The origin of paper dates back to the early Egyptian civilisation. The Egyptians used the stalks of the papyrus plant to manufacture a material resembling paper. Over the centuries several changes have been made and many new materials have been used in the paper making process, but the base of most paper is still fibre from plants.
MODERN DAY PAPER : Today the finest of papers are produced all over the world. But one dismaying fact is that millions of trees are felled in a day to make...
Gold is very special metal. Its chemical symbol is Au with atomic number 79. It is a dense, Yellow, precious, Ductile and Malleable metal used ( as chlonide compound ) for medicinal pues also in the treatment of rheumatoid arthritis. Pure gold is 24 carats. It is too malleable to be used so, it is mixed with copper ordinary jewellary are 22 carats. 24 carats is a 100 % gold and 12 carats is 50% pure. It is alloyed with silver to be used in dental cavity fillings. It has valuency 1 & 3.
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