Create an Endothermic Chemical Reaction

Most  endothermic reactions  contain toxic chemicals, but this reaction is safe and easy. Indeed, this experiment requires no toxic chemicals  -- a rarity in chemistry studies. Use it as a demonstration or vary the amounts of citric acid and sodium bicarbonate to make an experiment. Materials Citric acid and baking soda are available at most grocery stores. Citric acid is used for canning, while baking soda is used for baking. Heres what youll need: 25 milliliters of citric acid solution15 grams of baking sodaplastic foam cupthermometerstirring rod Creating the Reaction Pour the citric acid solution into a  coffee cup. Use a thermometer or other temperature probe to record the initial temperature.Stir in the baking soda  -- sodium bicarbonate. Track the change in temperature as a function of time.The reaction is: H3C6H5O7(aq) 3 NaHCO3(s) → 3 CO2(g) 3 H2O(l) Na3C6H5O7(aq)When you have completed your demonstration or experiment, wash the cup out in a sink. Tips for Success Feel free to vary the concentration of the citric acid solution or the quantity of sodium bicarbonate.An endothermic is a reaction that requires energy to proceed. The intake of energy may be observed as a decrease in temperature as the reaction proceeds. Once the reaction is complete, the temperature of the mixture will return to ​​room temperature.