Science Homework Help

I am doing a lab and need to calculate the change in temperature of Mixture (Hess’s Law). I have recorded the

temperature for the mixture of two solutions in 20 second intervals for 5 minutes. I have my initial temperature of the first solution, initial temperature of the second solution, the average initial temperature of the two separate solutions, the highest temperature of mixture (over the 20 second intervals in 5 minutes).

How do I calculate the change in temperature of the mixture?

Thank You!