Essay On Exothermic Reaction

Chemical reactions which cause a change in temperature can be categorized as endothermic or exothermic reactions. In an endothermic reaction, energy will be absorbed by the chemical mixture; in an exothermic reaction, energy will be released. If a beaker is submerged in a mixture with a cooler temperature than the water inside the beaker, heat will be transferred from the water in the beaker to the chemical mixture, making the chemical mixture undergo an endothermic reaction. When the chemical mixture is warmer than the water inside the beaker, heat will be released from the water inside the beaker to the chemical mixture, making the chemical mixture undergo an exothermic reaction. The goal of this lab was to learn about endothermic reactions, exothermic reactions and

One thermometer was then placed into the 20mL of water in each graduated cylinder and left to sit at room temperature. When both thermometers reached the same temperature (the assumed ‘room temperature’), the water from one graduated cylinder was transferred into a 100mL beaker. The water from the other graduated cylinder was poured into a polystyrene cup. Using a scale and a weighboat, precisely 2 grams of ammonium chloride (NH4Cl) was measured and placed into the polystyrene cup with the 20mL of water. The chemical compound and the water were mixed together using a glass rod until the chemical was thoroughly dissolved. After the chemical had dissolved, the beaker containing 20mL of room temperature water was placed into the chemical mixture with a thermometer in the beaker as well. The lid for the polystyrene cup was then placed onto the cup, and the stopwatch began timing. The lid was not removed until exactly 2 minutes had passed, and the thermometer was taken out. The final temperature was recorded and the difference in temperature change was calculated by subtracting the initial water temperature from the final water temperature. This process was