UPSC 2015 CDS I GK Paper

Dalton proposed that atom is indivisible. Dalton’s atomic theory is:
(1) All matter is made of atoms. Atoms are indivisible and indestructible.
(2) All atoms of a given element are identical in mass and properties.
(3) Compounds are formed by a combination of two or more different kinds of atoms.
(4) A chemical reaction is a rearrangement of atoms