Different kinds of matter : Different kinds of matter Balls, books, utensils, car…etc
Slide 2 : SSee! How these ants are building their anthill using basic building blocks of sand
k
Mason building a house : Mason building a house Walls---------------? House Bricks----------------?
STRUCTURE OF ATOM : STRUCTURE OF ATOM
What is an atom? : What is an atom? JOHN DALTON gave the name ATOM which means- ‘cannot be divided further’
Atom: the smallest unit of matter that retains the identity of the substance
Slide 6 :
Slide 7 : PARTICLES PRESENT IN AN ATOM 1897-J.J.THOMSON…………..ELECTRONS(---)
1908-ERNEST RUTHERFORD……PROTONS(+)
1932-JAMES CHADWICK………….NEUTRONS(no charge)
Slide 8 :
Slide 9 :
THE STRUCTUREOF ATOM PRESENTED BY RUTHERFORD IS SIMILAR TO THAT OF SOLARSYSTEM : THE STRUCTUREOF ATOM PRESENTED BY RUTHERFORD IS SIMILAR TO THAT OF SOLARSYSTEM SOLAR SYSTEM
CENTRE…….SUN
PLANETS…..REVOLVE ROUND THE SUN
ORBIT….PATH THROUGH WHICH PLANETS MOVE ATOM
CENTRE…….NUCLEUS
ELECTRONS….REVOLVE ROUND THE NUCLEUS
ORBIT……PATH OF ELECTRONS REVOLVING ROUND THE NUCLEUS
Slide 11 : P N E P N E -- PROTON
--NEUTRON
--ELECTRON *7
Atomic Structure : Atomic Structure Atoms are composed of 2 regions:
Nucleus: the centre of the atom that contains the mass of the atom
Electron cloud: region that surrounds the nucleus that contains most of the space in the atom Nucleus Electron
Cloud
Slide 13 : What is ATOMIC NUMBER? (Z)
It is the number of PROTONS(+ve chargedparticles) present in an atom!
Since it is equal to the no. of electrons,
ATOMIC NUMBER= No. of -------- / No. of ---------
SYMBOL OF ELEMENT
ATO.NO C 6
Slide 14 : What is ATOMIC MASS ? (M)
It is the number of {PROTONS+NEUTRONS } present in an atom!
ATOMIC MASS == No. of ------- + ------
ATO MASS
SYMBOL OF ELEMENT Eg: C 12 C 12
Slide 15 : LOOK AT THESE ------
HOW TO REPRESENT ATOMIC NO. & ATOMIC MASS
IN THE SYMBOL OF AN ELEMENT
How do the subatomic particles balance each other? : How do the subatomic particles balance each other? In an atom:
The protons = the electrons
If 20 protons are present in an atom then 20 electrons are there to balance the overall charge of the atom—atoms are neutral
The neutrons have no charge.
Slide 17 : GREAT PAPA SMALL PAPA Protons (atomic number) --------- ------- -----
Neutrons ------ ------
Electrons ------ ------
Protons+neutrons (atomic mass) ------- --------
Slide 18 : Have a look at them- Atomic no mass no P N E = ---- ---- -- -- -- = ---- ---- -- -- -- Hint- Ato no=no. of P/E & mass.no=no. of P+N 7N 14 8O16
Slide 19 : Have a look at them-
32 Ce76 Atomic no mass no P N E = ---- ---- -- -- -- 34Se76 = ----- ---- -- -- -- Hint- Ato no=no. of P/E & mass.no=no. of P+N
Slide 20 : 1) 26Fe58 Atomic no mass no. P N E ----- ---- --- --- --- 2) 27Ni58 ---- ---- --- --- ---