Name the major salt which is present in sea-water.

The major salt present in seawater is sodium chloride (NaCl), commonly known as table salt. Here’s an explanation of its significance and composition:

Explanation:
Composition of Seawater:

Seawater contains various dissolved salts, with sodium chloride being the most abundant. On average, seawater has a salinity of about 3.5%, meaning there are approximately 35 grams of dissolved salts per liter of seawater.
Other dissolved salts include magnesium sulfate (MgSO₄), calcium carbonate (CaCO₃), potassium chloride (KCl), and others, but sodium chloride constitutes about 85% of the total dissolved salts.
Source of Sodium Chloride:

Sodium chloride originates from the weathering of rocks and minerals on land. Rivers carry these dissolved ions to the oceans.
It can also form through evaporation processes in shallow seas and salt flats, concentrating the salts in the remaining water.
Importance:

Sodium chloride is crucial for marine life as it helps regulate osmotic balance in organisms.
It plays a vital role in various chemical processes, including those in biological systems.
The presence of NaCl contributes to the taste of seawater and is essential for many human activities, including food preservation and seasoning.
Summary:
In summary, sodium chloride (NaCl) is the major salt in seawater, making it a significant component of the ocean's chemical makeup and vital for marine ecosystems.