Atoms and Ionic Bonding

Question 1

What are compounds?

Answer 1

Atoms of two or more elements chemically combined together.

Question 2

What is an isotope?

Answer 2

A different atomic form of the same element with the same number of protons but a different number of neutrons.

Question 3

What are two isotopes of carbon?

Answer 3

Carbon-12 and carbon-14.

Question 4

What is ionic bonding?

Answer 4

Atoms gain or lose electrons to form charged particles (ions) which are strongly attracted to each other.

Question 5

Why are ions strongly attracted to each other?

Answer 5

Opposite charges.

Question 6

What kind of ions do metals usually form?

Answer 6

Positively charged ions.

Question 7

What structure do ionic compounds usually form?

Answer 7

Giant ionic lattices.

Question 8

How are giant ionic lattices held together?

Answer 8

Very strong electrostatic forces of attraction between oppositely charged ions, in all directions.

Question 9

Why do ionic compounds have high melting and boiling points?

Answer 9

It takes a lot of energy to overcome the strong attraction between the ions.

Question 10

Under what conditions do ionic compounds conduct electricity?

Answer 10

Molten or dissolved in water.

Question 11

Why do ionic compounds only conduct electricity when molten or dissolved in water?

Answer 11

The ions can move separately, so they can carry a current.

Question 12

What is a covalent bond?

Answer 12

Shared pair of electrons.

Question 13

What are the two structures that can be formed from covalent bonds?

Answer 13

Simple molecules and giant covalent.

Question 14

Why are melting and boiling points of simple molecules low?

Answer 14

The intermolecular forces are weak.

Question 15

Why don’t molecular substances conduct electricity?

Answer 15

There are no ions, so there is no electric charge.

Question 16

What are giant covalent structures also known as?

Answer 16

Macromolecules.

Question 17

Why do giant covalent structures have high melting and boiling points?

Answer 17

Strong covalent bonds between all the atoms.

Question 18

Give three examples of giant covalent structures.

Answer 18

1. Diamond
2. Graphite
3. Sand

Question 19

Why are diamonds hard?

Answer 19

Each carbon atom forms four covalent bonds in a very rigid structure.

Question 20

Why is graphite soft?

Answer 20

Each carbon atom only forms three covalent bonds, so the layers are able to slide over each other.

Question 21

Why can graphite be used in pencils?

Answer 21

The intermolecular forces between layers are weak.

Question 22

Why is graphite a good conductor of heat and electricity?

Answer 22

Each carbon atom has a free electron that conducts heat and electricity.

Question 23

What is the scientific name for sand?

Answer 23

Silicon dioxide or silica.

Question 24

What kind of structure do metals form?

Answer 24

Metallic structures.

Question 25

Where do the free electrons in metals come from?

Answer 25

The outer shell of every metal atom in the structure.

Question 26

What is the force holding metallic structures together?

Answer 26

Electrostatic attraction.

Question 27

Why can metals be bent and shaped?

Answer 27

The layers of atoms slide over each other.

Question 28

What is an alloy?

Answer 28

A mixture of metals.

Question 29

Why are alloys harder than pure metals?

Answer 29

Other metals distort the layers of atoms, so they can’t slide over each other.