Ch 2 - Elements + The Periodic Table

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Ch 2 - Elements +
The Periodic Table
Chemical Symbols
 Always start with:
 Can be ___ or _____ letters
Periodic Table:color code
your table!
Metals, Non-metals,
Metalloids
 Fill in the
graphic
organizer to
record the
basic
properties of
groupings on
the periodic
table!
Metals
Metalloids
Properties:
Non-metals
Properties:
Properties:
STP state:
STP state:
STP state:
Appearance:
Appearance:
Appearance:
Conductiv ity :
Conductiv ity :
Conductiv ity :
Malleability :
Malleability :
Malleability :
Ductility :
Ductility :
Alkali metals: a.k.a. Group 1
Ductility :
Halogens: a.k.a. Group 17
Elements:
Elements:
Key f eatures:
Key f eatures:
Common uses:
Common uses:
Other:
Other:
Alkaline earth metals: a.k.a. Group 2
Noble gases: a.k.a. Group 18
Elements:
Elements:
Key f eatures:
Key f eatures:
Common uses:
Common uses:
Other:
Other:
READING
the
TABLE
 Atomic #
Tells us:
Atomic Mass
Tells us:
Therefore,
The # of
neutrons =
Practice:
NEUTRAL Atoms of the Ele ments!
Name
Symbol Atomic Atomic
#
Mass
Bromine Br
35
80 amu
Manganese Mn
25
55amu
Gold
Au
79
197
Aluminum Al
13
27
Lead
Pb
82
207
# of
protons
35
25
79
13
82
# of
electrons
35
25
79
13
82
# of
neutr ons
45
30
118
14
125
Do the Atomic Structure
Worksheet
Name of
Element
Symbol of
Element
Atomic
Number
Atomic
Mass
Number
of Protons
Number
of
Electrons
K
35
Al
Li
12
8
Ni
10
18
Gold
11
Pb
Number
of
Neutrons
Name of Element
Symbol
Atomic
Number
Atomic
Mass
Number
of Protons
Number
of
Electron
Number
of
Neutrons
Potassium
K
19
39
19
19
20
Bromine
Br
35
80
35
35
45
Aluminum
Al
13
27
13
13
14
Lithium
Li
3
7
3
3
4
Magnesiu
m
Oxygen
Mg
12
24
12
12
12
O
8
16
8
8
8
Nickel
Ni
28
59
28
28
31
Neon
Ne
10
20
10
10
10
Argon
Ar
18
40
18
18
22
Gold
Au
79
197
79
79
118
Sodium
Na
11
23
11
11
12
Lead
Pb
82
207
82
82
125
Chemical Formulas
 tell you which elements are
present in a compound, and their
amount
 Each new element is denoted by a
CAPITAL LETTER.
 NaCl = sodium and chlorine
 MgBr =magnesium and bromine
 The subscript (the small number
slightly below the line) tells you
how many atoms are present –
that number only applies to the
element at the immediate left of
the number.
 Ex. H2O = 2 hydrogen atoms
1 oxygen atom
 CaCl2 =
1 calcium atom
2 chlorine atoms
 Coefficients are large numbers
written in front of the compound
symbol. This tells you how many
molecules of that compound you
have.
Ex. 5NaNO3 =
5 Na atoms
5 N atoms
15 O atoms
4NH4ClO3 = 4 N
16H
4 Cl
12 O
 Brackets around a complex ion, with a
number to the immediate right of the
brackets, tells you how many of that
complex ions you have in the compound.
That number applies to all elements
inside the bracket.
 Ex. (NH4)2SO4 = 2N, 8H, 1S, 4O
 Ex. 4Ca3(PO4)2 = 4[3Ca 2P, 8O)]
= 12 Ca, 8P, 32O
 Mg(NO3)2 =
1 magnesium atom
2 nitrogen atoms
6 oxygen atoms
 3Ba3(PO4)2 = 9 Barium atoms
6 potassium atoms
24 oxygen atoms
Do the Reading Chemical
Formula Worksheet
Chemical
Formula
Ex. 2NaCl
3N2O3
2KHCO3
5FeSO3
C6H12O6
3K2Cr2O7
CH3COOH
Mg(OH)2
3 Al(OH)3
4CuClO3
Number of
Different
Types of
Atoms
2
Names of
Each atom
present
Number of
each type of
atom
Sodium
Chlorine
2 sodium
2chlorine
Total Number Number of
of Atoms
molecules of
present
this
compound
4
2
Chemical Formula
Ex. 2NaCl
Number of Different
Types of Atoms
2
2
3N2O3
4
2KHCO3
3
5FeSO3
3
C6H12O6
Names of Each atom
present
Sodium
Chlorine
Nitrogen
Oxygen
Potassium
Hydrogen
Carbon
Oxygen
Number of each
type of atom
2 sodium
2chlorine
6N
9O
2
Potassium
2
Hydrogen
2 Carbon
6 Oxygen
Iron
5 Iron
Sulphur
5 Sulphur
Oxygen
15 Oxygen
Carbon
6 Carbon
Hydrogen 12
Oxygen
Hydrogen
6 Oxide
Total Number of Atoms
present
Number of molecules of
this compound
4
2
15
3
12
2
25
5
24
1
Chemical Formula
Number of Different
