Duncan knows that it takes 36400 cal of energy to heat a pint of water from room temperature to boiling. However, Duncan has prepared ramen noodles so many times he does not need to measure the water carefully. If he happens to heat 0.600 pint of room-temperature water, how many kilojoules of heat energy will have been absorbed by the water at the moment it begins to boil?

Question

anonymous · Answer

Q=mc(Delta)T
Q=Heat
m= Mass (in grams)
c= Specific Heat Capacity
T= Temperature in degrees Celcius

Convert first:
.6 pint = 9.6 ounces = 272.15 grams
100 degrees Fahrenheit = 40.12 degrees Celcius
Heat capacity of water is 1.0038cal/g^C

Q= (.564)(1.0038)(40.12)
Q=10,960.15cal
Convert Cal to Joules
Q=45,857.26J
Convert Joules to Kilo Joules
Q= 45.86kJ

45.86kJ have been absorbed by the water when it begins to boil.