Symbols and Structures of Electrons

Question 1

Electron-Dot Symbols

Answer 1

Also called a Lewis Symbol, depicts the valence electrons of atoms.

Question 2

How is the Lewis symbol depicted?

Answer 2

The element is in the center, surrounded by one dot for each of its VALENCE electrons.

Question 3

Purpose of Lewis Symbols and Structures

Answer 3

A way of depicting valence electrons in an atom.

Question 4

Valence Electrons = What?

Answer 4

Group Number

Question 5

How do you fill the spots of valence electrons for an atom?

Answer 5

Fill all the 4 sides up, then pair the atom with another electron.

Question 6

How to make Lewis Dot symbols for cation?

Answer 6

Remove one dot for each electron lost, include the charge.

Question 7

How to make Lewis Dot symbol for anion?

Answer 7

Add one dot for each electron gained, surround dots with brackets and include the charge.

Question 8

What else does the Lewis Structure show? (1)

Answer 8

Show the sharing of electrons in covalent molecules. (Covalent = non-metal + non-metal)

Question 9

Bonding Pairs

Answer 9

Shared between atoms when two atoms in a Lewis Structure is bonded.

Question 10

Lone Pairs

Answer 10

Are found on only one atom. But can be found on electrons that are not paired from a compound too.

Question 11

Octet Rule

Answer 11

Tendency of main group atoms wanting to obtain eight valence electrons (wanting to become like noble gases to become stable).

Question 12

What number of bonds do non-metals make?

Answer 12

8 minus the group number.

Question 13

What are double bonds?

Answer 13

Made from 2 shared pairs of electrons (4 total electrons).

Question 14

Triple Bonds

Answer 14

Made from 3 shared pairs of electrons (6 total electrons).

Question 14

List bond length shortest to longest of atom

Answer 14

Triple is shortest, double is second shortest, and single is the longest.

Question 15

List bond strength from strongest to weakest

Answer 15

Triple is strongest, double is second strongest, and single is weakest.

Question 16

What is rule #1 for Lewis Structure with the octet rule?

Answer 16

The total number of electrons should equal the total number of valence electrons of individual atoms.

Question 17

What is rule #2 for Lewis Structure with the octet rule?

Answer 17

REMEMBER: Add electrons for anions or subtract electrons for cations.

Question 18

What is rule #3 for Lewis Structure with the octet rule?

Answer 18

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.

Question 19

Odd-Electron Molecules

Answer 19

Have an odd number of valence electrons, and therefore have an unpaired electron (Exception to the octet rule).

Question 20

Electron-Deficient Molecules

Answer 20

Have a central atom that has a few electrons than needed for a noble gas configuration (Exception to the octet rule).

Question 21

Hypervalent Molecules

Answer 21

Have a central atom that has more electrons than needed for a noble gas configuration.

Question 22

What to do for Odd-Electron Molecules

Answer 22

If the molecule has a central atom, it will have only 7 electrons instead of 8.

Question 23

What is the central atom?

Answer 23

The atom with the lowest subscript in the molecular formula and the atom that can form the most bonds.

Question 24

What is an Electron-Deficient Molecule/Compound

Answer 24

A central atom’s octet is incomplete due to lack of electrons.

Question 25

What do electron-deficient molecules tend to react to?

Answer 25

Other molecules that contain lone pairs and form a coordinate covalent bond.

Question 26

What is a Coordinate Covalent Bond?

Answer 26

Both electrons in the bond come from only one atom.

Question 27

Hypervalent Molecule

Answer 27

When atoms contain more than eight electrons in their valence shell. It has access to d orbitals and can have more than 8 electrons.

Question 28

Hypervalent molecules can have what?

Answer 28

Lone pairs on the central atom.