A thermos bottle contains 250 g of coffee at 88 0C. You then decide to add 27 g of milk at 5 0C. What is the equilibrium temperature of the mixture? Assume no heat is loss to the thermos bottle and that the specific heat of water, coffee and milk is about the same.

Question

A thermos bottle contains 250 g of coffee at 88 0C.  You then decide to add 27 g of milk at 5 0C.  What is the equilibrium temperature of the mixture? Assume no heat is loss to the thermos bottle and that the specific heat of water, coffee and milk is about the same.

Answer is 79.909 degrees C, but don't know how to get that

Chanz · Answer

mc(Tf - Ti)coffee + mc(Tf - Ti)milk = 0 solve for Tf (and you'll need to look up the specific heat of water)