Question 8.19 (Sixth Edition)

[Steve Magana 2I]

Question: (a) Calculate the heat that must be supplied to a 500.0-g copper kettle containing 400.0 g of water to raise its temperature from 22.0 degrees Celsius to the boiling point of water, 100.0 degrees Celsius. (b) What percentage of the heat is used to raise the temperature of the water?

I'm having trouble with this question, can someone help me please? Thank you!

[Tam To 1B]

So with this question, you want to find q of both the copper and the water and add it together to find the total amount of heat supplied.
You know that q = mCdeltaT
q(copper) = (500 g)(0.38 J/gC)(100-22 C) = 14.82 kJ
q(water) = (400 g)(4.184 J/gC)(100-22 C) = 130.54 kJ
q(total) = 14.82 + 130.54 = 145 kJ

For part (b), you take the heat of the water and divide it by the total since that much is used to raise the temperature of the water. 130.5/145 = 90%.

[Karyn Nguyen 1K]

Where did you get 0.38 J/gC?

[Ashley Kim]

0.38 J/g C is the specific heat capacity of copper.

[905775469]

Specific Heat of copper is 0.38J/C this is found in the table of specific heats of different compounds 4A.2 in the textbook.