atoms lose or gain electrons to achieve noble gas electron

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More on Ions
Record into your notes
Achieving Noble Gas
Electron Configuration
An ion forms when an atom
• loses electrons (OIL, oxidation) or gains
electrons (RIG, reduction) to achieve noble
gas electron configuration
Recognize the appearance of Bohr’s Model
after an atom loses or gains electrons to form
ions and/or how two atom share their electrons
covalently to achieve noble gas electron
configuration.
Supplemental packet page 50
Atomic Number:
Name:
sodium-23 ion
23
Symbol:
11
mass #
1+
Na
23
#p
______
11
#n
______
12
#e
11
•••
•• • ••
•••
More protons than
electrons
Electronic
1s2 2s2 2p6 3s0
Configuration:
12
magnesium-24 ion
Name:
24
Symbol:
12
mass #
24
#p
12
______
#n
12
______
#e
10
______
Electronic
Configuration:
Physical Properties:
metal cation
positive ion
1+ charge
Chemical
Properties:
combines w/
anions
Lewis Dot:
______
10
Atomic Number:
Ionic Structure
2+
Mg
•••
•• • ••
•••
More protons than
electrons
[Na]1+
Physical Properties:
metal cation
positive ion
2+ charge
Properties:
combines w/
anions
[Mg]2+
17
Physical Properties:
Name:
Symbol:
•
Chemical
mass #
35
#p
______
#n
______
#e
______
Properties:
Lewis Dot:
Electronic
Configuration:
Atomic Number:
8
Physical Properties:
Name:
Symbol:
•
Chemical
Lewis Dot:
1s2 2s2 2p6 3s0
Atomic Number:
Chemical
mass #
16
#p
______
#n
______
#e
______
Electronic
Configuration:
Properties:
Lewis Dot:
Supplemental packet page 50
Atomic Number:
Name:
sodium-23 ion
23
1+
11Na
Symbol:
mass #
23
#p
______
11
#n
______
12
#e
11
•••
•• • ••
•••
More protons than
electrons
Electronic
1s2 2s2 2p6 3s0
Configuration:
12
magnesium-24 ion
Name:
24
2+
12Mg
Symbol:
mass #
24
#p
12
______
#n
12
______
#e
10
______
Electronic
Configuration:
Physical Properties:
metal cation
positive ion
1+ charge
Chemical
Properties:
combines w/
anions
Lewis Dot:
______
10
Atomic Number:
Ionic Structure
•••
•• • ••
•••
More protons than
electrons
[Na]1+
Physical Properties:
metal cation
positive ion
2+ charge
#n
______
18
#e
______
18
Properties:
combines w/
anions
[Mg]2+
17
1s2 2s2 2p6
Configuration:
Atomic Number:
Name:
8
oxygen-16 ion
16
Symbol:
8
mass #
16
#p
8
______
#n
8
______
#e
10
______
Electronic
Configuration:
Physical Properties:
nonmetal anion
negative ion
1- charge
Chemical
Properties:
combines w/
cations
Lewis Dot:
More electrons than
protons
Electronic
Chemical
Lewis Dot:
1s2 2s2 2p6 3s2
••
chloride-35
ion
Name:
•••
35
1Symbol:
17Cl
•• •• • •• ••
••
•
mass # 35
••
#p
______
17
Atomic Number:
O
2-
•• •Cl• ••
••
[
3s 3p
2
6
•••
•• • ••
•••
More electrons than
protons
1s2 2s2 2p6 3s0
]1-
Physical Properties:
nonmetal anion
negative ion
2- charge
Chemical
Properties:
combines w/
cations
Lewis Dot:
•• •O• ••
••
[
]2-
Please note the movement of the red colored valence (outermost) electron
on sodium. It is transferred over to the fluorine atom.
Bohr Models
Lewis dot structures
Please note the movement of the red colored valence (outermost) electron
on the 1) _______ atom. It is transferred over to the 2) ________ atom.
Fill in the blanks
ANS. 1)Mg, 2)Cl
Record into your notes
Ions isoelectronic (“same electronic configuration”) with noble gases
[Ne]
[Na]1+
•• •Cl• ••
••
[
1s2 2s2 2p6
[Ne]
[Mg]2+
1s2 2s2 2p6
]1-
[Ar]
1s2 2s2 2p6 3s2 3p6
•• •O• ••
••
[
]2-
[Ne]
1s2 2s2 2p6
Please note the addition of the red colored valence (outermost) electrons
to each atom listed. Recognize boron, B, is a semimetal, not a nonmetal.
Draw the following into your notes opposite page 64
nonmetals gain just enough electrons to achieve noble gas
e- configuration of the noble gas in their period (row)
••
•
•
•
•
•
•
•
•
•
••
••
••
••
•
•
• •
• •
• •
•
•
•
•
•
•
•
•
•
•
•
•
•
• •
• •
• •
•
•
•
•
•
••
••
10Ne
5B
6C
8O
9F
N 3–
O 2–
F–
nitride ion
oxide ion
fluoride ion
nonmetals ions
Please Note: the nonmetals like to gain electrons & the stability of these
ions is associated with 8 valence electrons (an octet)
semimetal
C 4–
carbide ion
7N
Chapter 5 - Introduction to Chemical Bonding
Ions isoelectronic (“same electronic configuration”) with noble gases
[Ne]
[Na]1+
•• •Cl• ••
••
[
]1-
[Ar]
]2-
[Ne]
Electrostatic repulsions
Like charges repel
[Ne]
[Mg]2+
Electrostatic attractions
Opposites attract
•• •O• ••
••
[
Ionic Bonding (transferring electrons to achieve noble gas electron configuration)
[Na]1+
•• •Cl• ••
••
[
1.Opposites attract (cation attracts an anion)
2.Brought together by electrostatics
3.Ions coming together to balance charge
]1-
sodium chloride
•• •Cl• ••
••
[ ]
1-
[Mg]2+
•• •Cl• ••
••
[ ]1-
magnesium chloride
[Mg]2+
•• •O• ••
••
[
]2-
magnesium oxide
Looking ahead to Chapter 6
Covalent Bonding (sharing electrons to achieve noble gas electron configuration)
1. Bonding for FONCl BrISCH nonmetals
2. Brought together by sharing of electrons
3. Achieving an OCTET of valence electrons
versus Chapter 5 - Ionic Bonding
Ionic Bonding (transferring electrons to achieve noble gas electron configuration)
1. Opposites attract (cation attracts an anion)
2. Brought together by electrostatics
3. Ions coming together to balance charge
Please note the addition of the red colored valence (outermost) electron
by the in coming hydrogen atom which will be shared by both atoms.
