kJ.


*..Ice at 0°C to water at 0°C = 20 x 336 = 6.7kJ.


*..Water at 0°C to 100°C = 20 x 4.2 x 100°C = 8.4kJ


*..Water at 100°C to steam at 100°C = 20 x 2.3 = 46kJ


*..Steam at 100°C to 110°C = 20 x 2.01 x 10 = 0.402kJ





Total heat required (kJ) = 0.42 + 6.7 + 8.40 + 46. + 0.402


= 61.92kJ.