The most suitable separation technique for a mixture of sodium chloride and water is evaporation. This method utilizes the principle of selective vaporization, where the liquid water evaporates, leaving behind the dissolved sodium chloride. Here's how evaporation can be used for the separation:

Evaporation:

1. Heating: Place the mixture of sodium chloride and water in a container and apply heat to the solution.

2. Vaporization: As the temperature increases, the water molecules gain enough kinetic energy to overcome the intermolecular forces holding them together and escape into the vapor phase. Sodium chloride, being a non-volatile compound, remains in the solution.

3. Collection: Capture the water vapor by condensing it back into liquid form. This can be achieved by using a condenser or collecting the vapor in a cool container.

4. Recovery of Sodium Chloride: Once the water has evaporated, the remaining substance will be the concentrated sodium chloride solution. You can further evaporate this solution to obtain solid sodium chloride crystals.

Evaporation is commonly used in various industries for the separation and purification of substances, including the production of salt from seawater. It is also employed in laboratory settings for recovering dissolved solids from solutions.