Definitions

Question 1

Define a compound.

Answer 1

A compound is a substance that is made up of two or more different elements combined together chemically

Question 2

Define the Octet Rule.

Answer 2

When bonding occurs, atoms tend to reach an electron arrangement with eight electrons in the outermost energy level

Question 3

Define an ion.

Answer 3

An ion is a charged atom or group of atoms

Question 4

Define an ionic bond

2

Answer 4

An ionic bond is the force of attraction between oppositely charged ions in a compound

Ionic bonds are always formed by the complete transfer of electrons from one atom to another

Question 5

Define a transition metal

Answer 5

A transition metal is one that forms at least one ion with a partially filled d sublevel

Question 6

Define a molecule.

2

Answer 6

A molecule is a group of atoms joined together

It is the smallest particle of an element or compound that can exist independently

Question 7

Define the valency of an element.

Answer 7

The valency of an element is defined as the number of atoms of hydrogen or any other monovalent element with which each atom of the element combines

Question 8

Define a sigma bond

Answer 8

A sigma bond is formed by the head-on overlap of two orbitals

Question 9

Define a pi bond.

Answer 9

A pi bond is formed by the sideways overlap of p orbitals

Question 10

Define electronegativity

Answer 10

Electronegativity is the relative attraction that an atom in a molecule has for the shared pair of electrons in a covalent bond

Question 11

Define a polar covalent bond.

2

Answer 11

A polar covalent bond is a bond in which there is unequal sharing of the pair (or pairs) of electrons

This causes one end of the bond to be slightly positive (delta +) and the other end slightly negative (delta -)

Question 12

Define intramolecular bonding.

2

Answer 12

Intramolecular bonding is bonding that takes place within a molecule, i.e. it holds the atoms together

Covalent bonding and polar covalent bonding are examples of intramolecular bonding

Question 13

Define intermolecular forces.

2

Answer 13

Intermolecular forces are the forces of attraction that exist between molecules

Van der Waals forces, dipole-dipole forces and hydrogen bonding are examples of intermolecular forces

Question 14

Define Van der Waals forces

2

Answer 14

Van der Waals forces are weak attractive forces between molecules resulting from the formation of temporary dipoles

They are the only forces of attraction between non-polar molecules

Question 15

Define dipole-dipole forces.

Answer 15

Dipole-dipole forces are forces of attraction between the negative pole of one polar molecule and the positive pole of another polar molecule

Question 16

Define hydrogen bonds

3

Answer 16

Hydrogen bonds are particular types of dipole-dipole attractions between molecules in which hydrogen atoms are bonded to nitrogen, oxygen or fluorine

The hydrogen atom carries a partial positive charge and is attracted to the electronegative atom in another molecule

Thus, the hydrogen bond acts as a bridge between two electronegative atoms in separate molecules