Calorimetry - Chemistry

Question

Calculate the final temperature of the system: A 50.0 gram sample of water initially at 100 °C and a 100 gram sample initially at 3.76 °C are mixed. The specific heat of water is 4.184 ^J/_g°C.

Answer 1

Heat lost by hot water MUST equal heat gained by cool water

heat lost by hot water = q = mC∆T

q = (50.0 g)(4.184 J/gº)(100º - Tf) where Tf is the final temperature

heat gained by cool water = q = mC∆T

q = (100 g)(4.184 J/gº)(Tf - 3.76º)

Setting these two equal to each other, we have...

(50.0 g)(4.184 J/gº)(100º - Tf) = (100 g)(4.184 J/gº)(Tf - 3.76º)

20,920 - 209Tf = 418Tf - 1573

627Tf = 22,493

Tf = 35.9º = final temperature