Question

Which is the substance obtained on a commercial scale from
sea water, besides sodium chloride?

Answer 1

The seawater gives huge amounts of salt on the commercial basis, as this water is full of sodium chloride or common salt.

Another substance that is commercially available from seawater is the sea fish that is a favorite eatable across the world.

There are numerous varieties of sea fishes, prawns and other creatures that captured in large quantities from the seas and sold in the markets worldwide.

Answer 2

Explanation:

Sea water is rich in different minerals mainly in the chlorides of sodium and magnesium. The extraction of sodium chloride from sea water is one of most common method for the preparation of sodium chloride.  

Besides sodium chloride, magnesium chloride is another important salt which is extracted from the sea water. Magnesium chloride which is formulated as $\bold{\mathrm{MgCl}_{2}}$ is one of the most common ore for the extraction of magnesium metal.