Bonding Rules, Lewis Structures, and Metallic Properties

Question 1

Why do atoms form bonds?

Answer 1

Because bonding lowers the potential energy of species and stabilizes them.

Question 2

How do you write the Lewis dot symbol for a main group element?

Answer 2

• Write the element’s symbol
• Place as many dots around it as there are valence electrons
• Place one dot on each of the four sides before adding a second dot.

Question 3

What does the octet rule say?

Answer 3

Atoms will gain, lose, or share electrons to have a filled outer level with eight valence electrons (or two for Li and H)

Question 4

Across a period, is bonding more covalent, ionic, or metallic?

Answer 4

Across a period, bonding becomes more covalent.

Question 5

Down a group, is bonding more covalent, ionic, or metallic?

Answer 5

Down a group, bonding is more metallic.

Question 6

Does Be form covalent or ionic bonds with halogens?

Answer 6

Covalent.
This is an exception to the general rule that metals and nonmetals form ionic bonds. It is due to the small size and high ionization energy of Be.

Question 7

For a metal element, what does the number of dots in its Lewis structure indicate?

Answer 7

The number of electrons that an atom loses to form a cation.

Question 8

For a nonmetal, what does the number of unpaired dots in its Lewis structure indicate?

Answer 8

How many electrons an atom gains to form an anion or the number of electrons it shares in a covalent bond.

Question 9

The most metallic elements have larger or smaller:
- Ionization energy
- Atomic radius
- Number of outer electrons
- Effective nuclear charge

Answer 9

More metallic elements have
- Lower ionization energy
- Larger atomic radii
- Fewer outer electrons
- Lower effective nuclear charge

Question 10

Where on the periodic table are the most metallic elements?

Answer 10

Lower left