Specific heat capacity - heat energy transfer

AI Thread Summary
The discussion focuses on a homework problem involving the calculation of the mass of water that vaporizes when hot mercury is added to water. The key equations used are q=mcT for heat transfer and q=mL for phase change. The user attempts to equate the heat lost by the mercury with the heat gained by the water but questions the temperature change used in their calculations. They specifically seek clarification on the temperature difference of 100-10 in their equation. The user concludes that their calculated mass of vaporized water, 2.1 x 10^-5 kg, is incorrect and seeks assistance in identifying their error.
slaw155
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Homework Statement



Find the mass of water that vaporizes when 3.39 kg of mercury at 243 °C is added to 0.476 kg of water at 90.0 °

Homework Equations


q=mcT, q=mL


The Attempt at a Solution


When vaporising T=100degC. Heat lost by mercury = heat gained by water. 3.39kg x 139J/kg/C x (243-100) = 0.476kg x 4186J/kg/C x (100-10) + 22.6x10^5 J/kg x m
m= 2.1 x 10^-5kg is what I get which is the wrong answer. Where have I gone wrong?
 
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Where did the 100-10 come from?

Chet
 
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