1. Properties of Atoms and the Periodic Table

2. Atoms Unit of all matter, building blocks of elements
Smallest piece of matter that has the properties of the element
Make up elements, which combine to make up compounds

3. Elements
Elements are abbreviated in scientific shorthand – first letter or two of element’s name

4. Latin Names Element Symbol Latin name Copper Cu cuprum Gold Au aurum
Lead Pb plumbum
Mercury Hg hydrargyrum
Potassium K kalium
Silver Ag argentum
Sodium Na natrium
Tin Sn stannum

5. Organic Element
Trace Metal

6. Example

7. Compounds
Def: two or more elements combined, pure substance.

8. Example

9. Example 2

10. Example 3

12. Structure of the Atom
Nucleus:
Protons
Neutrons
Electrons

13. Atomic Structure

14. Protons Much larger and heavier than electrons
Protons have a positive charge (+)
Located in the nucleus of the atom 

15. Neutrons Large and heavy like protons
Neutrons have no electrical charge
Located in the nucleus of the atom 

16. Electrons Tiny, very light particles
Have a negative electrical charge (-)
Move around the outside of the nucleus

17. Subatomic Particles Particle Symbol Charge Relative Mass
Electron e
Proton p
Neutron n

18. Atomic Structure
10-13 cm
10-8 cm

19. Atom Models Scientist use scaled-up models to represent atoms.
Early models of atoms used a solid sphere
Current electron cloud model shows electrons traveling in specific energy levels around a nucleus of protons and neutrons.

20. Early Model

21. Electron Cloud Model Example 1

22. Electron Cloud Model: Example 2

23. Masses of Atoms
(1) Atomic Mass
(2) Isotopes
(3) Ions

24. Atomic Mass
Definition: Composed mostly of the protons and neutrons in the nucleus.
Unit of measurement for atomic particles is atomic mass unit (amu), which is 1/12 the mass of a carbon atom.
Atomic Number: this is also the number of protons in an atom
Mass Number: The sum of the number of protons and neutrons in the nucleus of an atom

25. Atomic Number on the Periodic Table11 Na
Atomic Number
Symbol

26. Proton Number identifies an Element11 Na
11 protons
Sodium

27. Reading Elements on the Periodic Table
Mass number = number of protons + number of neutrons

28. Quick Check A. Nitrogen 1) 5 protons 2) 7 protons 3) 14 protons
B. Sulfur
1) 32 protons 2) 16 protons 3) 6 protons
C. Barium
1) 137 protons 2) 81 protons 3) 56 protons

29. Calculating Subatomic Particles
O P Zn
8 p p+ 30 p+
8 n 16 n 35 n
8 e e e-

30. Isotopes
Definition: Atoms of the same element with different numbers of neutrons

31. Isotopes

32. Isotopes Different isotopes have different properties
The number of protons for a given atom never changes.
The number of neutrons can change. 
Two atoms with different numbers of neutrons are called isotopes

34. Isotopes of Chlorine
35Cl 37Cl
chlorine chlorine - 37

35. Quick Check
Naturally occurring carbon consists of three isotopes, 12C, 13C, and 14C. State the number of protons, neutrons, and electrons in each of these carbon atoms.
12C C 14C
#p _______ _______ _______
#n _______ _______ _______
#e _______ _______ _______

36. Answer Key
12C C C #p #n #e

37. Quick Check An atom of zinc has a mass number of 65.
A. Number of protons in the zinc atom
1) ) ) 65
B. Number of neutrons in the zinc atom
C. What is the mass number of a zinc isotope
with 37 neutrons?
1) ) ) 67

38. Ions An atom that carries an electrical charge is called an ion
If the atom loses electrons, the atom becomes positively charged (because the number of positively charged protons will be more the number of electrons). Also called Cation
If the atom gains electrons, the atom becomes negatively charged. Called Anion

39. Ions (continued) The number of protons does not change in an ion
The number of neutrons does not change in an ions
So, both the atomic number and the atomic mass remain the same.

40. Ion Illustration
This atom has lost an electron. Now it has one more proton than electron.
One more proton means one more positive charge.
This makes the total charge of the atom POSITIVE.
This atom has gained an electron. Now it has one less proton than electron.
One less proton means one less positive charge.
This makes the total charge of the atom NEGATIVE.

