Bondings

Question 1

When does ionic bonding happen and how ?

Answer 1

With metal + non-metal
When atoms lose or gain electrons

Question 2

What does ionic bonding form

Answer 2

Giant ionic lattice by strong electrostatic forces of attraction

Question 3

What are the properties of ionic bonding

Answer 3

• cannot conduct electricity when solid but when dissolved in water it can
• soluble
• Extremely high melting and boiling points

Question 4

Why can’t ionic compunds conduct electricity when solid

Answer 4

Ions cannot move they are locked together bt strong electostatic forces of attraction

And in water they are free to move

Question 5

Properties of metallic bonding

Answer 5

• Do conduct electricity
• high melting point as electrons are very strong
• insoluble in water
• carry electrical currents and thermal energy
• electrostatic attractions hold everything together
• Sea of delocalised electrons
  *shiny

Question 6

Metallic bonding

Answer 6

The electrons of the outer shell of the metal atom are delocalised (free to move around). There are strong forces of electrostatic attraction between the positive metal ions and the shared negative electrons.

Question 7

Giant covalent

Answer 7

In giant covalent structures, all the atoms are bonded to each other by strong covalent bonds.

Question 8

Properties of giant covalent

Examples

Answer 8

• very high melting and boiling points as lots of energy is needed to break bonds
• don’t conduct electricity apart from graphite or graphene
• Every atom is connected bt strong covalent bonds
• They are always solid at room temperature

Diamond, Graphite and silicon dioxide

Question 9

Simple covalent bonds

Answer 9

They have a small and fixed number of atoms

Question 10

Properties of small covalent bonds

Answer 10

• low melting and boiling points
• usually gases or liquids
• they all boil below room temperature
• does not conduct electricity because the molecules do not have an overall electric charge
• strong covalent bonds but weak intermolecular forces so not engough energy to keep bonds togather when boiling so not much energy is needed for covalent molecules to go from liquid to gas

Question 11

intermolecular

Answer 11

Forces of attraction between molecules

Question 12

Weak intermolecular forces

Answer 12

The weak intermolecular forces between the molecules do not require a lot of energy to break

Question 13

Diamond

Answer 13

diamond is formed from the element carbon
diamonds have high melting points because they have strong covalent bonds so it takes a lot of energy to break them
They can’t conduct electricity as they have 4 bond so no extra electron to carry charges
Rigid lattice structure
can use to strengthen cutting tool

Question 14

How are polymers made

Answer 14

polymers are made by joining together thousands of small identical molecules (monomers)

Question 15

Properties of polymers

Answer 15

most polymers are solid at room temperatures and have a high melting point

Question 16

Forces of attraction between polymers

Answer 16

The intermolecular forces of attraction happen between polymers molecules are relatively strong so it takes a lot of energy to break these forces

Question 17

Metallic bonding

Answer 17

Metalic bonding happens between 2 metals, they have a strong electrostatic forces attraction between the delocalised negative electrons and the positive metal ions
Its structure is a sea of delocalised electrons making a lattice

Question 18

Properties of metals

Answer 18

metals are bent and shaped
in metals the layers of atoms are able to slide over each other

Question 19

What’s an alloy ?

Answer 19

An alloy is a mixture of metals

Question 20

Graphite

Answer 20

1. Each carbon atoms only forms 3 covalent bonds
   there’s no covalent bonds between layers so weak
   2.They are free to move around each other
   high melting point like diamonds
   3.Can conduct electricity as it has one extra electron which is delocalised

Question 21

How are ionic bonds formed ?

Answer 21

When a metal transfers one or more electrons to a non-metal atom to form two oppositely charged ions and then theses two ions will then be attracted to each other by electrostatic forces forming an ionic bond

Question 22

Why do the charges on ions cancel out?

Answer 22

In an ionic compounds, the charges on the ion have to cancel out to leave a overall charge of zero

Question 23

What does ide mean

Answer 23

Ionic compounds that are monotomic ions (by itself) - sulfide s2-

Question 24

What does ate mean

Answer 24

Ionic compounds made from 3 or more different elements end in -ate
They contain more oxygen

Sulfate s04 ( 2-)

Question 25

What does ite mean

Answer 25

mean that it contains oxygen - less oxygen
Sulfite - s03 (2-)

Question 26

What is graphene

Answer 26

A single layer of graphite
It is one atom thick

Question 27

Properties of graphene

Answer 27

An excellent conductor of electricity because it has delocalised electrons

Question 28

What is fullerene

Answer 28

Fullerenes are molecules of cabon atoms with hollow shapes
They usually have a hexagonal rings of carbon atoms but they can also have 5 or 7 rings

Question 29

What can fullerene be used for

Answer 29

Pharmaceutical delivery, lubricants and catalysts

Carbon nanotubes have high tensile strength (can be streched) and good conductors of electricity