AP Chemistry Unit 2

The process of bonding redistributes (blank)

valence electrons so each atom in a bond can have eight assigned to it.

The octet rule

bonds can have 8 assigned to it

Atoms redistribute valence electrons by (blank)

transferring them fully to other atoms, or by sharing with other atoms

The energy required to pull them apart and break the resulting bond is called (blank)

Bond energy

Metals lose electrons to become (blank)

cations

Nonmetal gain electrons to become (blank)

anions

The electrostatic attractions ions experience is an (blank)

ionic bond

Ionics which are also called salts, are made of these ions arranged in a (blank)

Lattice structure

Melting or boiling salts requires (blank)

breaking the ions out of the lattice so they are free to move around as a liquid or gas

Salts tend to have tremendously (blank)

high melting and boiling points

the bond energy required to break ions out is called (blank)

Lattice energy

The strength of the ionic bond is directly proportional to the (blank)

Magnitude of charge on the ions and inversely proportional to the distance between them

• Ex: NaF has a +1 charge and MgO2 has +2, therefore MgO2 would have the higher melting and boiling point

• Can’t use charge to rank ALL of the ions

Metal bonds are generally stationary but their valence electrons don’t belong to a specific atom, this is called

Sea of electrons

“Fluid” electrons explain why (blank)

metals are such good conductors of electricity and heat and why metals are malleable. Also why they do not mix well with other phases

• Ex: not soluble in water

Metals can bond with each other to form (blank)

alloys

Interstitial Alloy and Substitutional alloy

interstitial Alloy are metal atoms with two vastly different radii combine

Substitutional alloy forms between atoms of similar radii

In a covalent bond, two atoms share (blank)

electrons

The law of definite proportions states (blank)

that molecules of a certain compound are made of a characteristic number of different types of atoms

The first covalent bond formed between two atoms is called (blank)

a sigma bond

Additional bonds (double/triple) between the two atoms are formed are called (blank)

pi bonds

This (blank) corresponds to the distance where the atoms are most stable with the lowest potential energy

internuclear distance

The depth of the well below zero potential energy is the (blank)

Bond Strength

What do the 3 areas in this graph mean?

1. The point at 0 means they’re not interacting

2. further left and below zero, this favorable interactions gets them to a more stable state with lower potential energy than not interacting at

3. The highest point means that the nuclei repel each other as they get too close together

In a (blank) atoms are held together in a lattice of covalent bonds.

Network Solid

Network Solids are (blank)

very hard, have very high melting and boiling points, and are insoluble in water.

Network Solids contain (blank)

Carbon or Silicon because they have four valence electrons, which means they can form many covalent bonds

Electricity is conducted through the (blank)

Ions and Electrons

Solid Ionic substances are not conductors of electricity because (blank)

The ions trapped in the lattice structure on to their electrons and are immobile

If a salt is dissolved in water or melted, the (blank)

Lattice breaks down and the mobile ions formed can conduct electricity.

Solid and liquid metals conduct electricity because (blank)

of their highly mobile sea of valence electrons

Why don’t Covalent substances conduct electricity?

Their valence electrons are immobilized between the atoms and there are no ions to speak of.

Is pure water a good conductor?

No because most water that humans use is not very pure.

How well an aqueous solution conducts electricity depends on the (blank)

total concentration of dissolved ions.

How to draw a lewis dot structure

1. Count the total number of valence electrons, (for anions or cations make sure to either add or subtract)

2. Draw atomic symbols and draw lines connecting them

3. Calculate the number of electrons assigned to each atom

4. add and assign lone pairs until the peripheral atoms have 8 bonded and lone to fulfill the octet rule

5. Add remaining to the central atom

6. If the central tom has fewer than 8 than remove a pair from an outer atom to add another bond

How to find the average bond order?

The sum divided by the number of resonance structures.

• Ex: 1+2+/3 (the top is the bonds, single bond, double bond

Some resonance forms are better than others, you can select which ones based on (blank)

Formal Charge

Formal charge is calculated by

1. subtracting the electrons assigned to an atom in molecule step from the number of valence electrons in the unbound atom.

Rules of Formal Charge

• Negative chargers are more stable when they are on the electronegative atom

• and the opposite for positive chargers

Incomplete Octets and Expanded Octets

• Incomplete Octets means that some atoms are stable with less than eight atoms (Hydrogen, Helium, Beryllium and boron)

• Expanded Octets Certain atoms are large enough to accommodate more than eight electrons but never more than 12 (Phosphorus, sulfur, chlorine, larger noble gases can also do this.

Name the shape, angle and amount of lone pairs and domains

1. Linear

2. 180

3. 0

4. 2

Name the shape, angle, amount of lone pairs and domains

1. Trigonal Planar

2. 120

3. 0

4. 3

Name the shape, angle, amount of lone pairs and domains

1. Bent

2. 120

3. 1

4. 3

Name the shape, angle, amount of lone pairs and domains

1. Tetrahedral

2. 109.5

3. 0

4. 4

Name the shape, angle, amount of lone pairs and domains

1. Trigonal Pyramidal

2. 109.5

3. 1

4. 4

Name the shape, angle, amount of lone pairs and domains

1. Bent

2. 109.5

3. 2

4. 4

Name the shape, angle, amount of lone pairs and domains

1. Trigonal bipyramidal

2. 120 and 90

3. 0

4. 5

Name the shape, angle, amount of lone pairs and domains

1. seesaw

2. 120 and 90

3. 1

4. 5

Name the shape, angle, amount of lone pairs and domains

1. T-shaped

2. 120 and 90

3. 2

4. 5

Name the shape, angle, amount of lone pairs and domains

1. Linear

2. 120 and 90

3. 3

4. 5

Name the shape, angle, amount of lone pairs and domains

1. Octahedral

2. 90

3. 0

4. 6

Name the shape, angle, amount of lone pairs and domains

1. Square Pyramidal

2. 90

3. 1

4. 6

Name the shape, angle, amount of lone pairs and domains

1. Square Planar

2. 90

3. 2

4. 6