An ice cube having a mass of 50 g and an initial temperature of -20⁰C is place in 400 g of water 30⁰C water. What is the final temperature of the mixture if the effects of the container can be neglected?

1 answer

the sum of the heats gained equals zero.

50(0-(-20)) +50*Lf +50(tf-0)+400(Tf-30)=0
you know the heat of fusion for ice (Lf), solve for Tf.