Ionic Bonding

Question 1

What is an ion?

Answer 1

An ion is an atom or group of atoms that has gained or lost electrons and has a charge.

Question 2

How do metals form ions, and which type of ion is formed?

Answer 2

Metals lose electrons to form positively charged ions called cations.

Question 3

How do non-metals form ions?

Answer 3

Non-metals gain electrons to form negatively charged ions called anions.

Question 4

Why do atoms form ions?

Answer 4

Atoms form ions by transferring electrons to achieve a full outer shell, which makes them more stable.

Question 5

How does a sodium atom form an ion?

Answer 5

Sodium has 1 electron in its outer shell, so it loses 1 electron to achieve a full outer shell and becomes a Na⁺ ion.

Question 6

How does an oxygen atom form an ion?

Answer 6

Oxygen has 6 electrons in its outer shell, so it gains 2 electrons to achieve a full outer shell and becomes an O²⁻ ion.

Question 7

How can you predict the type of ion an element will form?

Answer 7

By looking at its group in the periodic table: Group 1 → lose 1 electron → +1, Group 2 → lose 2 electrons → +2, Group 6 → gain 2 electrons → -2, Group 7 → gain 1 electron → -1

Question 8

What is ionic bonding, and what attracts the two ions?

Answer 8

Ionic bonding occurs when a metal reacts with a non-metal and electrons are transferred from the metal to the non-metal.

The resulting oppositely charged ions are held together by electrostatic attraction.

Question 9

How do dot and cross diagrams work?

Answer 9

They represent electrons as dots or crosses to show electron arrangements in atoms or ions, and indicate which atom each electron originally came from.

Question 10

Example of lithium fluoride (LiF) formation?

Answer 10

Lithium (1 outer electron) loses 1 electron → Li⁺. Fluorine (7 outer electrons) gains 1 electron → F⁻. Electrostatic attraction forms LiF.

Question 11

Example of lithium oxide (Li₂O) formation?

Answer 11

Lithium (1 outer electron) loses 1 electron → Li⁺. Oxygen (6 outer electrons) gains 2 electrons → O²⁻. Two lithium ions combine with one oxygen ion → Li₂O.

Question 12

What charge does a group 1 element form when it becomes an ion?

Answer 12

+1

Question 13

What charge does a group 2 element form when it becomes an ion?

Answer 13

+2

Question 14

What charge does a group 6 element form when it becomes an ion?

Answer 14

-2

Question 15

What charge does a group 7 element form when it becomes an ion?

Answer 15

-1

Question 16

What is a cation, and when is one formed?

Answer 16

A positively charged ion, formed when a metal loses electrons.

Question 17

What is an anion, and when is one formed?

Answer 17

A negatively charged ion, formed when a non-metal gains electrons.

Question 18

How do ions achieve stability?

Answer 18

By having the same electronic structure as a noble gas (full outer shell).

Question 19

How many electrons does a group 1 atom lose to form an ion?

Answer 19

1 electron

Question 20

How many electrons does a group 2 atom lose to form an ion?

Answer 20

2 electrons

Question 21

How many electrons does a group 6 atom gain to form an ion?

Answer 21

2 electrons

Question 22

How many electrons does a group 7 atom gain to form an ion?

Answer 22

1 electron

Question 23

What holds positive and negative ions together in an ionic compound?

Answer 23

Electrostatic forces of attraction (ionic bonds).

Question 24

Dot and cross diagrams cannot show what?

Answer 24

The size of ions, the arrangement of ions in the solid lattice, or the three-dimensional structure of the compound.

Question 25

What is the general formula for predicting ion charges?

Answer 25

Metals (Groups 1–3): charge = group number. Non-metals (Groups 6–7): charge = 8 − group number.

Question 26

Sodium ion (Na⁺) electronic structure?

Answer 26

Sodium (Na) has 11 electrons → loses 1 → 10 electrons → 2,8

Question 27

Magnesium ion (Mg²⁺) electronic structure?

Answer 27

Magnesium (Mg) has 12 electrons → loses 2 → 10 electrons → 2,8

Question 28

Chloride ion (Cl⁻) electronic structure?

Answer 28

Chlorine (Cl) has 17 electrons → gains 1 → 18 electrons → 2,8,8

Question 29

Oxide ion (O²⁻) electronic structure?

Answer 29

Oxygen (O) has 8 electrons → gains 2 → 10 electrons → 2,8

Question 30

Why do elements in the same group form ions with the same charge?

Answer 30

They have the same number of outer electrons, so they lose or gain the same number to achieve a full outer shell.