Purpose: The purpose of this experiment is to experimentally determine the molar mass of carbon dioxide.
Procedure & Observations.
First, we placed approximately 20 g of calcium carbonate in a wide-mouth bottle and covered it with water. I then put together the generator consisting of a 2-hole stopper, a glass bend, and a thistle tube. I then picked up a drying tube of anhydrous calcium chloride that was supplied for us. I clamped the tube in place on the ring stand, and then connected the one end of the glass bend of the generator. I obtained a 250 ml Erlenmeyer flask from the locker and inserted a glass tube extending one inch from the stopper. My lab partner and I determined the mass of the flask with the stopper assembly in place. Next, we attached the flask to the drying tube with an 8 in. piece of rubber tubing and loosely placed the neck of the flask in place. Once the apparatus was assembled we ready to generate CO2. Mr. Henze then poured highly concentrated HCl slowly into the thistle tube. We observed when the HCl was poured into the generator with the marble chips the reaction began immediately causing bubbles to surface. After patiently observing the reaction for 15 minutes while the CO2 filled the flask we recorded the room temperature, and momentarily tightened the stopper on the flask a couple of times to observe that the liquid in the generator is backing up the funnel tube which means CO2 is still being delivered. Once the CO2 was created we detached the rubber tube form the flask we tighten the stopper and determined the mass of the stoppered flask and CO2 gas. After determining the mass we immediately determined the temperature of the CO2 by inserting a thermometer in the flask. During this time I recorded the barometer reading in mm. Last of all we filled the flask with water to the bottom of the stopper, and measured the volume of the water by transferring it into a graduated cylinder.