Another HELP problem: Steam to Ice

[delecticious]

Another URGENT HELP problem: Steam to Ice

Homework Statement

How many J of energy must be removed when 127.0 g of steam, at a temperature of 153.0°C, is cooled and frozen into 127.0 g of ice at 0°C? Take the specific heat of steam to be 2.1 kJ/(kg·K).

Homework Equations

Q1 = mc(delta T) <---- c= heat capacity of steam
Q2 = mLv
Q3 = mc(deltaT)<---- c=heat capacity of water
Q4 = mLf

The Attempt at a Solution

first I converted grams to kilograms and got .127kg for the mass then I follwed through with my equations
Q1 = (.127)(2100)(153-100)= 1.4135E4
Q2 = (.127)(2259.36)= 2.869E2
Q3 = (.127)(4186)(100-0)= 5.316E4
Q4 = 4.241E4

I added these up and got a total Q of 1.10E5, what am I doing wrong?

 

[mgb_phys]

https://www.physicsforums.com/showthread.php?t=198655

 

[delecticious]

he had a different problem (that is to say a different problem regarding the same problem) than me, I just need to know if I'm doing it right and when went wrong.

 

[mgb_phys]

You have the constants wrong.
specifically the heat of vapourisation - the water/steam change should be the largest energy.
Just put you hand over a kettle to find out!

 

[Astronuc]

Q2 = (.127)(2259.36)= 2.869E2

Please check units!

I strongly recommend writing units with values, so that one properly accounts for orders of magnitude.

 

[delecticious]

I seriously don't know how I keep messing up my units, but thanks again.