WELCOME

POWER POINT PRESENTATION BY

ANUPARVATHY A

PHYSICAL SCIENCE

EMMANUEL COLLEGE

OF

B.ED TRAINING

FUNDAMENTAL CONSTITUENTS OF SUBSTANCE –ATOM

RECALL……….

• MOLECULES IS THE SMALLEST PARTICLE OF A PURE SUBSTANCE

• MOLECULES ARE MADE UP OF SMALLER COMPONENTS CALLED ATOM

• IN THE MOLECULES OF A SUBSTANCE, IF THERE ARE ONLY TYPE OF ATOMS, THEN THAT SUBSTANCE IS CALLED AN ELEMENT

• SUBSTANCE MADE OF ATOMS OF DIFFERENT ELEMENTS ARE COMPOUNDS.

ATOM• THE BASIC UNIT OF ALL SUBSTANCES. THE WORD ‘ATOM' ORIGINATED FROM LATIN WORD ‘ATOMOS’ WHICH MEANS “THAT CANNOT BE DIVIDED

• THE ANCIENT GREEKS WANTED TO LEARN ABOUT THE SMALLEST PARTICLE OF MATTER.

DEMOCRITUS

ARISTOTLE

DEMOCRITUS

• BELIEVED THAT ALL MATTER CONSISTED OF EXTREMELY SMALL PARTICLES THAT COULD NOT BE DIVIDED.

• HE CALLED THERE PARTICLES ATOM

ARISTOTLE• HE DID NOT THINK THERE WAS A LIMIT TO THE NUMBER OF

TIMER MATTER COULD BE DIVIDED

• HE THOUGHT THAT ALL SUBSTANCE WERE BUILT UP FROM ONLY FOUR ELEMENTS.

• EARTH, AIR, FIRE, WATER

IS ATOM DIVISIBLE ………..?DALTON’S THEORY SAYS ‘NO’.

INVESTIGATION INTO THE STRUCTURE OF MATTER LED THEM TO THE ATOMIC THEORY.

JOHN DALTON• THE PROPOUNDER OF ATOMIC THEORY IN MODERN PERIOD.

• THE ATOMIC THEORY PUT FORWARD BY JOHN DALTON IN 1808 WON THE RECOGNITION FOR THE ATOM AS A FUNDAMENTAL CHEMICAL PARTICLE.

POSTULATES OF DALTON’S ATOMIC THEORY

• ALL MATTER IS MADE UP OF SMALL PARTICLES CALLED ATOMS.

• ATOM IS THE SMALLEST PARTICLE WHICH CAN ENGAGE IN A CHEMICAL REACTION.

• ALL ATOMS OF AN ELEMENT HAVE THE SAME PROPERTIES THAT IS THEY HAVE SAME MASS, SIZE AND CHARACTER.

• ATOMS OF DIFFERENT ELEMENT HAVE DIFFERENT CHARACTERISTICS

• ATOMS CAN NEITHER BE CREATED NOR DESTROYED

• ATOMS ARE INDIVISIBLE.

THANK YOU