Chemical Bonding

Question 1

What are the three ways atoms can chemically bond?

Answer 1

• Ionic bonding
• Metallic bonding
• Covalent bonding

Question 2

What is ionic bonding?

Answer 2

Ionic bonding involves an attraction between oppositely charged ions. Ionic bonds are found in compounds made of metals and non-metals.

Question 3

What is covalent bonding?

Answer 3

Covalent bonding involves 2 atoms sharing one or more pairs of electrons. Covalent bonds are found in most non-metals elements and in non-metal compounds.

Question 4

What is metallic bonding?

Answer 4

Metallic binding involves am attraction between positively charged ions and negatively charged delocalised electrons. Metallic bonds are found in metald and alloys.

Question 5

What are ions?

Answer 5

Ions are particles that have a charge, they are created when an atom or molecule gains or loses electrons.

Question 6

What are cations and how are they formed?

Answer 6

Cations are positive ions usually created when an atom/molecule loses electrons. They are most likely to be group 1 and 2 metals.

Question 7

What are anions and how are they formed?

Answer 7

Anions are negative ions that are usually created when at atom/molecules gains electrons. Non-metals in group 7 are most likely to become negatively charged.

Question 8

How are ionic lattices formed?

Answer 8

Ionic compounds form giant structures called ionic lattices that are held together by strong electrostatic forces of attraction between positive and negative ions.

Question 9

What are the different types of covalent bonding?

Answer 9

• Single covalent bond
• Double covalent bond
• Triple covalent bond

Question 10

What are the differences of single covalent bonds compared to double and triple covalent bonds?

Answer 10

Triple covalent bonds are stronger and require more energy to break

Question 11

What are the 3 different states of matter?

Answer 11

Solid, liquid, gas

Question 12

What are the properties of a solid?

Answer 12

• Particles are very close together and vibrate in a fixed position.
• When heated, the particles vibrate more intensely
• Solids have a fixed shape and volume

Question 13

What are the properties of a liquid?

Answer 13

• Particles are very close together but can move and flow past each other.
• Liquids have a fixed volume but can change shape.
• When heated, the average speed of particles increase.

Question 14

What are the properties of a gas?

Answer 14

• Particles are far apart and move randomly in all directions.
• Gases can change shape and volume.
• When heated, the average speed of particles increase.

Question 15

What are the different processes of a substance changing state?

Answer 15

Melting - Solid to liquid
Boiling - Liquid to gas
Freezing - Liquid to solid
Condensing - Gas to liquid
Sublimation - Solid to gas
Deposition - Gas to Solid

Question 16

What is aqueous?

Answer 16

Aqueous are substances dissolved in water.

Question 17

What are the properties of ionic compounds?

Answer 17

• High melting/boiling points
• Don’t conduct electricity if solid

Question 18

What are intermolecular forces?

Answer 18

Intermolecular forces are forces between different molecules.

Question 19

Why do covalent molecules have low melting and boiling points?

Answer 19

Covalent molecules have weak intermolecular forces which are easy to break.

Question 20

What are intramolecular forces?

Answer 20

The strong covalent bonds found within small molecules.

Question 21

What does the size of a molecule affect overall?

Answer 21

The overall strength of intermolecular forces.

Question 22

What is graphite?

Answer 22

Graphite is a giant covalent structure that has a higher melting point that methane.

Question 23

Why does graphite have a higher boiling point than methane?

Answer 23

It requires you to break covalent bonds, rather than weak intermolecular forces.

Question 24

What are polymers?

Answer 24

Polymers are large, chain-like molecules that can extend for thousands of atoms.

Question 25

How are polymers held together?

Answer 25

- Strong covalent bonds between atoms in molecules. - Weak intermolecular forces between molecules.

Question 26

What does the 'n' tell us in a repeat unit of poly(propene)?

Answer 26

How many times the unit is repeated to give the polymer.

Question 27

What are some properties of giant covalent structures?

Answer 27

- No specific formula - Very high melting points - 1 Large molecule

Question 28

What are pure metals?

Answer 28

Pure metals have giant structures with strong electrostatic forces between positive ions and delocalised electrons.

Question 29

What are the properties of pure metal?

Answer 29

- Soft / malleable - High melting / boiling points

Question 30

What is the structure of a diamond?

Answer 30

A diamond is a giant covalent structure, a small diamond can contain 50,000 carbon atoms, where a larger diamond could contain 1,000,000,000 carbon atoms.

Question 31

What is an alloy?

Answer 31

An alloy is a combination of 2+ elements where at least one is metal.

Question 32

What are the properties of alloys?

Answer 32

- Mixture of 2+ elements - Layers are distorted - Harder than pure metals

Question 33

What are allotropes?

Answer 33

Allotropes are different forms of the same element e.g. diamond, graphite.

Question 34

What are the properties of diamond?

Answer 34

- Diamond does not conduct electricity. - Every carbon atom in diamond is bonded to 4 other carbon atoms by strong covalent bonds. - Diamond is hard - Diamond has a high melting point.

Question 35

What are the properties of graphite?

Answer 35

- Every carbon atom is graphite is bonded to 3 other carbon atoms by strong covalent bonds. - Graphite is soft. - Graphite conducts electricity.

Question 36

What are the properties of graphene?

Answer 36

- Graphene conducts electricity - Graphenes are light but strong - Graphenes are 1 atom thick

Question 37

What are fullerenes?

Answer 37

Fullerenes are molecules of carbon atoms that take up hollow structures. Their structure is usually carbon atoms arranged in hexagonal rings (pentagonal and heptagonal carbon rings can be found).

Question 38

What was the first fullerene to be discovered?

Answer 38

Buckminsterfullerene

Question 39

What are the common uses for spherical fullerenes?

Answer 39

- Catalysts - Lubricants - As vehicles for transporting drugs into our bodies

Question 40

What are carbon nanotubes?

Answer 40

Carbon nanotubes are fullerenes that take the shape of a cylinder, often called molecular wires because they have a tiny diameter but incredibly long.

Question 41

How strong are cylindrical fullerenes?

Answer 41

Because of the strong covalent bonds between carbon atoms, nanotubes are exceptionally strong for their size.

Question 42

What are the common uses for cylindrical fullerenes?

Answer 42

- In electronics - In nanotechnology - For strengthening materials

Question 43

What is the formula for buckminsterfullerene?

Answer 43

C60

Question 44

How big is a nanoparticle?

Answer 44

1 - 100 nm long 10 - 1000 atoms

Question 45

How big are fine particles?

Answer 45

100 - 2500 nm long 1000 - 25000 atoms

Question 46

How big are coarse particles (dust)?

Answer 46

2,500 - 10,000 nm long 25,000 - 100,000 atoms

Question 47

What are nanoparticles?

Answer 47

Nanoparticles are tint particles between 1 - 100 nm in length. They are larger than individual atoms but too small to be seen with the human eye.

Question 48

How does the use of nanoparticles compare to that of larger particles?

Answer 48

- Less expensive - More efficient

Question 49

How would you describe the surface area to volume ratio of nanoparticles?

Answer 49

Extremely high

Question 50

What are the main uses of nanoparticles?

Answer 50

- Catalysts - Cosmetics - Medicine - Electronics - Deodorants