Unit 3 Science Portfolio Kj

Endothermic and exothermic Reactions Experiment Question: How does the absorption and release of energy affect temperature change during a chemical reaction?

Hypothesis: If Epsom salt has an impact with water then energy will be absorbed in the water making it colder because it will form a new substance called salt water, and salt water has a lower freezing point than regular water.

Materials: 1. Epsom salt 2. A glass container 3. Water pitcher 4. Thermometer

5. Measuring Spoons 6. Safety goggles 7. Safety gloves 8. Cardboard

Safety Procedure: 1. Using the cardboard, unfold it and apply it to whatever surface that is being worked on for protection. 2. Apply safety goggles 3. Apply safety gloves 4. Wear closed toed shoes 5. Tie hair back 6. Adult supervision required

Experimental Procedure: 1. Safety procedure 2. Use a water pitcher to pour room temperature water into a glass cup to around the middle mark.

3. Record temperature using a thermometer before the reaction. 4. Pour a tablespoon of Epsom salt in the water and wait till it dissolves using measuring spoons. 5. Record the temperature after the reaction to compare energy levels. 6. Record data needed to solve the experiment.

Data Table Reaction

Observations Before Reaction

Observations During Reaction

Observations After Reaction

Epsom salt + water

Water looks clear and is a liquid substance.

The salt sank right to the bottom as soon as it was poured in.

The temperature sank to about 70 degrees Fahrenheit.

Starts to dissolve a little while after poured in.

The liquid turned whiter.

Epsom salt is white, grainy, and rocky.

The water temperature starts The water gained at 75 degrees particles and Fahrenheit. looks less clear.

Particles have increased since starting the reaction.

The water felt

There are some

Starts to look

room temperature.

more cloudy looking closely.

bubbles fizzing up to the top of the container.

Analysis/Conclusion In conclusion to this shocking experiment, the hypothesis was proven correct, it claimed the Epsom salt would give energy to the water that would make it colder than it was before, and create a new substance known as salt water. The data shows that before the reaction the water temperature was at 75 degrees Fahrenheit, and after the experiment, it was at 70 degrees Fahrenheit. This test proved it to be an endothermic reaction since the water obtained more energy than released and resulted in colder temperature as a conclusion. The absorption of energy in the experiment proves how it affected the temperature change. This is how the absorption and release of energy affect temperature change during a chemical reaction.