Chemical Bonding

Question 1

Explain why does ionic compounds have a high melting point and boiling point.

Answer 1

A large amount of energy is needed to overcome the strong forces of attraction between the ions.

Question 2

Explain why does covalent compounds have a low melting and boiling point.

Answer 2

Little energy is needed to overcome the weak intermolecular forces.

Question 3

Explain why does ionic compound only conduct electricity in molten or aqueous state.

Answer 3

In molten or aqueous state, ions are free to move about to act as mobile charge carriers to conduct electricity.

Question 4

ionic compound or covalent compound?

non-metal + metal

Answer 4

ionic compound

Question 5

ionic compound or covalent compound?

metal + metal

Answer 5

covalent compound

Question 6

how does a chlorine atom become a chloride ion?

Answer 6

1. State how many valence electrons are there
   A chlorine atom has 7 valence electrons
2. No. of electrons to gain/lose to have a full/stable valence electron shell?
   Gains 1 electrons to obtain a stable electronic configuration of 2.8.8

Question 7

how does a magnesium atom become a magnesium ion?

Answer 7

A magnesium atom has 2 valence electrons, loses 2 electrons to obtain a stable electronic configuration of 2.8

Question 8

Define Isotopes

Answer 8

Isotopes are atoms of the same element with the same number of protons and electrons, but different number of neutrons

Question 9

State the charge of the particles of an atom, (proton, neutron & electrons)

Answer 9

proton +1
neutron 0
electron -1

Question 10

State the relative mass of the particles of an atom, (proton, neutron & electrons)

Answer 10

proton 1
neutron 1
electrons 1/1840

Question 11

Why cant ionic compounds conduct electricity in solid state?

Answer 11

For a substance to be conductive it must contain particles that are charged and free to move
So ionic compounds cannot conduct electricity when are solid but can conduct electricity when they are aqueous or molten.
In solid state the ions are held in place, thus there are no free moving ions to conduct electricity,

Question 12

what is a cation

Answer 12

Anion- negAtively charged ions
CATION positively charged ions, the ions lose electrons to attain a full valence electron shell, a positive ion is formed. (mostly metal atoms)
For example; sodium NA+, magnesium Mg2+, hydrogen H+

Question 13

what is an anion?

Answer 13

negatively charged ions, the ions gain electrons to attain a full valence electron shell, a negative ion is formed. (mostly NON- metal atoms)
For example; bromide Br-, chloride Cl-, Carbonate CO3²-

Question 14

what is an ion?

Answer 14

a charge particle formed by the losing/gaining/sharing of outer electrons

Question 15

name a few polyatomic ions

Answer 15

Ammonium, NH4+
Hydroxide, OH- 
Nitrate, NO3-
Carbonate, CO32-
Sulfate, SO42-

Question 16

what is an ionic compound

Answer 16

transferring of electrons

Question 17

what is a covalent compound?

Answer 17

sharing of electrons

Question 18

what does H - H mean

Answer 18

it means that in the covalent bond, there are 2 electrons being shared!

Question 19

what does O = O mean

Answer 19

it means that in the covalent bond there are 2 pairs, 4 electrons being shared!