Rock salt is a mixture of sand and sodium chloride. Sodium chloride is soluble in water but not in hexane. Sand is insoluble in both water and hexane. What is required to separate the sand from the sodium chloride? 1 filter paper 2 fractionating column 3 hexane 4 water

To separate the sand from the sodium chloride in rock salt, you will need the following:

1. Filter paper: This is used to physically separate the solid particles from the liquid. The mixture of sand and sodium chloride can be poured onto the filter paper, and the sand will be retained on the paper while the sodium chloride passes through as a solution.

2. Water: Since sodium chloride is soluble in water, you can use water to dissolve the sodium chloride and separate it from the sand. By pouring water onto the filter paper containing the sand and sodium chloride mixture, the sodium chloride will dissolve in the water and pass through the filter, leaving the sand behind.

3. Hexane: Hexane is not necessary for separating the sand from the sodium chloride. It is mentioned in the question that sodium chloride is not soluble in hexane, so using hexane would not be effective in separating the two components.

Therefore, the correct options for separating the sand from the sodium chloride in rock salt are:

1. Filter paper
2. Water