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Question 1

What is an ion?

Answer 1

An ion is an electrically charged atom or group of atoms formed by the loss or gain of electrons.

Question 2

Define an ionic bond.

Answer 2

An ionic bond is the strong electrostatic force of attraction between oppositely charged ions.

Question 3

True or False?
Ionic bonds involve the transfer of electrons from a non-metal to a metal.

Answer 3

False.
Ionic bonds involve the transfer of electrons from a metal to a non-metal.

Question 4

How can you use the Periodic Table to determine how many electrons an atom is likely to lose or gain?

Question 5

Give the electronic configuration of a magnesium ion, Mg2+.

Answer 5

The electronic configuration of a magnesium ion is 2.8.

Question 6

Give the electronic configuration of an oxide ion, O2-.

Answer 6

The electronic configuration of an oxide ion is 2.8.

Question 7

What is a binary ionic compound?

Answer 7

A binary ionic compound is composed of ions of two different elements, and consists of a metal cation and a non-metal anion.

Question 8

True or False?
Ionic bonds require little energy to overcome.

Answer 8

False.
Ionic bonds require a lot of energy to overcome.

Question 9

What is the overall charge of an ionic compound?

Answer 9

The overall charge of an ionic compound is 0; they are electrically neutral.

Question 10

What is the formula of the hydrogencarbonate ion?

Answer 10

The formula of the hydrogencarbonate ion is HCO3-.

Question 11

Give the formula of magnesium phosphate.

Answer 11

The formula of magnesium phosphate is Mg3(PO4)2.

Question 12

What is the formula of a phosphate ion?

Answer 12

The formula of the phosphate ion is (PO4)3-.

Question 13

Give the formula of ammonium sulfate.

Answer 13

The formula of ammonium sulfate is (NH4)2SO4.

Question 14

Define lattice dissociation enthalpy (ΔHlattꝋ).

Answer 14

Lattice dissociation enthalpy (ΔHlattꝋ) is the standard enthalpy change that occurs on the formation of 1 mole of gaseous ions from the solid lattice.

Question 15

What forces hold together an ionic lattice?

Answer 15

Strong electrostatic forces of attraction between the oppositely charged ions hold together an ionic lattice.

Question 16

True or False?

The lattice dissociation enthalpy is always an exothermic process.

Answer 16

False.

The lattice dissociation enthalpy is always an endothermic process as energy is always required to overcome the strong electrostatic forces of attraction.

Question 17

True or False?

The lattice dissociation enthalpy is always a positive value.

Answer 17

True.

The lattice dissociation enthalpy is always a positive value because it is always an endothermic process.

Question 18

Define the term volatility.

Answer 18

Volatility refers to the ability of a chemical to vaporise.

Question 19

True or False?

Ionic compounds are volatile.

Answer 19

False.

Ionic compounds are not volatile as large amounts of energy are required to overcome the strong electrostatic forces of attraction between the ions.

Question 20

Why are ionic compounds soluble in water?

Answer 20

Ionic compounds are soluble in water as they can form ion-dipole bonds.

Question 21

Explain the conditions in which an ionic compound can conduct electricity.

Answer 21

Ionic compounds can only conduct when they are molten or in solution as the ions can move and carry a charge.

Question 22

What is a covalent bond?

Answer 22

Covalent bonds are electrostatic attractions between a shared pair of electrons and positively charged nuclei.

Question 23

What is meant by the octet rule?

Answer 23

The octet rule refers to the tendency of atoms to gain a valence shell with a total of 8 electrons.

Question 24

What is expanding the octet rule?

Answer 24

Expanding the octet rule is when the central atom of a covalently bonded molecule can accommodate more than 8 electrons in its outer shell.

Question 25

What is meant by electron deficient?

Answer 25

Electron deficient is when the central atom of a covalently bonded molecule accommodates less than 8 electrons in its outer shell.

Question 26

True or False? Covalent bonds form between non-metal atoms.

Answer 26

True. Covalent bonds form between non-metal atoms.

Question 27

What is a covalent bond?

Answer 27

Covalent bonds are electrostatic attractions between a shared pair of electrons and positively charged nuclei.

Question 28

What is meant by the octet rule?

Answer 28

The octet rule refers to the tendency of atoms to gain a valence shell with a total of 8 electrons.

Question 29

What is expanding the octet rule?

Answer 29

Expanding the octet rule is when the central atom of a covalently bonded molecule can accommodate more than 8 electrons in its outer shell.

Question 30

What is meant by electron deficient?

Answer 30

Electron deficient is when the central atom of a covalently bonded molecule accommodates less than 8 electrons in its outer shell.

Question 31

Why do atoms form covalent bonds?

Answer 31

Atoms form covalent bonds to gain the electronic configuration of a noble gas and become stable.

Question 32

How is a covalent bond represented?

Answer 32

A covalent bond is represented using a straight line, like those shown here in propane.

Question 33

What are meant by electron charge clouds?

Answer 33

Electron 'charge clouds' refer to a region where electrons in a covalent bond are most likely to be found, due to their constant motion.

Question 34

What is the main difference between covalent and ionic bonding?

Answer 34

The main difference is that covalent bonding involves sharing electrons between non-metals, while ionic bonding involves the transfer of electrons between metals and non-metals.

Question 35

What are Lewis formulas?

Answer 35

Lewis formulas show all of the valence electrons, including bonding and non-bonding pairs in a covalently bonded structure.

Question 36

How can electrons be represented in Lewis formulas?

Answer 36

Lewis formulas can be represented using dots, crosses or dashes.