Symbols and Structures of Electrons Flashcards
(29 cards)
Electron-Dot Symbols
Also called a Lewis Symbol, depicts the valence electrons of atoms.
How is the Lewis symbol depicted?
The element is in the center, surrounded by one dot for each of its VALENCE electrons.
Purpose of Lewis Symbols and Structures
A way of depicting valence electrons in an atom.
Valence Electrons = What?
Group Number
How do you fill the spots of valence electrons for an atom?
Fill all the 4 sides up, then pair the atom with another electron.
How to make Lewis Dot symbols for cation?
Remove one dot for each electron lost, include the charge.
How to make Lewis Dot symbol for anion?
Add one dot for each electron gained, surround dots with brackets and include the charge.
What else does the Lewis Structure show? (1)
Show the sharing of electrons in covalent molecules. (Covalent = non-metal + non-metal)
Bonding Pairs
Shared between atoms when two atoms in a Lewis Structure is bonded.
Lone Pairs
Are found on only one atom. But can be found on electrons that are not paired from a compound too.
Octet Rule
Tendency of main group atoms wanting to obtain eight valence electrons (wanting to become like noble gases to become stable).
What number of bonds do non-metals make?
8 minus the group number.
What are double bonds?
Made from 2 shared pairs of electrons (4 total electrons).
Triple Bonds
Made from 3 shared pairs of electrons (6 total electrons).
List bond length shortest to longest of atom
Triple is shortest, double is second shortest, and single is the longest.
List bond strength from strongest to weakest
Triple is strongest, double is second strongest, and single is weakest.
What is rule #1 for Lewis Structure with the octet rule?
The total number of electrons should equal the total number of valence electrons of individual atoms.
What is rule #2 for Lewis Structure with the octet rule?
REMEMBER: Add electrons for anions or subtract electrons for cations.
What is rule #3 for Lewis Structure with the octet rule?
Octet works for all atoms except hydrogen on needs 2 and if the central atom is in period 3 or below, it can have more than 8.
Odd-Electron Molecules
Have an odd number of valence electrons, and therefore have an unpaired electron (Exception to the octet rule).
Electron-Deficient Molecules
Have a central atom that has a few electrons than needed for a noble gas configuration (Exception to the octet rule).
Hypervalent Molecules
Have a central atom that has more electrons than needed for a noble gas configuration.
What to do for Odd-Electron Molecules
If the molecule has a central atom, it will have only 7 electrons instead of 8.
What is the central atom?
The atom with the lowest subscript in the molecular formula and the atom that can form the most bonds.