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Week6Presentation.pptxCHEMICAL
BONDING
Occurs in two different ways:
1)
2)
Ionic bonds
Covalent bonds
IONIC BONDING
- an ionic bond involves the transfer of electrons from one atom to another
- what happens when you take electrons away from one atom and give them to another???
- it leaves you with 2 oppositely charged ions
- what happens when you have two opposites???
- they attract each other
- this attraction “bonds” the two atoms together
Na + Cl Na + Cl
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Na + Cl Na+ + Cl-
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Opposites...
NaCl
- the charges will always equal out to be zero
Cl Cl
Mg + Mg +
Cl Cl
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Mg + 2Cl Mg+2 + 2Cl-
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Opposites...
MgCl2
Remember….the charges will always equal out to be zero
Naming Inorganic Compounds
- Ionic Compounds
- Give the name of the cation first, followed by the stem of the anion plus the suffix –ide. Do not give the number of atoms in an ionic compound’s name.
NaCl
Sodium & Chlor +ide => Sodium Chloride
Mg(No3)2
-Magnesium & Nitrate => Magnesium Nitrate
COVALENT BONDING
- covalent bonds involve the sharing of electrons between combining atoms
Cl + Cl Cl Cl
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- notice that each now has eight electrons in its outermost shell
- making it stable
- when two electrons or one pair of electrons is being shared it is known as a
- single covalent bond
- can be written
Cl—Cl
- gives us the formula
Cl2
- Oxygen exists in nature with a covalent bond also
O + O O O
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- note again that each atom now has eight electrons in its outermost shell
- when four electrons or two pair of electrons are being shared it is known as a
- double covalent bond
- can be written
- gives us the formula
O2
O=O
- Nitrogen also exists in nature with a covalent bond
N + N N N
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- again…..each atom has eight electrons in its outermost shell
- when six electrons or three pair of electrons are being shared it is known as a
- triple covalent bond
- can be written
N N
- gives us the formula
N2
Naming Inorganic Compounds
- Covalent Compounds
- Generally, name the elements in the order they appear giving the number of atoms for each element as a prefix to its name. The last element’s name is abbreviated using the stem followed by the suffix –ide.
CO2
-2 Hydrogen & 1 Oxygen => Dihydrogen Monoxide
H2O
-1 Carbon & 2 Oxygen => Carbon Dioxide
Hg + S HgS
or
=
The above is called a
chemical equation
- it is a combination of chemical symbols and formulas used as a shorthand way to represent the reactants and products in a chemical change
The is used instead of an equal sign
- to indicate the direction of the reaction
Hg + S HgS
vs
Hg + S HgS
- The is read as “yields” or “produces”
- the substance or substances behind the arrow of the equation are
- the reactants
- they are what are going through the reaction or “reacting”
- the reactants will “yield or produce”
- the products
- found in front of the arrow
- above the arrow can be written a catalyst for the reaction
- a catalyst is a substance or substances added to a reaction to alter it’s rate
- or change the speed of the reaction
- a catalyst is never “used” in the reaction
- it will come into the reaction and “cause” things to happen and then still be left in tact after the reaction is complete
CO2 + H2O chlorophyll C6H12O6
