Unit 6 Test pt.2

Question 1

why does covalent bonding happen? why do things bond at a particular bond length?

Answer 1

Covalent bonding occurs when atoms share electrons to achieve a more stable electron configuration. when most things bond, they can minimize their potential energy, and they minimize it the MOST if the nuclei are a specific distance away from each other.

Question 2

What is ionic bonding?How is it different from covalent bonding?

Answer 2

Ionic bonding is the chemical bonding that results from the electrical attraction between large number of cations and anions. Electronegativity difference (Metal with non-metal is ionic, and non-metal with non-metal is covalent).

Question 3

How do Ionic compounds minimize their potential energy? How does ionic bonding explain the properties of ionic compounds? Why are ionic compounds brittle?

Answer 3

Ionic compounds minimize their potential energy by creating crystal lattice structures.

Ionic bonds are usually so strong that they have high melting points and high boiling points

Ionic compounds are brittle because when a external force is applied it can break or mess up the crystal lattice structure

Question 4

How are the properties of ionic and covalent compounds different? why do they have these differences?

Answer 4

Ionic compounds are harder but tend to be brittle. Ionic compounds have higher melting and boiling points. covalent compounds do not conduct electricity, even when dissolved. Ionic compounds will conduct electricity if dissolved in distilled water. This is because the force of attraction between covalent bonds are much less.

Question 5

Metallic bonding– how the bond type explains the properties of metals?

Answer 5

Metallic bonds have highly mobile valence electrons, many electrons are packed together in a small space and the outer electrons are not held very tightly. This results in dense, strong materials.

Question 6

Intermolecular forces—describe each type and rank them in order of strength.

Answer 6

1. hydrogen bonding: the intermolecular force in which a hrdrogen atom that is bonded to a highly EN atom is attracted to the lone pair of an atom in a nearby molecule.
2. Dipple-Dopple forces: the attraction between polar molecules.
3. London Dispersion forces: the Intermolecular attractions resulting from the constant motion of electrll..ons and the creation of instantaneous dipoles.

Question 7

How do IM forces explain differing properties of covalent compounds?

Answer 7

IM forces dictate how strongly molecules attract each other, which directly affects physical properties.