Part 2: Enthalpy of reaction deltaH and Hess's law

Navigate to http://chemcollective.org/vlab/138

Step 1: click on "heats of reaction” in the top left corner to get a description of this lab and instructions for the procedure. Assume that all the solutions have a specific heat s=4.184 J/mol•°C. Perform 2 trials for each experiment using different masses or volumes. Enter the results in the table below, and show calculations for the last three columns beneath the table or on a separate page: 

Step 2: Questions:

1. Write a net ionic equation for reaction 3.

2. Calculate the difference between AHrxn2 and (AHrxnl + AHrxn3) and suggest what the result means.

3. How does this experiment illustrate Hess's law? (google Hess's law if necessary)

4. If the results deviate from the ideal, discuss any sources of error that may have resulted from the way the experiment was done.

5. Suggest how real-life data and results might differ from the simulation.

Symbols to cut and paste: