1. ENERGY CHANGES IN CHEMICAL REACTIONS
Deema Alotaibi Marah Naif
Sama Alnammari

2. Outline:
Objective.
Materials Required.
Procedure.
Summary.

3. Objectives:
Understanding the concept of thermo chemistry by measuring temperature changes in an insulated reaction vessel.
Measurement of the enthalpy of neutralization (the heat evolved in an acid-base reaction) of a strong acid with a strong base.
Determine the molar heat of solution of sodium hydroxide.

4. Materials Required: Styrofoam cup calorimeter. Thermometer.
Stirring rod.
Burette and burette stand.
Beaker.
Sodium hydroxide solid and aqueous
solution.
Hydrochloric acid, etc.

5. Procedure: 1) Weight the empty, clean the cup. 2) Add 100 ml of water
in the plastic empty cup.

6. 3) Weight the plastic cup, containing the water
3) Weight the plastic cup, containing the water. 4) Use the thermometer to determine the temperature of the water.

7. 5) Add 3 g of NaOH to the plastic cup that contains water
5) Add 3 g of NaOH to the plastic cup that contains water. 6) Weight the plastic cup, containing water & NaOH.

8. 7)Use the thermometer to determine the temperature of the liquid in the plastic cup. 8)Weight the plastic cup, containing the liquid.

9. Summary:
All chemical reactions involve energy changes. In some reactions, we are able to observe these energy changes as either an increase or a decrease in the overall energy of the system.
A chemical reaction involves the breaking of bonds in the reactants and the forming of bonds in the products.
It takes energy to break bonds.
Energy is released when bonds are formed.