Covalent Bonding (sharing electrons to achieve noble gas electron configuration)
nonmetals bond to hydrogen to achieve noble gas e- configuration
of the noble gas in their period (row)
••
•
•
H
•
•
•
•
• Achieving an OCTET valence
Addition of hydrogen
•
•
H
•
••
••
••
••
•
•
H
H• •
H• •
H• •
•
•
•
•
•
•
•
•
•
•H •
•H •
•H •
•
•
•
•
•
•
•
•
••
••
H•
H
1H
5B
10Ne
7N
6C
CH4
methane gas
NH3
ammonia gas
8O
H2O
water
molecules of nonmetals hydrides
Looking ahead to Chapter 6
9F
HF
hydrogen
fluoride
[Na]1+ Ionic substances
Supplemental packet page 64
Io nic co mpou nds a re he ld together b y stron g el ectrica l fo rces betwe en o ppos itel y cha rged ions (e.g ., Na
, Cl ). Th ese forces a re referred
••
to as ionic bonds . Typ ica lly, i onic compo unds (
ionic salts
) h ave rel ative high mel ting poi nts (mp NaCl = 80 1 °C).and exist
• Cl • 1- ph ys ica lly as sol ids at ro om tempe rature . It ta kes a l ot o f en ergy to brea k a n
io nic bon d. Ca n you give a dditiona l exam ples of ioni c
• • compo unds ?
••
[
+
]
–
Mole cul ar compo unds . Two or mo re atoms may combi ne with on e an othe r to form an u nch arged mol ecu le. The ato ms i nvolved are
un usua lly th ose of n onme tall ic elem ents . Withi n th e mo lecule, ato ms a re he ld to on e an othe r by strong forces call ed
covalent bonds
di atom ic m olecule s - there are
roo m te mpera ture are vari able .
se ven dia tomic
molecules
that beha ve as discrete uni ts. The physi cal sta tes for these mol ecu les at
H H gas
NN
O O
gas
gas
F gas
F
Cl Cl gas
Br Br liquid
I
mo lecules with multiple bon ding patterns
H
molecules of nonmetals hydrides
H C
H
H
N
H
Si H
H
••
P
H
H
••••
H
H
H
S
H
H
H
••••
O
H
H
H
H
••
I solid
H
•• •
•• •
F
•• •
•• •
Cl
Sum mary
What is the favorite charge of these elements as ions? Indicate charge. Is there a relationship
between the type of element that likes to have positive charge? a negative charge?
Li
Be
B
C
N
O
F
ion charge:
1+ 2+ 3+ 4- 3- 2- 1-
How many atoms will each element bond to in order to be stable?
of bonds that each element will make.
Li
number of bonds:
Be
B
C
N
O
Indicate the number
F
1 2 3 4 3 2 1
Is there a relationship between ion charge and the number of bonds an element will make?
If so, describe the relationship.
.
Supplemental packet page 64
H
•• N
N
gas
••
To these molecules,
Add missing
nonbonding pair of electrons
• O• •O•
•gas
• ••
gas
•••F•
••
•••Cl•
••
•••Br•
••
•••I•
••
H
gas
•F• •
gas
•
••
•Cl• •
gas
•
••
•Br• • liquid
• ••
•I• •
solid
•
••
Favorite bonding modes for
nonmetals C, N,O, halogen, H
C
N
O
F
H
•Know the preferred total number
of bonds to these elements
4 3 211
•N O , nitrogen and oxygen may
have variable number of bonds
(2) (1)
(4) (3)
Supplemental packet page 68
valence shell electron
pair repulsion
VSEPR = ________ ________ ________ ________ ________
Dete rmine the ang les betwee n bo nds, nam e th e ge ometry abou t th e centra l atom a nd g ive th e its hybri dizati on.
IdealIdeal
bonding
for carbon = Four bonds to carbon - Four bonding modes
Geometries
109.5
109.5
H C H
bo nd a ngle s
ge ometric name
H
H
120C
C
120
120
H 120 H
109.5 H109.5
H
tetrahedral
180
H
trigonal planar
C
C H
linear
O
180
C O
linear
Ideal bonding angles for carbon
Non-Ideal Geometries
:
:
:
bon d an gles
H
N
H
H107.5
107.5
geo metri c n ame
pyramidal or
trigonal pyramid
N
H
q<120
bent
H
:
O
H
104.5
H
geo metri c n ame
bent
O
:
:
N
N
H
:
bon d an gles
:
N
C
H
Bond angles are less than ideal angle
Electron pair occupies a lot of space &
is held close to nucleus of central atom
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