Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Help with understanding how to figure out the amount of heat to boil away water.

  1. Jun 15, 2011 #1
    1. The problem statement, all variables and given/know

    2300 grams of water is heated. If this water starts at a temperature of 17 degrees Celsius, what amount of heat is needed to boil away all of this water? Note that the specific heat of water is 1 calorie per gram per degree Celsius, the Heat of vaporization of water is 540 calories per gram, and water boils at 100 degrees Celsius.

    3. The attempt at a solution

    I figured that this would be the best formule for me to use Q = c m ΔT, and Qv = m Lv .

    Since water boils at 100 degrees celsius, I assumed that I should subtract 100-17 to get 83 degrees as the differnce in temperature.

    Can I please get assistance with understanding this probelm.
     
  2. jcsd
  3. Jun 15, 2011 #2
    Actually, you are on the right track. Use your two formulas. The total heat is the sum of the two.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook