Chemistry basics lab: 02/18/2021

 This week we took a deeper look into exothermic and endothermic reactions. First as a group we discussed and defined each reaction. A exothermic reaction is when energy is released in the form of heat, and a endothermic reaction is when heat is absorbed from the surroundings. 

Materials:

Calcium chloride

Sodium bicarbonate (baking soda)

Citric acid

Beakers

Stirring rods

100ml graduated cylinder

Thermometer

Exothermic reaction: My partner and I first used the thermometer verify that the water was at room temperature. Next we measured out 10 ml of calcium chloride chips and added it to the water, creating a solution. Following this we recorded the change in temperature every 5 seconds for 1 minute. Our data showed that the temperature was rising at a constant rate, and the maximum temperature was 30 degrees Celsius. As seen below we created a graph based off our data to represent the changes in temperature over time. 

Exothermic reaction: Similar to the last experiment, my partner and I first checked that the water was at room temperature. Secondly, we added 10ml of citric acid to the water and stirred until it was completely dissolved. Next we added 10ml of baking soda to the solution, within seconds the solution began to spill over. Following this we began to monitor the temperature every 5 seconds for 1 minute. Our data showed that the temperature was decreasing quickly, our lowest recorded temperature was 2 degrees Celsius. Our data is represented in the graph below.   

Photos from the lab: