Bohr And Lewis Diagram /ionic Compounds/multivalent Elements Flashcards
What is a Bohr Diagram?
A Bohr Diagram shows how many electrons an atom/element has in each energy level/shell.
How many electrons can each shell hold?
1st shell can hold 2
2nd shell…can hold 8
3rd shell …can hold 8
Valence Shell
The outermost shell that contains electrons
Stable Octet
A full outer shell of 8 electrons
Valence Electrons
An electron in the valence shell
(These are e- involved in chemical bonding)
Lewis Diagrams
An easier method of showing chemical bonding
What does a Lewis Diagram show?
How many valence electron an atom has and how they’ve been grouped
Grouping electrons
Once there are more than 4 e-, they start to “buddy up”.
Things to notice:
I am an atom with 1 valence electron. Can you tell what group I’m in?
Group 1
Alkali Metals
Think, Pair, Share: I am an atom with 2 electron shells. Can you tell what period I’m in?
Yes,
Period 2
Forming compounds:
What happens when atoms move close together?
Their valence electrons interact
Atoms want to become stable by having a full valence shell. How does that happen?
Atoms will often try to gain or lose electrons to achieve this -turning them into IONS.
What is an ION?
An atom with a net electric charge.
A cation has a positive charge
An anion has a negative charge
What are the two main types of chemical bonding?
- Ionic Bonding - electrons are transferred between atoms.
Example: Na + Cl = NaCl - Covalent Bonding - electrons are shared between atoms.
Atoms vs molecules vs Compounds
Atoms are…
Atoms are the smallest possible pieces of an element
Example: an atom of calcium (Ca)
Atoms vs Molecules vs Compounds
Molecules are…
Groups of 2 or more atoms stuck together.
Atoms vs Molecules vs Compounds
Compounds are…
Compounds are materials composed of groups of different atoms.
Some molecules are compounds
What is an Ion charge?
Ion charge : the charge an atom will have once it becomes an ion.
Naming Ionic Compunds
What is the rule for naming ionic compunds?
(Cation ) + (anion with “ide” suffix)
What are Multivalent Elements?
More than one Ion charge.
Examples: manganese
Uranium
If one element can form more than one type of ion, how are we to know which one to choose?
We use Roman numerals
What are Polyatomic Ions?
- Charged molecule. In other words, they’re ions made up of more then 1 atom
- They cannot exist on their own
