Question

why is sea water salty.

Answer 1

Sea water contains salt because as rainwater dissolves minerals as it passes through the soil and percolates through rocks. hence its salty 

Answer 2

Seawater is salty because it contains a large amounts of different salts in it. When you evaporate seawater there are a bunch of different types of salt and minerals. basically it more contains nacl it is used in common salt but in this there are more paticles of na2 and cl2 thus it is dangerous also