Question

A stainless steel spoon weighs 27.4 g and is at a temperature of 18.5°C. It is immersed in 86.5 mL of cough feet the coffee’s temperature is 84°C in a thermal flask. What is the final temperature of the spoon plus the coffee

Answer 1

heat gained by spoon = heat lost by coffee

C Fe = 0.46kJ/Kg - K = 0.46J/g-C

C H2O = 4.184J/g-C

deltaT spoon = Tfinal - 27.6C

deltaT coffee = 84C - Tfinal

27.6gFe x 0.46J/g-c x (T - 18.5C) = 84.2g water x 4.184J/g-c x (84C - T)

12.7T - 234.88 = -352.29T + 29592.95

364.99T = 29827.83

T = 81.72C