Types of Atoms
Names of Each atom present
Number of each type of
atom
Total
Number of
Atoms
present
Number of
molecules of this
compound
3
Potassium
Chromium
Oxygen
Carbon
Hydrogen
Oxygen
Magnesium
Oxygen
Hydrogen
Aluminum
Oxygen
Hydrogen
6 Potassium
6 Chromium
21 Oxygen
2 Carbon
4 Hydrogen
2 Oxygen
1 Magnesium
2 Hydrogen
2 Oxygen
3 Aluminum
9 Oxygen
9 Hydrogen
33
3
8
1
5
1
21
3
Copper
Chloride
Oxygen
4 Copper
4 Chloride
12 Oxygen
20
4
3K2Cr2O7
3
CH3COOH
3
Mg(OH)2
3
3 Al(OH)3
3
4CuClO3
Study for Quiz!
 Atomic Structure worksheet
 Reading Chemical Formula
Worksheet
 Models of Molecules
Drawing Bohr
Diagrams of
Atoms
 The nucleus contains all
the protons and
neutrons.
 Consequently, all the
mass is concentrated in
the nucleus. The
electrons are arranged in
specific ORBITALS
around the nucleus.
Orbital Limits
 There is a specific
limit to how many
electrons an orbital
(or shell) can hold.
 Within the orbitals,
the electrons like to
spread themselves
out.
Why Spread out?
 electrons carry negative charges
 negative charges repel
 Electrons fill the orbitals in the following
pattern:
Orbital: 1st
4th
2e-
2nd
3rd
8e-
8e-
Which of these diagrams is incorrect?
What elements are A,B,C,and D
18e-
 Once an orbital is
full, the electrons
will start filling the
next orbital.
 The innermost
orbital (#1) gets
filled first.
Example: Hydrogen
 Atomic # =
1
______
1
 Atomic Mass = ______
1
 # protons = ______
0
 # neutrons = ______
1
 # electrons = ______
Example Lithium
 Atomic # =
3
______
 Atomic Mass = ______
7
 # protons = ______
3
4
 # neutrons = ______
3
 # electrons = ______
Example:
Chlorine
17
______
36
 Atomic Mass = ______
17
 # protons = ______
19
 # neutrons = ______
17
 # electrons = ______
 Atomic # =
Now do the worksheet:
“Models of the elements”
 Definitions:
 1) Valence
Shell: the
outermost
orbital (or
shell)
 2) Valence
Electrons:
_electrons
in the
outside
shell
The Valence
Shell
 The Valence Electrons are involved in
forming bonds with other atoms. The
inner electrons and nucleus are not
involved in bonding.
 Atoms can:
 - _gain valence electrons
 - _lose valence electrons
 - _share valence electrons
 Example: Oxygen
 Atomic # = _8____
 Mass = ___16___
 #p = _8___
 #e = _8___
 #n = _8___
 Combining Capacity: The number of
electrons that an atom must gain or lose
to have a full valence shell.
 Full for 1st shell = _2e-___
 Full for 2nd shell = _8e-___
 Full for 3rd shell = _8e-___
 Will an Atom Gain or Lose Electrons?
 Valence electrons
greater than 4
 less than 4
equal to 4
Gain/Lose?
gain
lose
gain or lose
 exception: HYDROGEN
 This element is unique because it has
the ability to either gain or lose one
electron to “fill” its orbitals.
 Examples: Nitrogen
7
 atomic # = _____
14
 mass = _____
 #p = _7____
 #n = _7____
 #e = _7____
 # valence e = _5____
 Will this atom
gain or lose? __gain_
 How many ? ___3____
 What is its
combining capacity? _3-_
 Charge ? __3-
 When nitrogen is charged it is called
_nitride
 Example 2: Neon
 atomic # = _10____
 mass = ___20__
 #p = __10___
 #n = __10___
 #e = __10___
 # valence e = __8___
 Will this atom gain or lose? __neither___
 How many ? ___0____
 What is its combining capacity? _0_____
 Charge ? __0____
 Atoms with C.C. =_0=_INERT (NOBLE)_
that is , they will not blow up! (or react
at all!)
 Charge:
 Atoms are neutral if #p+ = # e If atoms gain or lose electrons they
become _charged = IONS!_.
Now go back and answer the
questions on the Bohr diagram
worksheets!
 When naming NON-METAL ions,
_change__ the name _ending_ to
“_ide___”
 e.g. _oxygen___ = __oxide_______
 __fluorine___ = _fluoride
 Non-metals form _negative ions.

(_#e- > #p+)
 Metals form _positive_ ions.

(_#e- < #p+)
Study for Bohr Diagrams
Quiz!
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