Chapter 1: Introduction and Review

Question 1

What term is used to describe different substances with the same molecular formula but different structures?

Answer 1

Constitutional isomers also known as structural isomers

Question 2

According to the ________ theory of matter, each element will generally form a particular number of bonds

Answer 2

Structural

Question 3

I when two atoms share electrons it is defined as a ______ bond.

Answer 3

Covalent

Question 4

When two hydrogen atoms approach each other, several forces must be taken into account…

Answer 4

1. The force of repulsion between two electrons
2. The force of repulsion between two positively charged nuclei
3. The forces of attraction between two positively charged nuclei and the negatively charged electrons

Question 5

How are bond energy and stability related?

Answer 5

…

Question 6

________ provide a method for keeping track of electrons, but they may or may not correspond to real charges.
Thus an atom may bear a partial charge.

Answer 6

Formal charge

Question 7

How is formal charge calculated?

Answer 7

(Valence electrons on free atom) - (non-bonding electrons) - (1/2 shared electrons)

Question 8

What is the trends for electronegativity?

Answer 8

Increasing electronegativity going to the right and up on the periodic table

Ionic compounds have a large difference in electronegativity

Question 9

Electron density is best represented by…

Answer 9

Density mapping

Question 10

Electron density that is zero is called…

Answer 10

Node

Question 11

In filling atomic orbitals, three simple principles are applied:

Aufbau principal….

Answer 11

Building up principal

Question 12

In filling atomic orbitals, three simple principles are applied:

Pauli principle…

Answer 12

No two electrons can have the same four quantum numbers

Question 13

In filling atomic orbitals, three simple principles are applied:

Hund’s rule…

Answer 13

Electrons always enter an empty orbital before they pair up.

Question 14

Hybridization rule number one:

Both sigma bonding electrons and _________ occupy hybrid orbitals.

Answer 14

Lone pairs

Question 15

Hybridization rule number two:

Answer 15

…

Question 16

Hybridization rule number three:

If two or three pairs of electrons form a multiple bond between two atoms, the first bond is a sigma bond formed by a hybrid orbital. The second bond is a ______, consisting of two lobes above and below the Sigma bond formed by two P orbitals.
The third bond of a triple bond is another pi bond perpendicular to the first pi bond.

Answer 16

Pi bond

Question 17

What is the steric number?

Answer 17

How many groups are around the central atom

Question 18

The melting points, boiling points, and solubilities of organic compounds is effected by

Answer 18

Dipole moments and polarity

Question 19

Attractive intermolecular forces resulting from the attraction of the positive and negative ends of the dipole moments of polar molecules

Answer 19

Dipole- dipole forces

Question 20

In nonpolar molecules, The principal attractive force is the _________.
They arise from temporary dipole moments that are induced in a molecule by other nearby molecules

Answer 20

London dispersion forces

Question 21

_________ is not a true bond but particularly strong form of dipole-dipole attraction. (not as strong as covalent)

Answer 21

Hydrogen bond

Includes hydrogen bonding to oxygen, nitrogen or fluorine. (Bonded to O or N)

Question 22

List the polar and nonpolar bonds

Answer 22

Polar: hydrogen and dipole-dipole
Nonpolar: London forces

Question 23

Hydrogen bonding has a large effect on _________ properties of organic compounds.
Example…

Answer 23

Physical

Ex: boiling point (much higher)

Question 24

________ form stronger hydrogen bonds than _______.

Answer 24

Alcohols, amines

Probably because the O-H Bond is more strongly polarized than the N-H bond.

Question 25

What is the bond angle for tetrahedral, trigonal planer, linear

Answer 25

109.5- tetrahedral 120- trigonal planner 180- linear