Write a short note: Earth – Treasure of elements.

Earth is a treasure of elements as different elements are obtained directly or indirectly from:

i) Lithosphere: It is the part of the earth formed of sand, clay and stone, in which metal elements like aluminium, copper, iron, calcium, sodium, zinc etc. are in the forms of oxide, sulphide or carbonate.

ii) Hydrosphere: It is the mostly liquid part of the earth water of seas, rivers, lakes and the ice of polar region. In this part of region non-metals such as chlorine, fluorine and metals like sodium, potassium, calcium, etc. are found in combined forms.

iii) Atmosphere: The cover of gases around the earth is called atmosphere. Non-metallic gases such as nitrogen, oxygen, carbon dioxide, etc. are present.