Question

With a growing human population, scientists believe that clean freshwater will become scarce (limited). A possible solution is to desalinate salt water.
Using what you've learned in this unit, describe the type of a mixture salt water is and explain how you would separate and collect fresh water from the salt water in the ocean

Answer 1

Mixtures are of 2 types.

1) Homogeneous mixture : In this type of mixture, the components of the mixture are present in the same phase. For example, Air. Air is a mixture of different gases which cannot be distinguished from each other.

2) Heterogeneous mixture : In this type pf mixture, 2 or more phases can be seen. The composition of the different components is not the same throughout  the mixture.

Ex. mixture of oil and water. Here we can see 2 different phases one consisting of oil layer and the other made of water layer.

Salt water is a mixture of salt and water. Since salt is completely soluble in water, it creates a homogeneous mixture when mixed with water. We cannot distinguish salt and water once they are mixed.

To get fresh water from the salt water in the ocean, we can set up a simple distillation unit . In this, the salt water is heated to its boiling point and the vapors thus formed are allowed to cool which condense and create liquid water. This can be used as fresh water.