jedes guaranteed Today, let us observe the reaction between concentrated hydrochloric acid and concentrated sodium hydroxide and between ammonium chloride and barium hydroxide and identify the reaction. The reaction between concentrated hydrochloric acid and concentrated sodium hydroxide is a neutralization reaction resulting in the formation of salt and water. To conduct this experiment, we need the following materials. Dropper concentrated hydrochloric acid, concentrated sodium hydroxide, ammonium chloride, barium hydroxide, beakers, glass rod, thermometer, spatula and moist pH paper. Let us note the room temperature. Room temperature is 25 degrees Celsius. Take a clean and dry beaker and add 10 ml of concentrated hydrochloric acid. To it add 10 ml of concentrated sodium hydroxide. Care should be taken while adding sodium hydroxide in drops. Stir the mixture well with the help of thermometer. Neutralization occurs resulting in the formation of salt and water. Note the temperature again. Temperature is 45 degrees Celsius. Temperature increases as neutralization occurs. This is due to the fact that heat is liberated. We can also touch the beaker and feel the heat produced. Care should be taken while touching the beaker after the reaction. Since heat is evolved, hence it is an exothermic reaction. Note the room temperature again after cleaning the thermometer. Room temperature is 25 degrees Celsius. Take a clean and dry beaker and add the two mixtures, that is ammonium chloride and barium hydroxide. Let us stir the mixture well with the thermometer. The mixture becomes slushy and a liquid is formed along with a white suspension. The temperature decreases as we can see the mixture freezes. Now the temperature is 12 degrees Celsius. Since the heat is absorbed, hence it is an endothermic reaction. We can detect the ammonia liberated either by smelling it or by detecting with the help of moist litmus paper. From this experiment, we can infer that the reaction between concentrated hydrochloric acid and concentrated sodium hydroxide is an exothermic reaction as heat is evolved while the reaction between ammonium chloride and barium hydroxide is an endothermic reaction as heat is absorbed. .