Chemical bonding

Question 1

What are the 3 types of bonding for everything in the world

Answer 1

Ionic bonding (metal and non metal )
Covalent bonding ( nonmetals)
Metallic bonding ( silver surfer so think pure metal)

Question 2

Ionic bonding definition

Answer 2

Electrostatic FOA between oppositely charged cations and anions

Explanation (no need) : Ionic bonds are formed when metal atoms transfer their valence electron to non metal atoms. This allow both to achieve stable electronic configuration of completely filled valence shells

THINK DOT AND CROSS DIAGRAM DO YOU KNOW HOW TO DRAW

Question 3

What is the structure of ionic compounds

Answer 3

Giant ionic lattice structure with strong Electrostatic FOA between oppositely charged cations and anions

Question 4

Properties of ionic compounds

Answer 4

High melting and boiling points

Conduct electricity only in molten and aqueous states

Hard and brittle

Soluble in water

Insoluble in organic solvents(methane)

Question 5

Why do ionic compounds have a high m.p. and b.p.

Answer 5

Large amount of heat energy is needed to overcome the strong electrostatic FOA between oppositely charged ions

Question 6

Why do ionic compounds only conduct electricity in aqueous and molten state

Answer 6

To conduct electricity the thing has to have mobile charge carriers

Ionic compounds do not conduct electricity in solid state as in this state the ions are held in fixed positions and so no free-moving ions to conduct electricity

but in aqueous and molten state –> there are free moving ions –> act as mobile charge carriers to conduct electricity

Question 7

Why are ionic compounds hard and brittle

Answer 7

Hard: held tightly in fixed position in the lattice structure by strong electrostatic FOA

Brittle: With sufficient force, layers slide over one another causing ions of the same charge to be brought close together and they repel and the lattice structure breaks apart

Question 8

Covalent bonding definition

Answer 8

A covalent bond is defined as the Electrostatic FOA between positively charged nuclei of atoms and their shared pair of electrons

Explanation: they share lah like two circles combine then got you dot dot in the middle

must know how to draw

Question 9

What structures have covalent bonding

Answer 9

simple covalent/molecular structure

giant covalent structure

Question 10

What bonding is in simple molecular structure

Answer 10

the molecule itself is held by strong covalent bond but why we call this simple is cause between the molecules got this weak as shit force called weak intermolecular forces of attraction(FOA)

since its weak easy to overcome thank goodness cause H2O has this structure which is why its a liquid

Question 11

What are the properties of simple molecular structure

Answer 11

Low melting point and boiling point

Do not conduct electricity

soluble in organic solvents and insoluble in water

Question 12

Why simple molecular structure got low mp and bp

Answer 12

relatively small amount of heat energy is needed to overcome these weak intermolecular FOA between molecules hence most exists as liquid and gases

Question 13

Why do they no conduct electricity

Answer 13

simple they are electrically neutral and the only reason you see in movies that water shock people is cause that water is dirty and not pure so it contains ions which are mobile and so act as mobile charge carriers to conduct electricity

Question 14

What are the 3 giant molecular/covalent structures you need to know everything about

Answer 14

Diamond
Graphite
Silicon dioxide (sand)

Note Diamond and graphite are allotropes of carbon

allotropes are different forms of the same element with different molecular structures

Question 15

What is the structure and bonding of Diamond

Answer 15

Diamond has a giant molecular structure of a tetrahedral network of strong C-C single covalent bonds

Each C atom is bonded to 4 other C atom to achieve a fully stable configuration

Question 16

Physical properties of Diamond

Answer 16

Hard : all atoms are held rigidly in place by strong covalent bonds

Hardest material so can use it for drills and saws

High melting point: Large amount of energy is needed to overcome all the strong C-C covalent bonds

Does not conduct electricity : all the valence electron in the carbon atoms are used for bonding as such there is no free moving electrons that can be delocalised to act as mobile charge carriers to conduct electricity

Question 17

Structure and bonding of Graphite

Answer 17

Graphite consists of flat layers of carbon atoms held together by strong C-C single covalent bonds arranged in hexagonal rings

There are weak intermolecular forces of attraction (van der Waals FOA) btw each layer of carbon atoms

Question 18

Physical properties of Graphite

Answer 18

Slippery: each layer of carbon atoms can slide past one another easily due to weak intermolecular forces of attraction (van der Waals )

So it can act as lubricant

High melting point: Large amount of energy is needed to overcome all the strong C-C covalent bonds

CAN conduct electricity:
Each carbon atom in graphite only uses 3 out of 4 valence electrons for bonding, so 1 electron per carbon atom can be delocalised to act as mobile charge carriers to conduct electricity

Question 19

Silicon dioxide not that impt

Answer 19

Si-O covalent bonds in a 3D tetrahedral arrangement each O atom bonded to 2 Si atoms

Question 20

Silicon dioxide properties

Answer 20

Hard

high mp

does not conduct electricity

ALL THE SAME AS DIAMOND

Question 21

Metals bonding and structure

Answer 21

Metals have a giant metallic structure which is made up of a lattice of metal cations surrounded by a sea of delocalised valence electrons

know how to draw

Question 22

Metallic bonding

Answer 22

electrostatic forces of attraction between cations and the sea of delocalised valence electron

Question 23

Properties of metallic structure

Answer 23

High mp and bp

can conduct electricty and heat

malleable and ductile

Question 24

Why does it have high mp and bp

Answer 24

large amount of thermal energy is needed to overcome the relatively strong electrostatic FOA between the metal cations and sea of delocalised valence electron

Except Group 1 metals and mercury

Question 25

Why can it conduct electricity

Answer 25

metals can conduct electricity in all states , the delocalised valence electrons are able to move freely to act as mobile charge carriers conduct electricity

note the higher the number of delocalised electron (eg group 2 metal each cation contribute 2 electron) the better the conductivity

it can gain heat well cause the delocalised valence electron are MOBILE and help in transfer the heat.

Question 26

why are metals malleable and ductile

Answer 26

malleable means able to be hammered into different shapes without breaking

ductile is can pull into wires

the reason for both these properties is when a force is applied the layers of metal ions are able to slide past each other and take new positions

Question 27

alloy

Answer 27

mixture of metal with other elements( to mess up everything)

Question 28

What are some physical properties of alloys

Answer 28

Varied mp and bp as its a MIXTURE

alloys good conductor of heat and electricity due to mobile ions acting as charge carrier

MOST IMPT : alloys are stronger and harder than pure metals as it contains atoms of different sizes which disrupt the orderly arrangement of atoms in the pure metal

so when a force is applied the layers of atoms cannot slide past each other easily