What are the three major chemicals that are commercially obtained from sea water? (a) Sodium chloride, calcium carbonate, sodiumsulphate (b) Sodium chloride, magnesium and bromine (c) Sodium chloride, calcium chloride, calcium carbonate (d) Sodium chloride, sodium bromide, sodium carbonate

Sodium chloride, commonly known as table salt, is among the most abundant minerals extracted from seawater. This versatile compound has a range of uses from seasoning and preserving food to industrial applications such as in the manufacture of plastics and paper.

To obtain sodium chloride from seawater, the water is generally placed in large, shallow ponds where the Sun’s heat evaporates the water, leaving behind salt crystals. This process, known as solar evaporation, is one of the oldest methods of salt production and is still widely used today due to its simplicity and cost-effectiveness.

Salt extracted from the sea differs slightly from rock salt, which is mined from the Earth, in terms of mineral content and texture, but essentially both forms are predominantly sodium chloride. The sea salt typically retains trace amounts of other minerals found in seawater which can provide subtle flavors and variations in color.

Magnesium is a lightweight metal with strong structural properties, making it highly sought after for various applications. Its demand spans from the production of lightweight components in the automotive and aerospace industries to its use in the manufacturing of electronic devices and fireworks.

The extraction of magnesium from seawater is a more complex process than that of sodium chloride. It involves several steps including the precipitation of magnesium hydroxide from seawater by adding lime (calcium hydroxide). Subsequently, the magnesium hydroxide is converted to magnesium chloride and then it undergoes electrolysis to produce pure magnesium metal.

Given that the Earth's oceans are a vast source of magnesium, this method of extraction offers an almost unlimited supply of the metal. However, the extraction process must be efficient and environmentally sustainable as the production involves high energy consumption and can have substantial ecological impacts if not managed properly.

Bromine is a dark reddish-brown liquid at room temperature and is another valuable chemical obtained from seawater. Its uses are diverse, featuring prominently in the pharmaceutical industry where it's an essential component for the synthesis of a variety of drugs.

In addition to the pharmaceutical applications, bromine compounds are vital in the production of flame retardants used in electronics, textiles, and furniture to ensure safety and compliance with fire regulations. Bromine is also used in the manufacturing of pesticides, water treatment chemicals, and photographic chemicals.

The extraction process of bromine from seawater is generally performed by bubbling air through the water to release bromine, which is then converted into bromine compounds. Given its wide range of applications, especially in sectors concerned with health and safety, bromine remains a significant product of seawater extraction.