For the energy absorbed by a system to be quantifiable , it needs a thermodynamic parameter called enthalpy , better known in formulas by the letter “H” . If energy is released around a system, the enthalpy change would have a negative value. On the contrary, if the variation is positive, it reflects the absorption of heat from the surroundings.
Examples of Exothermic Reaction
- The hot ice or sodium acetate, is created through a crystallization process mineral frozen solutions instead of cold release, releases heat.
- The volcanic eruptions simulated , commonly in schools or projects originate from the combination of soda and vinegar, giving as result an exothermic reaction which releases large amounts of foam.
- The combination of the steel shavings plus the vinegar , generate an oxidation reaction through a slow combustion process.
- When you light a candle , you also generate an exothermic reaction, since the combustion coming from the paraffin and the wick of the candle, release quantities of heat and light.
- The combination of butane gas with oxygen generates an exothermic reaction.
- If you mix nitrous oxide plus nitric oxide and carbon bisulfate in a laboratory tube, you will most likely have an exothermic reaction that results in a sound similar to that of a dog barking .
- Breathing can also generate an exothermic reaction. The cells of your lungs, by combining glucose with oxygen, are transformed, releasing carbon dioxide and heat.
- When you put water in the fridge to freeze it , that water releases heat so it can harden. This process of releasing energy is an exothermic reaction.
- Mixing potassium chlorate with edible gummy bears and exposing it to high temperatures can cause an explosion.
- By combining hydrogen peroxide with potassium permanganate , you cause the hydrogen peroxide to break down and release large amounts of smoke and heat.