1. CATEGORIZE ELEMENTS AS METALS, NONMETALS, METALLOIDS AND NOBLE GASES.
RECOGNIZE PERIODIC TRENDS OF ELEMENTS, INLCUDING THE NUMBER OF VALENCE ELECTRONS, ATOMIC SIZE AND REACTIVITY.
CATEGORIZE ELEMENTS AS METALS, NONMETALS, METALLOIDS AND NOBLE GASES.
DIFFERENTIATE BETWEEN FAMILIES AND PERIODS.
USE ATOMIC NUMBER AND MASS NUMBER AND MASS NUMBER TO IDENTIFY ISOTOPES.
COS 1.0, 1.1, 1.2, 1.3

2. WHAT YOU’LL LEARN
State the charge, mass, & location of each part of an atom according to the modern model of the atom.
Relate the organization of the periodic table to the arrangement of electrons within an atom.
Identify isotopes of common elements.
Determine how many protons, neutrons, & electrons an atom has, given its symbol, atomic number, & mass number.
Locate alkali metals, alkaline earth metals, & transition metals in the periodic table.
Locate semiconductors, halogens, & noble gases in the periodic table.

3. ATOMIC STRUCTURE

4. WHAT ARE ATOMS?
smallest part of an element that still has element’s properties.
building blocks of molecules

5. WHAT’S IN AN ATOM?

6. NUCLEUS
center of each atom
small & dense
has positive electric charge

7. PROTONS
subatomic particle that has positive charge
found in nucleus

8. NEUTRONS subatomic particle that has no charge
no overall charge because of equal number of protons and electrons whose charges exactly cancel

9. ELECTRONS subatomic particles with negative charges.
located in a cloud moving around outside nucleus

10. QUARKS
particles of matter that make up protons and neutrons

11. MODELS OF THE ATOM

12. DEMOCRITUS Greek philosopher developed theory around 400 B.C.
proposed that atoms make up all substances
Atom — “unable to be divided”

13. JOHN DALTON atomic theory developed in 1808
first atomic theory with a scientific basis
model was simple sphere
thought the atom could not be split

14. NIELS BOHR theory developed in 1913
Bohr suggested that electrons in an atom move in set paths around the nucleus much like planets orbit the sun in our solar system
It is impossible to determine an electrons?
exact location of an electron
speed
direction
Best scientists can do is?
calculate chance of finding an electron in a certain place within an atom

15. ENERGY LEVELS
path of a given electron's orbit around a nucleus, marked by a constant distance from the nucleus
Closer to nucleus, lower energy level of electrons
Further from nucleus, more energy electrons have
Number of filled energy levels an atom has depends on number of electrons

16. ORBITAL
region in an atom where there is a high probability of finding electrons

17. VALENCE ELECTRONS found in outermost shell of an atom
determines atom’s chemical properties
participate in chemical bonding
Every atom has between one and eight

18. THE PERIODIC TABLE

19. ORGANIZATION OF THE PERIODIC TABLE
Groups similar elements together
organization makes it easier to predict properties of an element based on where it is in periodic table
Elements are listed in order of number of protons

20. PERIODIC LAW
states that when elements are arranged this way, similarities in their properties will occur in a regular pattern
helps determine electron arrangement

21. PERIODS Horizontal rows
number of protons & electrons increases as you move from left to right

22. FAMILY/GROUP vertical column of elements
Atoms of elements in same group have same number of valence electrons
elements have similar properties

23. IONS
an atom or group of atoms that has lost or gained one electron and has a negative or positive charge

24. HOW THE STRUCTURES OF ATOMS DIFFER

25. ATOMIC NUMBER (Z)
number of protons in the nucleus

26. MASS NUMBER (A)
number of protons plus the number of neutrons in nucleus

27. ATOMIC RADIUS is size of atom GROUPS
radius increases as one proceeds down any group of periodic table
WHY?
adding layers of electrons
PERIODS
radius decreases as one proceeds across any row of periodic table
increasing number of protons in nucleus as you go across the period pulls electrons in more tightly.

28. ISOTOPE
has same number of protons as other atoms of same element do but has a different number of neutrons.
Some are more common than others.
If you know the atomic number and mass number of an atom, you can calculate the number of neutrons it has.

29. Example
Chlorine 35 has a mass number of 35. Has an atomic number of 17.
Mass number (A): 35
Atomic number (Z): –17
Number of neutrons: 18

30. AVERAGE ATOMIC MASS
weighted average of masses of all naturally-occurring isotopes of an element

31. FAMILIES OF ELEMENTS

32. HOW ARE ELEMENTS CLASSIFIED?
By similar physical & chemical properties.

33. BASIC PROPERTIES

34. LUSTER
ability to reflect light

35. CONDUCTIVITY
ability to conduct heat or an electric current

36. MALLEABILE
Ability to be hammered or rolled into thin sheets

37. DUCTILE
Ability to be stretched/drawn into a thin wire

38. METALS
three categories

39. ALKALI METALS located in group 1 of periodic table shiny malleable
ductile
React violently w/ water
Very reactive b/c it has only one valence electron
Has +1 charge
Not found in nature as elements
Found only in compounds
Ex: salt (NaCl)
Lithium
used to treat bipolar disorder

40. ALKALI EARTH METALS located in Group 2 of periodic table
Has two valence electrons
Has +2 charge
shiny
malleable
ductile
Form compounds in stone & human body
Calcium (Ca):
Shells of sea animals, coral reefs (limestone), skeletal structure humans …
Magnesium (Mg)
Air plane construction
Activates enzymes that speed up processes in humans
brilliant white color in fireworks
Medicines
milk of magnesia
Epsom salt

41. TRANSITION METALS located in groups 3-12 most familiar
found in elemental state
Iron
most abundant metal
used in steel
Aluminum
making containers, automotive parts, cookware…
MERCURY
only metal at room temperature
used in thermostats, thermometers, batteries …

42. ALLOY
COMMON ALLOYS
mixture of a metal with one or more elements that retains original properties of metal
NAME
COMP.
USE
bronze
Copper, tin
Jewelry marine hardware
Brass
Copper, zinc
Hardware musical instruments
Sterling silver
Silver, copper
Tableware, jewelry

43. NONMETALS
Some elements found in groups & all elements in groups 17-18
except hydrogen
usually gases or brittle solids at room temperature
poor conductor of heat & electricity
may be solids, liquids, or gases at room temperature.

44. HALOGENS located in Group 17 very reactive in elemental state Chlorine
greenish yellow gas
Kills bacteria
Elemental chlorine is very poisonous
obtained from seawater
Fluorine
Poisonous yellow gas
used in toothpaste
Bromine
Dark red liquid
only nonmetal liquid at room temperature
Iodine
shiny, purple-gray solid
Used as disinfectant

45. NOBLE GASES located in group 18
Exist only as single atoms instead of molecules
Unreactive b/c orbitals are full of electrons
Neon
Signs
Helium
Less dense than air
Gives lift to blimps & balloons
Argon/Krypton
Used in light bulbs

46. SEMICONDUCTORS
elements that can conduct electricity under certain conditions
Aka metalloids:
Composed of only six elements
Boron, silicon, germanium, arsenic, antimony & tellurium
Boron
Extremely hard
Added to steel to increase hardness & strength at high temperatures.
Antimony
Used as fire retardants
Silicon
Makes up 28% of earths crust
Sand most common compound
Used in electronics