Modeling Energy Changes Student Guide on Edge Step 2: Write and Balance the Chemical Equation.
a) Read the word equation: "Propane gas plus oxygen gas produces _."
b) Convert the word equation to a chemical equation and complete the reaction. Be sure to balance the chemical equation.
c) Record the balanced chemical equation on the Student Worksheet.
Step 3: Determine the amount of energy change in the reaction.
a) Use the table of enthalpy values (Table A) provided in the Student Worksheet to locate the enthalpy of formation (DeltaHt) for each reactant and each product. Record these values along with the reactants and products in Table B of the Student Worksheet.
b) Determine the total enthalpy of the reactants and the total enthalpy of the products Record these values in Table C of the Student Worksheet.
c) Use the following formula to find the net change in enthalpy for the reaction and to determine whether the reaction is endothermic is endothermic or exothermic.
DeltaHrxn= E (Delta Hf, products)- E (DeltaHf, ractants)
Record your answers in Table D.
Step 4: Model the energy change in the reaction.
a) Create an energy graph that illustrates the energy change in the reaction.
b)Construct your graph on a blank sheet of paper. Be sure to label the axes, provide a title, and identify the reactants and product on the graph.