Chemistry is the branch of chemistry that deals with study of matter.

1. LEARN CHEMISTRY

2. FUNDAMENTALS OF CHEMISTRY

3. DEFINITION
The branch of SCIENCE deals with the
composition, structure, properties
and reaction of matter is called
chemistry.

4. ELECTRON
PROTON
NEUTRON
MATTER
ATOM
composition

5. 1.Atomic model (1808)
2.Plum-pudding model
(1904)
3. Nuclear model
(1911)
4. Planetary model
(1913)
5.Quantum
mechanical model
(1926-present)
+ +
+
_
_
_

6. Plum-pudding model: J.J. Thomson
1.An atom is electrically neutral. It has no charge.
2.In an atom, both positive charges and negative charges are
equal.
3.An atom is made out of a sphere of positive charges with
negatively charged electron embedded in it.
e - e
e - e
e - e -
e -
structure

7. Nuclear model: Ernest Rutherford
1.Atoms are mostly empty space.
2.Most of the mass is concentrated in the center of atom. This
tiny, dense, positively charged core called a nucleus.
3.Electrons are located outside the nucleus. e e
e
structure

8. Planetary model: Niels Bohr
1.Electrons orbit the nucleus in orbits that have specific size and
energy.
2.The energy of the orbit is related to its size. The lowest energy
is found in the smallest orbit.
3.Electrons reside in orbits. They move between each shell when
gaining or losing energy.
4.When gaining energy, electrons move to farther orbit from the
nucleus. When losing energy, electrons move to closer orbit
from the nucleus.
structure

9. Quantum Mechanical Model: Erwin Schrödinger
1.Electrons don’t move around the nucleus in orbits.
2.Electrons exist in specific energy levels as a cloud.
3.The electron cloud is the region of negative charges, which
surrounds the nucleus.
4.Orbital : The region with a high probability of containing
electrons.
structure

10. properties

11. properties

12. CHEMICAL CHANGE PHYSICAL CHANGE