C3 - Bonding

Question 1

An ionic bond occurs between what atoms?

Answer 1

A metal and a non-metal atom

Question 2

A covalent bond occurs between what atoms?

Answer 2

2 non-metal atoms

Question 3

A metallic bond occurs between what atoms?

Answer 3

2 metal atoms

Question 4

In ionic bonds what are the 2 atoms attracted by?

Answer 4

Electrostatic force

Question 5

Ionic compounds exist in what structure and why?

Answer 5

Lattices
It forms because each ion is electrostatically attracted in all directions to ions of the opposite charge.

Question 6

In covalent bonds what are the 2 atoms attracted by?

Answer 6

Electrostatic force

Question 7

What is a dative/co-ordinate bond?

Answer 7

A dative covalent bond is a covalent bond in which a shared pair of electrons has been supplied by one of the bonding atoms only.

Question 8

How is a dative bond shown in a dot and cross diagram?

Answer 8

By → or ← with the arrow coming from the atom that provided the electrons

Question 9

In metallic bonds what are the 2 atoms attracted by?

Answer 9

Electrostatic force between the metal ions and the electrons

Question 10

How does metal ion size affect the strength of metallic bonds?

Answer 10

The smaller the metal ion, the closer the positive nucleus is to the delocalized electrons. This means there is a greater attraction between the two, which creates a stronger metallic bond.

Question 11

Do ionic structures conduct electricty?

Answer 11

They conduct electricity when molten or dissolved in water as the ions are free to move

Question 12

Do metallic structures conduct electricty?

Answer 12

They conduct electricity when solid or molten due to movement of delocalised electrons

Question 13

Do marcomolecular structures conduct electricty?

Answer 13

They do not apart from graphite in a solid

Question 14

Do molecular structures conduct electricty?

Answer 14

Does not conduct electricty as there are no charged particles

Question 15

What is the boiling and melting point of ionic structures?

Answer 15

High as breaking strong ionic bonds requires lots of energy

Question 16

What is the boiling and melting point of metallic structures?

Answer 16

High as breaking electrostatic forces of attraction requires lots of energy

Question 17

What is the boiling and melting point of macromolecular structures?

Answer 17

Very high as they have many strong covalent bonds

Question 18

What are the properties of ionic structures?

Answer 18

Hard due to strong electrostatic forces of attraction that hold ions together

Question 19

What is the boiling and melting point of molecular structures?

Answer 19

Low as they are small structures with weak bonds

Question 20

What is a molecular structure?

Answer 20

Simple covalent

Question 21

What are the properties of metallic structures?

Answer 21

Malleable and Ductile as layers slide over each other

Question 22

What are the properties of macromolecular structures?

Answer 22

Varies depending on the structure
E.g. rigid and hard for diamond but brittle for graphite

Question 23

What are the properties of molecular structures?

Answer 23

Brittle as they don’t have strong bonds holding them together

Question 24

What is macromolecular structure?

Answer 24

Giant covalent structure

Question 25

What is a bonding pair?

Answer 25

A pair of electrons in a covalent bond

Question 26

What is a lone pair?

Answer 26

Pairs of electrons that are not involved in bonding

Question 27

What is bond length?

Answer 27

The distance between the nuclei of two bonded atoms

Question 28

What is bond angle?

Answer 28

Angle between two covalent bonds

Question 29

What is a linear shaped molecule?

Answer 29

2 bonding pairs around the central atom, with the 2 pairs at an angle of 180* As well as 2 bonding pairs and 3 lone pairs

Question 30

What is a traigonal planar shaped molecule?

Answer 30

3 bonding pairs around the central atom, with all 3 bonds on the same plane and a bond angle of 120*

Question 31

What is a tetrahedral shaped molecule?

Answer 31

4 bonding pairs around the central atom, with a bond angle of 109.5*

Question 32

What is a trigonal bipyramid shaped molecule?

Answer 32

5 bonding pairs around the central atom, 3 pairs in 1 plane have a bonding angle of 120*, the 2 other pairs are 90* to this plane. (triagonal planar with one above and one below)

Question 33

What is a octahedral shaped molecule?

Answer 33

6 bonding pairs around the central atom, bond angle of 90* between all the bonds.

Question 34

How is the number of lone pairs calculated?

Answer 34

Total number of electron pairs - number of bonding pairs

Question 35

What is a pyramidal shaped molecule?

Answer 35

3 bonding pairs, 1 lone pair, bond angle of 107*

Question 36

What is a bent shaped molecule?

Answer 36

2 bonding pairs, 2 lone pairs, bond angle of 104.5*

Question 37

What is a T-shaped molecule?

Answer 37

3 bonding pairs, 2 lone pairs, bond angle of 86*

Question 38

What is a square planar shaped molecule?

Answer 38

4 bonding pairs, 2 lone pairs, bond angle of 90*

Question 39

What is electronegativity?

Answer 39

The ability of an atom to attract a bonded pair of electrons in a covalent bond

Question 40

If one atom is more electronegative than another in a covalent bond which atom are the electrons closer to?

Answer 40

The more electronegative atom

Question 41

What direction does electronegativity increase in the periodic table?

Answer 41

Increases going from bottom left to top right, with fluorine being the most electronegative Increases across a period, Decreases down a group

Question 42

What 3 factors is electronegativity dependent on?

Answer 42

Atomic number Atomic radius (shielding)

Question 43

If an atom has its electrons closer to itself than the other atom (is more electronegative) what is its charge?

Answer 43

δ- (delta negative) This means it has a slight negative charge

Question 44

If an atom is has its electrons further away and closer to the other atom (is less electronegative) what is its charge?

Answer 44

δ+ (delta positive This means it has a slight positive charge

Question 45

What happens if the electronegativity of both atoms in a covalent bond is identical?

Answer 45

The electrons in the bond will be equally attracted to both of them. This results in a symmetrical distribution of electron density around the two atoms. So a non-polar bond is formed

Question 46

What happens if the electronegativity of atoms in a covalent bond are different?

Answer 46

An asymmetrical distribution of electron density is created as one attracts electrons more strongly.

Question 47

What is an imbalance in the charges in the bond called?

Answer 47

A dipole

Question 48

If the electronegativity difference is 0 what is the bond type?

Answer 48

Covalent bond

Question 49

If the electronegativity difference is between 0 and 1.8 what is the bond type?

Answer 49

Polar covalent with more ionic character the higher the difference

Question 50

If the electronegativity difference is 1.8 or higher what is the bond type?

Answer 50

Ionic bond

Question 51

How are the bonds arranged in a non-polar molecule?

Answer 51

The polar bonds are symmetrical and the partial charges will cancel out

Question 52

How are the bonds arranged in a polar molecule?

Answer 52

The polar bonds are asymmetrical and the partial charges will not cancel out

Question 53

What are the 3 types of bonding between dipoles?

Answer 53

Van der Vaal forces Permanent dipole dipole forces Hydrogen bonds

Question 54

What are Van der Vaals forces

Answer 54

Forces of attraction due to induced dipole–dipole forces caused by movement of electrons in atoms and molecule

Question 55

How can a Van der Vaal force be stronger?

Answer 55

By being a bigger molecule with more electrons

Question 56

What are permanent dipole dipole forces?

Answer 56

Intermolecular force between 2 polar molecules and their δ+ and δ- charges

Question 57

How can permanent dipole dipole forces be stronger?

Answer 57

A higher electronegativity difference which makes the charges more positive or negative

Question 58

What is a hydrogen bond?

Answer 58

The attraction between a lone pair of electrons on one electronegative atom and an H atom bonded to either N, O of F