How much heat in kj is evolved in converting 1.00 mol of steam at 145.0 C to ice at 55.0 C? The heat capacity of steam is 2.01 j.gC and of ice is 2.09 j/gc

with sig figs its comes to a total of 58.0 KJ
you will also need the heat of crystallization and condensation along with the specific heat of liquid water: 333 J/g, 2260 J/g, and 4.184 J/gC respectively
also while i was at it i checked you constants as well and they are marginally different from mine: (steam) 2.06 J/gC, and (ice) 2.11 J/gC ......... but they are close enough to not make a difference here
heres the math:
(45 + 100 + 55 = 200 which is the total change in temperature, the negative in the math work shows the direction the temperature is going)
(45 * 2.06) + (2260) + (100 * 4.184) + (333) + (55 * 2.11) = 3220.15 J/g
H_2_O has 18 g/mol > 1 mol * 18 g/mol = 18 g of water
18 * 3220.15 = 57962.7 J > /1000 = 57.9627 KJ > 58.0 KJ
you will also need the heat of crystallization and condensation along with the specific heat of liquid water: 333 J/g, 2260 J/g, and 4.184 J/gC respectively
also while i was at it i checked you constants as well and they are marginally different from mine: (steam) 2.06 J/gC, and (ice) 2.11 J/gC ......... but they are close enough to not make a difference here
heres the math:
(45 + 100 + 55 = 200 which is the total change in temperature, the negative in the math work shows the direction the temperature is going)
(45 * 2.06) + (2260) + (100 * 4.184) + (333) + (55 * 2.11) = 3220.15 J/g
H_2_O has 18 g/mol > 1 mol * 18 g/mol = 18 g of water
18 * 3220.15 = 57962.7 J > /1000 = 57.9627 KJ > 58.0 KJ

I have a detailed look at a problem like yours here:
http://www.chemteam.info/Thermochem/Time…
My problem goes from 10 to 120 while yours goes from 145 down to 55. So, just reverse yours and go from 55 to 145 and follow the pattern in my example.
If you back up to the thermochemistry menu:
http://www.chemteam.info/Thermochem/Ther…
and look under problem sets, you'll see some links that take you to a variety of solved examples.
http://www.chemteam.info/Thermochem/Time…
My problem goes from 10 to 120 while yours goes from 145 down to 55. So, just reverse yours and go from 55 to 145 and follow the pattern in my example.
If you back up to the thermochemistry menu:
http://www.chemteam.info/Thermochem/Ther…
and look under problem sets, you'll see some links that take you to a variety of solved examples.