unit 1

Question 1

metallic elements within the first 20

Answer 1

Lithium
Beryllium
Sodium
Magnesium
Aluminium
Potassium
Calcium

Question 2

covalent molecular elements within the first 20

Answer 2

H2
N2
O2
F2
Cl2
P4
S8
carbon in form of fullerene (C60)

Question 3

covalent network elements within the first 20

Answer 3

Boron
Silicon
Carbon (diamond and graphite)

Question 4

what is meant by the term covalent radius?

Answer 4

measure of the size of an atom from the nucleus to the outermost electron shell

Question 5

covalent radius going across a period

Answer 5

decreases

nuclear charge increases

therefore, electrons are pulled closer to the nucleus

Question 6

covalent radius going down a group

Answer 6

increases

more electron shells so increased shielding

therefore electrons have a weaker pull towards the nucleus

Question 7

what is meant by the first ionisation energy?

Answer 7

energy required to remove one mole of electrons from one mole of gaseous atoms

Question 8

what is meant by the second ionisation energy?

Answer 8

energy required to remove the 2nd mole of electrons from one mole of gaseous atoms

Question 9

ionisation energy going across a period

Answer 9

increases

nuclear charge increases

pull on outer electrons is stronger so it is harder to remove them

Question 10

ionisation energy going down a group

Answer 10

decreases

more electron shells so increased shielding

therefore electrons have a weaker pull towards the nucleus making it easier to remove them

Question 11

removing electrons from a full outer shell increased ionisation energy

Answer 11

involves the removal of an electron from a full electron shell

this electron shell is also strongly pulled towards the nucleus compared to the previous shell

Question 12

what is meant by the term electronegativity?

Answer 12

the strength an atom has for bonded electrons

Question 13

how to atoms get a delta -/+ charge?

Answer 13

in polar molecules

the atom with the stronger electronegativity pulls the electrons closer given them a delta - charge and the other atom a delta + charge

Question 14

electronegativity going across a period

Answer 14

increases

nuclear charge increases causing the atom to be smaller

stronger attraction on outer electrons

Question 15

electronegativity going down a group

Answer 15

decreases

more electron shells so increased shielding

less attraction on outer electrons

Question 16

why do noble gases not have an electronegativity value?

Answer 16

unreactive/cannot form bonds

Question 17

intramolecular bonding

Answer 17

strong bonds between atoms in the same molecule

Question 18

intermolecular bonds

Answer 18

weak bonds between molecules

Question 19

intermolecular bonds in increasing strength

Answer 19

LDF’s
pd-pd interactions
hydrogen bonding

Question 20

covalent bonding

Answer 20

two positive nuvelei being held together by their common attraction for the shared pair of electrons

Question 21

ionic bonding

Answer 21

electrostatic attraction between positive and negative ions forming a lattice

Question 22

non-polar covalent bonds

Answer 22

forms between atoms with the same electronegativity values

Question 23

polar covalent bonds

Answer 23

atoms have different electronegativity values so there is an uneven sharing of electrons

Question 24

what is a dipole?

Answer 24

uneven distribution of electrons

Question 25

what type of dipole is found in polar molecules?

Answer 25

permanent

Question 26

describe the bonding continuum?

Answer 26

electronegativity difference OR ionic character least - non-polar middle - polar high - ionic

Question 27

how can polar bonds be overall non-polar?

Answer 27

bonds are symmetrically opposed and will cancel out

Question 28

intermolecular forces (van der Waals) in order of increasing strength

Answer 28

LDF's PD-PD interactions H bonding

Question 29

where do LDF's occur?

Answer 29

between all molecules

Question 30

how are LDF's formed?

Answer 30

forces of attraction between temporary dipoles and induced dipoles in nearby molecules

Question 31

how is the strength of an LDF determined?

Answer 31

the more electrons = the stronger it is

Question 32

where do PD-PD interactions occur?

Answer 32

in polar molecules

Question 33

where does hydrogen bonding occur?

Answer 33

in bonds where hydrogen is bonded to either Nitrogen, Oxygen or Fluorine

Question 34

bonding in monatomic

Answer 34

held together by weak LDF's

Question 35

what bonds break in a covalent network?

Answer 35

covalent bonds

Question 36

what bonds are broken in covalent moleculars?

Answer 36

the Van Der Waal force

Question 37

why when comparing MP we need similar GFMs?

Answer 37

similar LDF strength

Question 38

bonds in order of decreasing strength

Answer 38

covalent network ionic metallic polar non-polar monatomic

Question 39

explain the structure of ice

Answer 39

H bonding results in an expanded structure that causes the density of ice to be less than that of water at low temperatures

Question 40

how is viscosity measured?

Answer 40

as the number of H bonds increases, the viscosity increases

Question 41

what is a reducing agent?

Answer 41

substance that donates electrons thing being oxidised

Question 42

what is an oxidising agent?

Answer 42

substance that accepts electrons thing being reduced

Question 43

low electronegativity reducing or oxidising agent?

Answer 43

from ions by losing electrons so act as reducing agents

Question 44

high electronegativity reducing or oxidising agent?

Answer 44

form ions by gaining electrons and act as oxidising agents

Question 45

where can the strongest reducing agents be found?

Answer 45

group 1 top right of the ECS

Question 46

oxidising agent examples

Answer 46

hydrogen peroxide dichromate and permanganate ions in acidic solutions

Question 47

where can the strongest oxidising agents be found?

Answer 47

group 7 bottom left of the ECS

Question 48

reducing agent examples

Answer 48

carbon monoxide

Question 49

oxidising agent uses

Answer 49

kill fungi and bacteria inactivate viruses breaking down coloured compounds - bleach