Question

section c se biology start hai section c se pahle chemistry hai.question number dal ke answer dijeye ga. ​

Answer 1

iii)

a)mercury

b)Sodium and Potassium

7)

i)Sodium is a very reactive metal. It is kept in kerosene to prevent it from coming in contact with oxygen and moisture because if come in contract oxygen and moisture it catch fire.

ii)

a) Mineral: The naturally occurring compounds of elements are known as Mineral.

b)Gangue: The impurities present in the ore such as sand, rocks etc are non as gangue.

8)Metals refers to the natural elements that are hard, shiny, opaque and dense. Non-metals implies those chemical substances that are soft, non-shiny, transparent and brittle. Most metals are hard, except sodium. Most non-metals are soft, except diamond.