Why was gravity filtration used instead of evaporation to isolate the calcium cabornate?
because it dissolves in water and could not be separated
Gravity filtration was used instead of evaporation to isolate the calcium carbonate because filtration is a separation technique used to separate solid particles from a liquid mixture. In this case, calcium carbonate was obtained as a solid precipitate from a reaction.
Gravity filtration is a preferred method for isolation as it involves passing the mixture through a filter paper placed in a funnel, allowing the liquid (filtrate) to pass through while retaining the solid particles (precipitate) on the filter paper. The liquid can then be collected separately, leaving behind the solid calcium carbonate.
Evaporation, on the other hand, involves heating the mixture to evaporate the liquid component, leaving the solid behind. However, this process may not be suitable in certain cases. In the case of isolating calcium carbonate, using evaporation might result in the formation of impurities and loss of the desired compound due to its potential decomposition or dissociation at high temperatures. Gravity filtration provides a more gentle and controlled separation process and helps in obtaining a pure solid sample.
Gravity filtration was used instead of evaporation to isolate calcium carbonate because calcium carbonate is insoluble in water, which means it does not dissolve in water. Evaporation is the process of removing the liquid component from a solution to leave behind the dissolved solid. If calcium carbonate were dissolved in water, as some substances are, evaporation would be an effective method for isolation. However, since calcium carbonate is not soluble in water, gravity filtration is a more suitable technique.
To understand why gravity filtration was chosen, we need to know the properties of calcium carbonate. Calcium carbonate has low solubility in water, making it practically insoluble. This means that when calcium carbonate is mixed with water, it remains as solid particles and does not dissolve. In contrast, substances that are soluble in water will dissolve and form a homogeneous solution.
Gravity filtration is commonly used to separate solids from liquids when the solid is insoluble. The process involves passing the mixture through a filter paper or other porous material, which allows the liquid (called the filtrate) to pass through, while the solid particles are retained on the filter (called the residue). In this case, the calcium carbonate particles would be captured on the filter paper, and the water (which does not contain any dissolved calcium carbonate) would pass through as the filtrate.
To execute gravity filtration, follow these steps:
1. Prepare a filter setup: Place a funnel on top of a filter flask or beaker. Ensure that the filter paper is properly fitted inside the funnel to create a barrier for the solid particles.
2. Wet the filter paper: Wet the filter paper with a small amount of the solvent (in this case, water). This helps to create a tight seal against the funnel walls and prevents the liquid mixture from seeping through the sides.
3. Set up the gravity filtration apparatus: Pour the mixture containing the calcium carbonate into the filter funnel. It is important to pour slowly to avoid overflowing the funnel. The liquid component (filtrate) will pass through the filter paper and collect in the filter flask or beaker below, while the solid calcium carbonate particles will be retained on the filter paper.
4. Collect and dry the residue: Once all the liquid has passed through, carefully remove the filter paper with the captured calcium carbonate residue. The residue can then be dried, either by leaving it in a warm area or using a drying oven, depending on the specific requirements.
By utilizing gravity filtration, the insoluble calcium carbonate can be effectively separated from the liquid component without the need for evaporation.