The Preparation of Calcium Carbonate
Purpose: To create chalk (calcium carbonate) and to find the percentage yield in order to see the amounts of anhydrous sodium carbonate and calcium chloride were used up. Also to see if there’s any alterations like mass differentials.
1. To introduce the concept of “limiting factor” in a chemical reaction 2. To practice a. Writing a balanced equation b. Determining the number of moles of each reactant and product c. Deciding which chemical is the limiting factor d. Predict theoretical yield e. Determine actual yield f. Use error discussion
* 2 beakers * 2 watch glasses * Stirring rods * Filter paper * Funnel * Wash bottle * Anhydrous sodium carbonate * Calcium chloride
1. Mass approximately 4.0 grams of anhydrous sodium carbonate. Record exact mass. Transfer the mass to 50ml of distilled water. Stir until all the solid has dissolved. 2. Similarly, mass 4.0 grams of calcium chloride and transfer it to 50ml of distilled water. Stir until it dissolves. 3. Transfer, quantitatively, one solution to the other. 4. Mass a filter paper. 5. Filter the system ensuring all the precipitate is transferred from the beaker onto the filter paper. 6. Wash the precipitate in the filter paper with 5 mL quantity of distilled water. 7. Dry the precipitate in the drying oven overnight. 8. Mass the filter and precipitate.
Sources of error:
1. There may have been some of the precipitate which was still stuck onto the beaker, stirring rod and filter paper.
2. The electronic balance could have given us an incorrect amount of mass
3. The filtered may have not done its job properly and may have leaked out some of the precipitate in the water
4. Some of the substances in the surrounding surface may have affected the mass of the calcium carbonate such as dust particles.
5. Maybe the