42. The Periodic Table
Elements are organized to their properties in a chart called the Periodic Table.
Elements are arranged in order of increasing atomic number.
Periods – Horizontal Rows
Groups – Vertical Columns

43. Groups Groups share similar properties
Elements of the same group have the same number of electrons in their outermost shell (energy level).
Energy Shells has a maximum number of electrons. Level 1: 2 e-. Level 2: 8 e-.
Each row in the table ends when an outer energy level is filled.

44. Valence and Shells

45. Periods
Horizontal rows of elements that contain increasing number of protons and electrons.
Elements are classified as metals, non-metals, or metalloids.
Elements are synthesized in laboratories all over the world.
Notes: H and He are the building blocks of other naturally occurring elements

46. Trends in the Periodic Table
Metals
Alkali Metals
Alkali Earth Metals
Transition Metals
Other (Rare) metals
Metalloids
Semi-conductors
Non-metals
Halogens
Other Non-metals
Noble Gas

48. Properties of Metals Conduct heat and electricity
Luster – reflect light well
Malleable – can be hammered or rolled into sheets
Ductile – can be drawn into wire
Ionic Bonding – when combined with non-metals
Metallic Bonding – ions are sliding layers and electrons are weakly held

49. Alkali Metals
Group 1: Soft, white, low-density, low-melting, highly reactive metallic elements
Highly reactive with oxygen and water
Uses:
Human Health: sodium, potassium
Photocells
Francium – a radioactive element which breaks down giving off particles and energy

50. Alkali Earth Metals
Group 2: Not found naturally in elemental form; two electrons in outer energy level. Much less reactive than Alkali Metals
Uses:
Strontium and magnesium found in fireworks
Magnesium in vehicles, ladders and bats
Calcium in statues and countertops
Barium in disease diagnoses
Radium formerly used in cancer treatment

51. Transition Metals
Group 3-12: They are characterized by multiple valences, colored compounds, and the ability to form stable complex ions.
Often occur in nature as uncombined elements
Uses:
Chromium – colored compounds, found in rubies and emeralds
Iron – widely used, main ingredient in steel

52. Transition Metals (Continued)
Uses:
Cobalt and nickel – used in some steels
Nickel – used to coat other metals
Copper – used in electric wiring
Silver – used in photographic film, jewelry
Gold – used in jewelry
Zinc and cadmium – used to coat and plate other metals
Mercury – only room temperature liquid metal

53. Other / Rare Metals
Any metal that is difficult to extract from ore and is rare and expensive commercially

54. Properties of Metalloid
Between Metal and Non-metal
Greek metallon = "metal“ and eidos = "sort".
Form ionic and covalent bonds
Have some metallic and some non-metallic properties
Partial conduction give them “semiconductor” characteristics.

55. Semi-conductor
Silicon in particular, which conducts electricity under certain conditions
Computer chips and other electronic devices.

56. Properties of Non-Metals
Usually gases or brittle solids at room temperature
Not malleable or ductile
Poor conductors of heat and electricity
Usually not lustrous (shiny)
Form ionic bond when combined with metals
Form covalent bond with another non-metal

57. Hydrogen Most common element in the universe Diatomic molecule - H2
Highly reactive element found mostly on Earth as part of water compound

58. Halogen
Group 17: Pure halogens exist as diatomic molecules, and they are highly reactive with Alkali Metal to form salt.
Examples: bromine, iodine, fluorine, chlorine.
Uses:
Chlorine – disinfectant and bleach
Bromine – dyes in cosmetics
Iodine – hormone regulation, disinfectant

59. Noble Gas
Group 18: They are monatomic (isolated) and chemically stable (inert). Also called inert gas.
Uses:
Helium – used in blimps and balloons
Neon, argon, and krypton – used in lights

60. Atomic Radii
Increasing Atomic Radius
Increasing Atomic Radius

61. Atomic Radii
Atomic Radii increase as you go down the group with increasing atomic number.
Atomic Radii decrease as you go across the period with increasing atomic number. As proton number increases from left to right, the attraction to the nucleus becomes greater.
Francium (Fr) is therefore the element with the largest atomic radius.