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    I've tried answering it myself and I think I have the right answer, could some1 pls give it a go?

    Calculate the amount of heat required to completely convert 50g of ice at 0 degrees Celsius to steam at 100 degress Celsius. The specific heat capacity of water is 4.18kJ/kg/C, the specific hlatent heat of fusion of ice is 334kJ/kg and the specific heat of vaporisation of water is 2260kJ/kg.

    Thx!
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    What you'd do is convert to correct units: 50g is 0.05kg and all kJ to J by multiplying by 1000, then since it's ice you'd work out the energy to convert to water: 0.05 × 334000J gives 16700J to get to water.
    Then you'd work out the energy required to heat to 100 degrees Celsius: 0.05 x 4180J = 209J
    You'd finally calculate the energy for vaporization as it completely converts to steam as 0.05 x 2260000J = 113000J
    Finally total these to get 129909J required or 129.909kJ depending on the questions unit preferences

    EDIT:
    Forgot to factor in the change in temperature:
    0.05 x 4180 × 100 = 20900J
    New total would be 150600J or 150.6kJ
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    (Original post by AmmarTa)
    What you'd do is convert to correct units: 50g is 0.05kg and all kJ to J by multiplying by 1000, then since it's ice you'd work out the energy to convert to water: 0.05 × 334000J gives 16700J to get to water.
    Then you'd work out the energy required to heat to 100 degrees Celsius: 0.05 x 4180J = 209J
    You'd finally calculate the energy for vaporization as it completely converts to steam as 0.05 x 2260000J = 113000J
    Finally total these to get 129909J required or 129.909kJ depending on the questions unit preferences
    YESSS! Now I can tick it - thx my teacher's a little too fast paced!
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    (Original post by streetdude28)
    YESSS! Now I can tick it - thx my teacher's a little too fast paced!
    You're welcome
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    (Original post by AmmarTa)
    Thanks, you wouldn't mind +rep right?
    np
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    (Original post by AmmarTa)
    Thanks, you wouldn't mind +rep right?
    youre not meant to ask shhh
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    (Original post by amaraub)
    youre not meant to ask shhh
    Didn't know, woops:O
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    (Original post by AmmarTa)
    What you'd do is convert to correct units: 50g is 0.05kg and all kJ to J by multiplying by 1000, then since it's ice you'd work out the energy to convert to water: 0.05 × 334000J gives 16700J to get to water.
    Then you'd work out the energy required to heat to 100 degrees Celsius: 0.05 x 4180J = 209J
    You'd finally calculate the energy for vaporization as it completely converts to steam as 0.05 x 2260000J = 113000J
    Finally total these to get 129909J required or 129.909kJ depending on the questions unit preferences
    Isn't this incorrect? E= mc delta T for heating water, you haven't multiplied by 100 for the temperature change.
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    (Original post by haarithiop)
    Isn't this incorrect? E= mc delta T for heating water, you haven't multiplied by 100 for the temperature change.
    Oh crap you're right, my bad! energy is shc×massxchange in temp
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    (Original post by AmmarTa)
    Oh crap you're right, my bad! energy is shc×massxchange in temp
    150.6kJ
 
 
 
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