Hot Or Not?  Depends On The Chemistry!

Epstein 8th graders in Andrew Lardie’s science class at The Epstein School used an integrated approach to observing and comparing chemical reactions that are exothermic (heat-releasing) and endothermic (heat-absorbing). 

They used Activboards to graph and visualize results, laptop computers to document data and research information, thermometers and stop watches to measure temperature changes over time, as well as various chemicals to mix.

The two types of chemical reactions the students experimented with were:

Endothermic in which the temperature drops- Mixing Sodium Bicarbonate NaHCO3 (baking soda) and Acetic acid solution CH3COOH (vinegar): This reaction causes effervescence (bubbling) because it produces CO2 gas (carbon dioxide), CH3COONa (a type of salt), and H2O (water).

Exothermic in which the temperature increases- Mixing yeast and hydrogen peroxide (H2O2): Hydrogen peroxide is not a very stable compound, so it is always decomposing to water (H2O) and oxygen gas (O2). Under normal conditions, the decomposition goes very slowly.  However, in this reaction the yeast catalyzes the decomposition, making the reaction go much more quickly and in the process releases heat.

The Epstein School is renowned for its use of cutting-edge technology and hands-on science education.  Integrating these disciplines is one of the ways The Epstein School remains a leader in education and became a 2005 US Department of Education Innovator.

To learn more about The Epstein School please visit www.epsteinatlanta.org.