To separate common salt (NaCl) and marble powder (CaCO₃), you can effectively use a method based on their different properties, specifically their solubility in water. Common salt dissolves readily in water, while marble powder does not.
Simple Separation Method: Dissolution and Filtration
The most straightforward method for separating a mixture of common salt and marble powder involves dissolving the salt in water and then filtering out the insoluble marble powder. This process leverages the principle that substances behave differently when mixed with a solvent.
According to the reference provided:
- To separate the components of a mixture of common salt (NaCl) and marble powder (CaCO₃), add water to the mixture.
- Stir the mixture to dissolve the common salt in water.
- Marble powder will not dissolve in water.
- Filter the mixture using filter paper.
Step-by-Step Process
Here's a breakdown of the steps you would follow:
- Add Water: Combine the mixture of common salt and marble powder with water in a container, such as a beaker or a glass.
- Stir: Vigorously stir the mixture. As you stir, the common salt will dissolve in the water, forming a salt solution. The marble powder, being insoluble, will remain as a solid suspended in the water.
- Prepare for Filtration: Set up a filtration apparatus. This typically involves a filter funnel lined with filter paper, placed over another container (like a flask or beaker) to collect the liquid.
- Filter: Carefully pour the mixture through the filter paper. The liquid (water containing dissolved salt) will pass through the tiny pores in the filter paper and collect in the container below. The solid marble powder, which cannot pass through the pores, will be trapped on the filter paper.
After filtration, you will have successfully separated the two components: the marble powder will be left as a residue on the filter paper, and the common salt will be present as a solution in the collected liquid (filtrate).
Why This Method Works
The success of this separation technique relies entirely on the differing solubilities of salt and marble powder in water.
| Substance | Chemical Formula | Solubility in Water | Behavior in Water Mixture | Separated Phase |
|---|---|---|---|---|
| Common Salt | NaCl | High | Dissolves, forms solution | Liquid (Filtrate) |
| Marble Powder | CaCO₃ | Very Low (Insoluble) | Remains solid, suspended | Solid (Residue) |
Because marble powder is insoluble, it can be easily separated from the salt solution using a simple physical barrier like filter paper.
