Molecular Compounds
SNC2D
Molecular Compounds
Sometimes non-metals don’t borrow electrons
from metals to fill their last shell; instead, they
get together and ?
Molecular Compounds
Sometimes non-metals don’t borrow electrons
from metals to fill their last shell; instead, they
get together and share their electrons.
Molecular Compounds
Since they are sharing valence electrons, the bond
formed between the atoms is called ?
Molecular Compounds
Since they are sharing valence electrons, the bond
formed between the atoms is called covalent.
Molecular Compounds
Since they are sharing valence electrons, the bond
formed between the atoms is called covalent.
These compounds can be represented using Lewis
dot diagrams: e.g.
Molecular Compounds
Or, more commonly, by Kekulé diagrams, where
each electron shared is represented by a line
connecting the chemical symbols, e.g.:
Molecular Compounds
Example:
Molecular Compounds
Example:
Multiple Bonds
The sharing of more than one electron is
represented using more than one line, e.g.:
Multiple Bonds
The sharing of more than one electron is
represented using more than one line, e.g.:
There is a double bond between the carbon atoms.
Naming Molecular Compounds
The elements in the name are given prefixes
corresponding to the subscripts (number of
atoms) and the second element is given the
suffix “-ide.”
e.g. CO2 is carbon dioxide
The Prefixes
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1
2
3
4
5
6
7
The Prefixes
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1
2
3
4
5
6
7
Mono-*
The Prefixes
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1
2
3
4
5
6
7
Mono-*
Di-
The Prefixes
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1
2
3
4
5
6
7
Mono-*
DiTri-
The Prefixes
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1
2
3
4
5
6
7
Mono-*
DiTriTetra-
The Prefixes
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1
2
3
4
5
6
7
Mono-*
DiTriTetraPenta-
The Prefixes
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1
2
3
4
5
6
7
Mono-*
DiTriTetraPentaHexa-
The Prefixes
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1
2
3
4
5
6
7
Mono-*
DiTriTetraPentaHexaHepta-
The Prefixes
1
Mono-*
 2
Di 3
Tri 4
Tetra 5
Penta 6
Hexa 7
Hepta* The 1st element in the name never need a mono
Examples
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OF4
N2O
Cl2O7
iodine trichloride
diphosphorus pentoxide
sulphur hexaiodide
Examples
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OF4
N2O
Cl2O7
oxygen tetrafluoride
iodine trichloride
diphosphorus pentoxide
sulphur hexaiodide
Examples
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OF4
N2O
Cl2O7
oxygen tetrafluoride
dinitrogen monoxide
iodine trichloride
diphosphorus pentoxide
sulphur hexaiodide
Examples
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OF4
N2O
Cl2O7
oxygen tetrafluoride
dinitrogen monoxide
dichlorine heptoxide
iodine trichloride
diphosphorus pentoxide
sulphur hexaiodide
Examples
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OF4
N2O
Cl2O7
oxygen tetrafluoride
dinitrogen monoxide
dichlorine heptoxide
iodine trichloride
ICl3
diphosphorus pentoxide
sulphur hexaiodide
Examples
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OF4
N2O
Cl2O7
oxygen tetrafluoride
dinitrogen monoxide
dichlorine heptoxide
iodine trichloride
ICl3
diphosphorus pentoxide P2O5
sulphur hexaiodide
Examples
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OF4
N2O
Cl2O7
oxygen tetrafluoride
dinitrogen monoxide
dichlorine heptoxide
iodine trichloride
ICl3
diphosphorus pentoxide P2O5
sulphur hexaiodide
SI6
Non-Conventional Names
Some compounds are more commonly known by
other names.
e.g. NH3
CH4
H2O
Non-Conventional Names
Some compounds are more commonly known by
other names.
e.g. NH3
CH4
H2O
ammonia
Non-Conventional Names
Some compounds are more commonly known by
other names.
e.g. NH3
CH4
H2O
ammonia
methane
Non-Conventional Names
Some compounds are more commonly known by
other names.
e.g. NH3
CH4
H2O
ammonia
methane
water
The Diatomic Gases
The elemental compounds like H2, Cl2, and O2. are
called diatomic gases and are called simply:
name of element + “gas”
e.g. H2
Cl2
O2
The Diatomic Gases
The elemental compounds like H2, Cl2, and O2. are
called diatomic gases and are called simply:
name of element + “gas”
e.g. H2
Cl2
O2
hydrogen gas
The Diatomic Gases
The elemental compounds like H2, Cl2, and O2. are
called diatomic gases and are called simply:
name of element + “gas”
e.g. H2
Cl2
O2
hydrogen gas
chlorine gas
The Diatomic Gases
The elemental compounds like H2, Cl2, and O2. are
called diatomic gases and are called simply:
name of element + “gas”
e.g. H2
Cl2
O2
hydrogen gas
chlorine gas
oxygen gas
Activity
“Modelling Molecules”
You need a handout and a modelling kit.