Chemical Bonding ☹️

Question 1

Which is smaller - mass number or atomic number?

Answer 1

Atomic number

Question 2

Define isotopes

Answer 2

Atoms of the same element with same number of protons but different number of neutrons

Question 3

What properties do isotopes of the same element have

Answer 3

They are the same as they gave the same amount of electrons

Question 4

How do ionic compounds bond

Answer 4

By losing or gaining electrons to make a full shell
( draw the one with square brackets )

Question 5

What ions do metals generally form and what are they called?

Answer 5

+ve ions
Cations

Question 6

What ions do non-metals generally form and what are they called?

Answer 6

-ve ions
Anions

Question 7

How are +ve and -ve ions held together?

Answer 7

Strongly, by electrostatic forces of attraction in a giant lattice

Question 8

Why do ionic substances have high melting and boiling points?

Answer 8

Strong electrostatic forces of attraction between oppositely charged ions throughout giant structure require lots of heat energy to break

Question 9

Why are ionic substances hard but brittle?

Answer 9

Strong forces of electrostatic attraction, but layers can slide, and when ions of same charge align, the structure breaks

Question 10

Why are ionic substances generally soluble in water?

Answer 10

Ions are attracted to polar water molecules, and this attraction breaks the lattice apart

Question 11

Why do ionic substances NOT conduct electricity in solid state?

Answer 11

Charged ions are held in position and are not free to move

Question 12

Why do ionic substances conduct electricity when liquid (or dissolved in solution)

Answer 12

The charged ions are free to move

Question 13

How do covalent compounds bind?

Answer 13

They share a pair of electrons by donating electrons to the shared pair
They then have the same structure as noble gases
Covalent bonds are sometimes also called molecular bonds

Question 14

What are the two types of covalent?

Answer 14

Simple molecular
Giant covalent

Question 15

What are simple molecular?

Answer 15

Made up of tiny molecules which contain multiple atoms held together by covalent bonds

Question 16

What are giant covalent?

Answer 16

They contain millions of atoms bonded together by MANY strong covalent bonds to form a giant molecule, or macromolecule
E.g graphite and diamond

Question 17

Fun fact cos I can’t think of a question for this

Answer 17

Covalent bonds can share two or three electron pairs too

Question 18

Why do simple covalent substances have low melting and boiling points?

Answer 18

Because there are only weak intermolecular forces between molecules, these only need little heat energy to overcome

Question 19

Why do simple covalent substances have poor electrical conductivity?

Answer 19

There are no charged ions or free electrons present

Question 20

Why are simple molecular substances poorly soluble in water?

Answer 20

There are no charged particles present to be attracted to polar water molecules

Question 21

How do you draw a dot and cross diagram for covalent substances

Answer 21

Like a Venn diagram yk

Question 22

Why can giant covalent substances have such different properties?

Answer 22

Because each atom can be bonded to a different amount of other atoms
Diamond - bonded to 4 others
Graphite - bonded to 3 others
But both are carbon

Question 23

What is the structure of diamond?

Answer 23

Each carbon atom covalently bonded to 4 others

Question 24

Why is the melting point of diamond so high?

Answer 24

MANY strong covalent bonds require lots of heat energy to break

Question 25

Why is diamond so hard?

Answer 25

Very hard due to MANY strong covalent bonds

Question 26

Why is diamond a poor electrical conductor?

Answer 26

There are no free electrons, as they are all used in bonding

Question 27

Describe the structure of graphite

Answer 27

Each carbon atom is covalently bonded to 3 others
Graphite has a layered structure with weak intermolecular forces between layers

Question 28

Why does graphite have a high melting point?

Answer 28

Because strong covalent bonds within layers require lots of heat energy to break

Question 29

Why is graphite so soft?

Answer 29

Layers can easily slide over each other due to weak intermolecular forces

Question 30

Why is graphite a good electrical conductor?

Answer 30

There are free electrons between layers (delocalised electrons)

Question 31

What are metallic bonds?

Answer 31

Bonds in metals idfk boo

Question 32

Why do metallic bonds have high melting and boiling points?

Answer 32

Strong attractions between positive metal ion and sea of delocalised electrons

Question 33

Why are metals malleable and ductile?

Answer 33

Layers of metal ions can slide over each other, so structure doesn’t shatter

Question 34

Why are metals good electrical conductors?

Answer 34

Lots of free delocalised electrons that can move around structure

Question 35

Why are metals good conductors of heat?

Answer 35

Delocalised electrons gain kinetic energy, so move faster and transfer energy throughout the metal

Question 36

What is graphene?

Answer 36

A single layer of graphite
Strongest known substance
Could be used for lightweight construction materials

Question 37

First discovered fullerene?

Answer 37

Buckminsterfullerene (C⁶⁰)

Question 38

What are fullerenes?

Answer 38

3D hollow shapes made of carbon
Low mps and bps
Can deliver drugs, act as lubricants and as catalysts

Question 39

What are carbon nanotubes and their uses?

Answer 39

• strong cylindrical fullerenes that are good conductors of heat and electricity
• catalysts often attached to it as they have a large SA

Question 40

What are polymers?

Answer 40

Long chain molecules
Strong intramolecular forces, weak intermolecular forces, but solid at room temp

Question 41

What is polythene?

Answer 41

A type of polymer used for plastic due to its weaker intermolecular forces making it more flexible