Ionic bond Polar covalent bond Nonpolar covalent bond Hydrogen bond
IONIC BOND bond formed between a Metal and a Non Metal It is a … · 2018-10-10 · Ionic bond –...
Transcript of IONIC BOND bond formed between a Metal and a Non Metal It is a … · 2018-10-10 · Ionic bond –...
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Challenge 17
Which black rectangle is bigger?
IONIC BOND bond formed between a Metal and a Non Metal It is a transfer of electrons Metals- give up valence electrons Non –metals take in
Ionic Bonding Ionic bonding is the combining of two or more ions to form an
electrically-neutral compound
How Ionic Bonding Works
1) The giving atom loses a valence electron (or 2 or 3) so that
it has a full valence shell, but a positive charge
2) The gaining atom gains a valence electron (or 2 or 3) so
that it has a full valence shell, but a negative charge
3) The negative and positively-charged ions are attracted to
each other (like a magnet) based on their opposite charge
If you look at your periodic table, you will see that ionic
bonding usually occurs in compounds formed between one
metal and one nonmetal
Metals in Ionic Bonds In ionic bonds, metals are always the cation
-- metals are on the left side of the periodic table and only have 1, 2, or 3 valence electrons
-- it is very easy to lose these electrons and become positively charged
Nonmetals in Ionic Bonds Nonmetals (with the exception of hydrogen) are always the anion in ionic bonds
-- nonmetals all have 4 or more valence electrons, so it is very easy for them to gain electrons to get a full valence shell
-- when nonmetals gain electrons, they get a negative charge
Drawing Ionic Bonds When a nonmetal is exposed to a metal, the metal will lose electrons and the nonmetal will gain electrons, forming a new compound
-- that new compound is held together by an ionic bond
The individual atoms will have a charge, but the overall compound will be neutral
When we draw the compound, using Lewis Structures, we show the extra electron around the anion and the cation as having no valence electrons
-- each ion in the compound is shown as being charged
Example:
Na + Cl Na Cl
Ionic compounds result when metals react with nonmetals
Metals lose electrons to match the number of valence
electrons of their nearest noble gas
Positive ions form when the number of electrons are less
than the number of protons
Group 1 metals ion 1+
Group 2 metals ion 2+
Group 13 metals ion 3+
Formation of Ions from Metals
Sodium atom Sodium ion
Na – e Na +
2-8-1 2-8 ( = Ne)
11 p+ 11 p+
11 e- 10 e-
0 1+
Formation of Sodium Ion
Magnesium atom Magnesium ion
Mg – 2e Mg2+
2-8-2 2-8 (=Ne)
12 p+ 12 p+
12 e- 10 e-
0 2+
Formation of Magnesium Ion
Group 1 Group 2 Group 13
H+ Mg2+ Al3+
Li+ Ca2+
Na+ Sr2+
K+ Ba2+
Some Typical Ions with Positive Charges (Cations)
A. Number of valence electrons in aluminum
1) 1 e- 2) 2 e- 3) 3 e-
B. Change in electrons for octet
1) lose 3e- 2) gain 3 e- 3) gain 5 e-
C. Ionic charge of aluminum
1) 3- 2) 5- 3) 3+
Learning Check
A. Number of valence electrons in aluminum
3) 3 e-
B. Change in electrons for octet
1) lose 3e-
C. Ionic charge of aluminum
3) 3+
Solution
Give the ionic charge for each of the following:
A. 12 p+ and 10 e- 1) 0 2) 2+ 3) 2-
B. 50p+ and 46 e-
1) 2+ 2) 4+ 3) 4-
C. 15 p+ and 18e-
2) 3+ 2) 3- 3) 5-
Learning Check
unpaired electron octet 1 -
: F + e : F :
2-7 2-8 (= Ne) 9 p+ 9 p+ 9 e- 10 e- 0 1 - ionic charge
Fluoride Ion
In ionic compounds, nonmetals in 15, 16, and
17 gain electrons from metals
Nonmetal add electrons to achieve the octet
arrangement
Nonmetal ionic charge:
3-, 2-, or 1-
Ions from Nonmetal Ions
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
Ionic Bond
Diagram of Ionic Bonding
1). Ionic bond – electron from Na is transferred to Cl,
this causes a charge imbalance in each atom. The Na
becomes (Na+) and the Cl becomes (Cl-), charged
particles or ions.
• In an IONIC bond, electrons are given or
taken, resulting in the formation of IONS.
• The “bond” holds the atoms together and
is a result of the negative and positive ions
attracting to one another (opposites attract).
F K
What happens in an ionic bond?
F K
F K
F K
F K
F K
F K +
_
•The compound potassium fluoride
consists of a potassium (K+) ion
and a fluoride (F-) ion.
•K is positive now because it gave an
electron and F is more negative because
it took the electron.