Chemistry

Atoms

• The term 'atom' was introduced by Ostward. 
• Atoms are the tiny particles of which everything is made. 
• The first atomic theory was postulated by John Dalton in 1808. 
• The nuclear model of atom was first proposed by Rutherford. 
• The term molecule was introduced by Amadeo Avogadro. 
• The simplest Atom is Hydrogen. 
• Mass number is the sum of numbers of protons and neutrons presenting the nucleous of an atom. 
• The smallest atom known is helium. 
• Anode rays are discoverd by Eugene Goldstein 
• Cathode rays are used in Television. 
• The radioactive gaseous element is radon. 
• The radioactive liquid element is francium. 
• The most valid atomic theory is " wave mechanical model of atom " suggested by Max plank.