1. The Atom
Prepared by: Timothy John D. Matoy

2. The Atom
The atom is the smallest particle that has all the properties of an element.

3. Greek atom

4. Dalton Atom
1808
An element is composed of atoms that reacted the same way chemically.
eye and hook affair – physical combinations
1808
An element is composed of tiny indivisible sphere, indestructible particles called atoms
All atoms of an element are identical and have the same properties
Atoms of different elements combine to form compounds.

5. 1890 ThomPson Model 1890 Atom is electrically neutral
Electrons where electrons are uniformly disperse is homogenous positively, charge spheres

6. Rutherford Model
1911
Ernest Rutherford - disproved thomson. Containing small dense, positively charged center with electron cloud. 1911
-1023 cm in diameter.. ball and marble
-also estimates the size of the atom

7. Bohr Model
1913
Neil Bohr in miniature solar system, improved Rutherford
Speculated that in the atom, electron revolve around the nucleus, occupying circular orbits w/ distinct energy levels 2n

8. Atomic Structure Quarks and gluons Atomic mass number
Atomic number = determined by the number of protons
Atomic Weigh or mass = determined by measurement and rarely a whole number.
Atomic mass number = neutrons + protons symbolized by A
Electron binding energy – the strength of the attachment to the electron to the nucleus.
zXA z = atomic number A = mass number

9. zXA Where: z = atomic number X = chemical Symbol A = Mass number
Atomic Notation
zXA
Where: z = atomic number
X = chemical Symbol
A = Mass number

10. Atomic Notation
Atomic Number (Z) – The number of proton in the nucleus or the number of electrons in neutral atom Mass Number (A) – The number of protons and neutrons in an atom Therefore: A – Z = the mass of neutrons in the nucleus.

11. Isotopes of Carbon Carbon-12 Carbon-13 Carbon-14 PRACTICE PROBLEM
Mass #
# of Protons
# of Neutrons
# of electrons
Carbon-12
Carbon-13
Carbon-14

12. NUClear stability
Unstable atoms have excess energy in the nucleus. They will give off their energy until they reach a stable ground state.
Periodic table
Valence shell electrons

13. Valence electrons - explain
Demtri mendeleev

15. Some Significant element in the Radiological field with their atomic number
H – 1 He – 2 Be – 4 C – 6 N – 7 O – 8 F – 9 Na – 11 Mg – 12 Al – 13 P – 15 Ca – 20 Co – 27 Cu - 29 Ba – 56 W - 74

16. Isotopes Isotones Isobars isomers
Atomic Nomenclature
Isotopes Isotones Isobars isomers
Isotopes – the same atomic number but different atomic mass number
Isobar – same atomic mass number but different atomic numbers
Isotone – the same number of neutrons
Isomer – the same atomic number and the same atomic mass number differ in chemical structure

17. ISOTOPES
Atoms having the same number of protons but a different number of neutrons. example: 6C12 6C14

18. Same number of neutrons and different number of protons.
ISOTONES
Same number of neutrons and different number of protons.
They are different element

19. ISOBARS
Atoms having the same number of nucleons (same atomic mass number) but different number of protons and neutrons. Example: 5B11 6C11

20. Isomers
Atoms having the same number of protons and neutrons (therefore the same element) but have different nuclear energy levels.
Atoms having the same number of protons and neutrons (therefore are the same element) but have different nuclear energy levels
Different energy levels due to excess energy in the nucleus
Energy is released in form or photon
Excess energy is released in 140 keV
Metastable state of half-life is long enough
Energy is released in form of photon (Technetium is used in nuc. Med. Has hal-life of 6 hours.

21. Isomers
Atoms having the same number of protons and neutrons (therefore are the same element) but have different nuclear energy levels
Different energy levels due to excess energy in the nucleus
Energy is released in form or photon
Excess energy is released in 140 keV

22. Molecules Atom combine to form a molecule
Smallest particle of an element is atom
Smallest particle of a compound is molecule

23. Nuclear Force Electromagnetic Force Gravitational Force
Basic Forces in Nature
Nuclear Force Electromagnetic Force Gravitational Force

24. Nuclear Force

25. Electromagnetic Force

26. Gravitational Force