Chemistry 2023 JAMB Past Questions - Question 1: Sodium chloride can be obtained from brine through

Correct Answer

C

Explanation

The solution to obtaining sodium chloride from brine typically involves a process called "evaporation and crystallization." Here's a basic outline of the process:

1. Brine Collection: Brine, which is a solution of salt (sodium chloride) in water, is collected. It can be sourced from various places such as saltwater lakes, salt mines, or by dissolving rock salt in water.
2. Purification: Depending on the source, brine might contain impurities like magnesium and calcium ions. These impurities are typically removed through various purification methods such as precipitation or filtration.
3. Concentration: The purified brine is then concentrated to increase the salt content. This is often done through evaporation, either by exposing the brine to heat or by using vacuum evaporation techniques.
4. Crystallization: As the brine becomes more concentrated, sodium chloride begins to crystallize out of the solution. This crystallization process can occur spontaneously under controlled conditions, or it may be induced through seeding the solution with tiny salt crystals.
5. Separation: Once the salt crystals have formed, they are separated from the remaining liquid. This can be done by filtration, centrifugation, or other separation techniques.
6. Drying: The separated salt crystals are then dried to remove any remaining moisture, resulting in solid sodium chloride, which is commonly known as table salt.

This process is widely used in industrial settings to produce sodium chloride from brine on a large scale.