This experiment is to show how much carbon dioxide is produced during the reaction between an acid (hydrochloric acid) and marble.Equipment:Hydrochloric Acid (20ml) - 0.5M, 1M, 2MMarble Chips (2g per test)Large Measuring CylinderPlastic Bowl (3/4 full of water)Rubber TubingGlass Conical FlaskStopwatchMethodThe first thing that we did was fill the plastic bowl with water. We only filled it up 3/4 of the way because otherwise the water displaced into the bowl during the experiment would cause it to overflow onto the floor and work surfaces. This would create a safety hazard, maybe causing slipping. Then we weighed out the marble chips.
We used 2g of marble chips per test in order to create a more noticeable reaction than if we were to use a lesser amount. The next step we took was to fill the large cylinder with water and then flip it upside down into the bowl (with our hand over the top of the cylinder).This meant that the water was still in the cylinder After this we measured out 20ml of one of the acid concentrations (0.5,1 or 2M). Again we used 20ml to create a more noticeable reaction (than if we used a lesser amount).
We then put the measured acid into the conical flask. After this we placed a rubber tube underneath the cylinder in the water.This was to be connected to the conical flask where the reaction was to take place. Therefore the cylinder would catch any carbon dioxide produced from the reaction. Then we put the 2g of marble chips into the conical flask with the acid. We then attached the rubber tubing to the top of the flask, which would carry the carbon dioxide into the measuring cylinder.
We then recorded in a table how much water was displaced from the cylinder by the carbon dioxide every ten seconds. This showed us how much carbon dioxide was being produced from the reaction between the marble and hydrochloric acid and also the rate of which it is being produced. Subsequently we repeated the experiment (from steps 2-7) using a different concentration of acid each time but keeping the amount of acid and the amount of marble the same. We did this to ensure that it was a fair test.
