Endothermic Vs

Endothermic vs. Exothermic Experiment: When there is a chemical reaction that takes place between substances, there can be many outcomes of the mixture. In this experiment, an experiment will be conducted to test one of these outcomes. Endothermic and exothermic reactions occur when energy is transferred during a chemical reaction. Endothermic is when reactions cause energy to be absorbed into the new substance, and exothermic is when energy is released. Temperature is also an indicator of which kind of reaction has occurred in a chemical experiment The following experiment requires you to measure the temperature of a mixture of baking soda and vinegar. The experimental question asked should be: Will an endothermic or exothermic reaction occur when baking powder and vinegar together? My hypothesis is that an exothermic reaction will occur when you baking soda and vinegar.

Materials: 

1 Teaspoon Baking Soda

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250 mL of Vinegar

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Plastic Cup

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Graduated Cylinder

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Thermometer

Additional Recommended Safety Notes: -

An adult and goggles nearby during experiment

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Any long hair tied back

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Clean surfaces to work on

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Any cleaning supplies nearby to pick up mess.

Experiment Steps: 1. Measure 250 mL of Vinegar into a Graduated Cylinder. 2. Pour measured Vinegar into Plastic Cup (it is recommended you have the plastic cup in safe place in case of spill). 3. Measure and take note of the Temperature of the Vinegar before continuing. 4. Measure 1 level Teaspoon of Baking Soda.

5. Once water is set up, take the measured Vinegar and drop it into the Plastic Cup. 6. Observe and take notes about the reaction occurring. 7. Now, take the thermometer and check the temperature of the mixture again. Record any changes. 8. Clean up materials once experiment has concluded. 9. Repeat experiment if necessary.

Observations During Experiment: Before adding the baking soda, the vinegar was at room temperature, about 74 degrees. After adding the vinegar, there was lots of fizzing from the chemical reaction. Once fizzing had died down, recorded temperature was about 72.5 degrees. After about 2 minutes the temperature continuously went back up to 74 degrees.

Analysis and Conclusion: My hypothesis that the reaction would be exothermic was proven correct. The chemical reaction between the baking soda and vinegar caused the mixture to decrease by about a degree and a half (as in my own experiment it started at 74 degrees and decreased to 72.5 degrees). This means it is exothermic. The reaction caused energy to be taken away, thus the temperature decreased as well. I also previously did tests to see how much of a reaction I could get from the experiment. The first test was the same procedure, just a different amount of baking soda and vinegar, where the temperature would barely get down to 73 degrees. Without wasting too much material, the written amount above formulated the best reaction.