Describe how a sample of pure sodium chloride can be obtained from a mixture of iodine, sodium chloride and sand.
To obtain a sample of pure sodium chloride from a mixture of iodine, sodium chloride, and sand, one could use the process of filtration and evaporation.
First, the mixture would be dissolved in water. Iodine is not soluble in water, so it would remain as a solid in the mixture. The sodium chloride and sand, however, would dissolve in the water.
Next, the mixture would be passed through a filter. The sand, being insoluble, would be caught by the filter and can be discarded. The sodium chloride solution would pass through the filter, along with any remaining iodine.
The next step would be to evaporate the water from the sodium chloride solution. This can be done by heating the solution in a container until all the water has evaporated, leaving behind solid sodium chloride.
After the evaporation process is complete, the solid sodium chloride can be scraped from the container and collected as a pure sample. This sample can then be stored and used for various purposes.