How do oceanographers define salinity?

The oceanographers define salinity by the number of grams of salt per kilogram of water.  

Salinity is illustrated as how much salt is present in the given amount of water. It is dependent upon how much salt is found in the ocean in the specific regions. If there is a sunny environment, it may evaporate an ample amount of water, and leave behind a lot of salt, thus, the water has more salinity.  

The salinity of the ocean is usually measured in Practical Salinity Unit (PSU), it is a unit based on the characteristics of seawater conductivity.  

answer: -

reaction:

na + cl ⇌ nacl

balanced chemical equation:

na + 2cl ⇌ nacl2

sodium + clorine goes to form sodium chloride (table salt).

the product is nacl2.

and the reactants are na and cl.

(note: if you don’t know what ⇌ means, read below: -

⇌(double head arrow) means reversible reaction).