chemical bonding by julie s.r
TRANSCRIPT
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8/11/2019 Chemical Bonding By Julie S.R.
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Prepared By:
Julie S.R.
Roll No: 9
Physical Science, GCTE, Trivandrum
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Electrons are placed in shells
according to rules:
The 1stshell can hold up to twoelectrons, and each shell thereafter can
hold up to 8 electrons.
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Octet Rule = atoms tend to gain, lose or share electrons soas to have 8 electrons
C would like to
N would like to
O would like to
Gain 4 electrons
Gain 3 electronsGain 2 electrons
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Chemical bonds:an attempt to fill electron shells
1. Ionic bonds
2. Covalent bonds
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IONIC BONDBond formedbetweentwo ions by the
transfer of electrons
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Ionic compoundsresult when metalsreact withnonmetals
Metals loseelectrons to match the number of
valence electrons of their nearest noble gasPositive ionsformwhen the number of electrons
are lessthan the number of protons
Group 1 metals ion 1+
Group 2 metals ion 2+
Group 13 metals ion 3+
Formation of Ions from Metals
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Formation of Sodium Ion
Sodium atom Sodium ion
Na e Na +
2-8-1 2-8 ( = Ne)
11 p+
11 p+
11 e- 10 e-
0 1+
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Formation of Magnesium Ion
Magnesium atom Magnesium ion
Mg 2e Mg2+
2-8-2 2-8 (=Ne)
12 p+ 12 p+12 e- 10 e-
0 2+
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Fluoride Ion
unpaired electron octet
1 -
:F + e : F :
2-7 2-8 (= Ne)
9 p+ 9 p+
9 e- 10 e-0 1 -
ionic charge
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Ionic Bond Between atoms of metals and nonmetals with very
different electronegativity
Bond formed by transfer of electrons Produce charged ions all states. Conductors and have
high melting point.
Examples; NaCl, CaCl2, K2O
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An Example:Formation of NaCl
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Ionic Bonds: One Big Greedy Thief Dog!
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Ionic bond
electron from Na is transferred to Cl, thiscauses a charge imbalance in each atom. The Na
becomes(Na+)and the Cl becomes(Cl-), charged
particles or ions.
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Bond formed by the sharing of electrons
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Covalent Bond Between nonmetallic elements of similar
electronegativity.
Formed by sharing electron pairs Stable non-ionizing particles, they are not conductors
at any state
Examples; O2, CO2, C2H6, H2O, SiC
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Covalent bonds-Two atoms share one or more pairs of outer-shell electrons.
Oxygen Atom Oxygen Atom
Oxygen Molecule (O2)
http://www.usfca.edu/fac-staff/Courses/BIOL104_USF/104_Fall03_ppt/Text%20Chapter%2002/OxgnMol.swfhttp://www.usfca.edu/fac-staff/Courses/BIOL104_USF/104_Fall03_ppt/Text%20Chapter%2002/OxgnMol.swfhttp://www.usfca.edu/fac-staff/Courses/BIOL104_USF/104_Fall03_ppt/Text%20Chapter%2002/OxgnMol.swfhttp://www.usfca.edu/fac-staff/Courses/BIOL104_USF/104_Fall03_ppt/Text%20Chapter%2002/OxgnMol.swfhttp://www.usfca.edu/fac-staff/Courses/BIOL104_USF/104_Fall03_ppt/Text%20Chapter%2002/OxgnMol.swfhttp://www.usfca.edu/fac-staff/Courses/BIOL104_USF/104_Fall03_ppt/Text%20Chapter%2002/OxgnMol.swfhttp://d/Chapter-2/ppp/Text%20Chapter%2002/OxgnMol.swfhttp://d/Sodium.swf/ -
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Covalent Bonds: Unevenly matched, but
willing to share.
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Thank YouThe End