posted by Sarah on .
How many kilojoules of heat are absorbed when 1.00L of water is heated from 18 degrees C to 85 degrees C?
Did I do this right?
1000g H2O x 4.18 x 67 = 280060 kilojoules
(my book says the specific heat for water in J/g x degrees C = 4.18, and for cal/g x degrees C = 1.00) Would i multiply 1000g x 67 x by 4.18 or 1?
Whether you use 1 cal/g*C or 4.18 J/g*C depends upon what unit you want the answer in. The first one gives the answer in calories, the second in joules. Your math is ok but the answer is not kJ, but J. You need to divide you answer by 1000 to convert to kJ.