ATOM AND MOLECULE, class 9 notes
ATOM AND MOLECULE The idea of divisibility of matter was considered around 500 BC india. Maharishi Kanad (Indian philosopher) postulated that if we go on dividing matter ( padarth ) in smaller particle so that further division will not be possible. This smallest particle is known as pramadu . Pakudha Katyayama (Indian philosopher): said that these particles normally exist in a combined form and form different forms of matter. Democritus and Leucippus (Greek philosophers) according to them if we divide matter, a stage will come when particles obtained cannot be divided further. Democritus called these indivisible particles atoms (meaning indivisible). · Antoine L. Lavoisier laid the foundation of chemical sciences Law of Chemical Combination two laws is Given by Lavoisier and Joseph L. Proust as follows: 1. Law of conservation of mass: Mas...