Chemistry (Bonding and Reactions)

Question 1

Lewis Structures

Answer 1

Diagrams representing structure of atoms.

1. Count total valence electrons (VE)
2. Fill octets

Question 2

Formal charge

Answer 2

Method to determine whether a compound has a net charge on it and which atom is carrying the charge.

Question 3

Resonance Structures

Answer 3

Multiple possible Lewis Structures

1. Bond connectivity
2. Delocalized electrons
   a. Stabilizes compound to become less reactive.

Question 4

Ionic Bonding

Answer 4

1. Electrons transferred from one atom to another.
2. Electronegativity difference (>1.7)
3. Physical properties:
   a. Very high melting and boiling point.
   b. Liquid state conducts electricity.

Question 5

Covalent Bonding

Answer 5

1. Electrons shared between atoms.
2. Electronegativity difference (<1.7)
3. Physical properties:
   a. Melting + boiling points lower than ionic compounds.

Question 6

Bond order

Answer 6

1. Single, longest, 1 sigma, weakest.
2. Double, medium, 1 sigma + 1 pi, medium.
3. Triple, shortest, 1 sigma + 2 pi, strongest.

Question 7

Polar covalent bond

Answer 7

1. Electrons shared unequally among atoms.
2. Electronegativity difference (0.4 to 1.7)
3. Dipoles
   a. p (dipole moment)= q (charge) * r (charge separation).
4. Physical properties:
   a. Melting + boiling points lower than ionic but greater than non-polar compounds.

Question 8

Non-Polar Covalent bond

Answer 8

1. Electrons shared equally between atoms.
2. Electronegativity difference of elements (< 0.4)
   a. diatomics: N2, O2
   b. alkanes
3. Physical Properties:
   a. Melting + boiling points lower than polar compounds.

Question 9

Coordinate Covalent Bond

Answer 9

1. Electrons shared between atoms.
2. Both electrons donated by one of the atoms.
3. Physical properties:
   a. hybridized characteristics of both ionic and Covalent compounds.

Question 10

London Dispersion Forces

Answer 10

1. Weakest.
2. Induced dipole.
3. Size dependent.
   a. More electrons makes it easier to polarize.

Question 11

Dipole-Dipole

Answer 11

1. Medium.
2. Polar molecules.
3. Strongest in liquid and solid.

Question 12

Hydrogen Bonding

Answer 12

1. Strongest.

2. H bonded to F, O and N.

Question 13

Linear

Answer 13

180°
sp
2 bonds
0 lone pairs
e.g CO2

Question 14

Trigonal Planar

Answer 14

120°
sp2
3 bonds
0 lone pairs
e.g CH2O

Question 15

Bent

Answer 15

104.5 °
sp3
2 bonds
1 or 2 lone pairs
e.g H20

Question 16

Trigonal Pyramidal

Answer 16

107.5 °
sp3
3 bonds
1 lone pair
e.g NH3

Question 17

Tetrahedral

Answer 17

109.5 °
sp3
4 bonds
0 lone pairs
e.g CH4

Question 18

T-shaped

Answer 18

90 ° and 180 °
sp3d 
3 bonds
2 lone pairs
e.g ClF3

Question 19

Seasaw

Answer 19

120 ° and 180 °
sp3d
4 bonds
1 lone pair
e.g SF4

Question 20

Trigonal Bipyramidal

Answer 20

90 ° and 120 °
sp3d
5 bonds
0 lone pairs
e.g PF5

Question 21

Octahedral

Answer 21

90

Question 22

Empirical and Molecular formula

Answer 22

Empirical: simplest whole # ratio of elements in a compound.
Molecular: actual # of atoms in each element in a compound.

Question 23

Equivalents

Answer 23

# of moles of a particular atom in a mole  of a compound
 a. Usually refers to hydrogens in acid e.g HCl has 1 equivalent of Hydrogen

Question 24

Percent composition

Answer 24

By Mass: grams of x/ grams total

By Mole: moles of x/ moles total

Question 25

Percent yield

Answer 25

Actual yield/theoretical yield (0 ≤ % ≤1)

Question 26

Limiting and Excess reactant

Answer 26

Limiting: reactant that is consumed first halting further reaction. Excess: reactant that remains after reaction is terminated.

Question 27

Combination reaction

Answer 27

Add 2 compounds to form new one | S + O2–> SO2

Question 28

Decomposition reaction

Answer 28

One compound breaks into other ones | 2HgO—> 2Hg + O2

Question 29

Single Displacement reaction

Answer 29

Switch metals and salts | Zn + CuSO4 —> Cu + ZnSO4

Question 30

Double Displacement reaction

Answer 30

2 salts exchange ions and cations | CaCl + 2AgNO3 —> Ca(NO3)2 + 2AgCl