AOS 2-How can the versatility of non-metals be explained?

Question 1

what is a molecule?

Answer 1

it is a group of two or more atoms covalently bonded

Question 2

how does something conduct electricity?

Answer 2

for something to conduct electricity, there must be free moving delocalised electrons

Question 3

what does it mean if something is unable to conduct electricity?

Answer 3

if something is unable to conduct electricity, this means that there are no free moving electrons

Question 4

what does it mean if something is able to conduct electricity?

Answer 4

if something is able to conduct electricity, this means that there are freely moving charged particles

Question 5

what is an elements melting point?

Answer 5

an elements melting point is the amount of energy needed to break the intermolecular bonds

Question 6

what is an elements boiling point?

Answer 6

an elements boiling point if the amount of energy needed to further break intermolecular bonds as well as the intramolecular bonds

Question 7

what is intramolecular bond?

Answer 7

this bond is the bond present between atoms of a molecule

Question 8

what is intermolecular bond?

Answer 8

this bond is the bond present between molecules

Question 9

what does a high melting point indicate?

Answer 9

high melting point indicates strong intermolecular forces

Question 10

what does a low melting point indicate?

Answer 10

low melting point indicates weak intermolecular forces

Question 11

give 2 examples of non-metal elements(you can refer to a periodic table)

Answer 11

fluorine and chlorine

Question 12

explain why non-metals do not conduct electricity

Answer 12

non-metals do not give away their electrons, so they do not have free flowing charged particles

Question 13

explain why non-metals have low melting and boiling points

Answer 13

the bonds between these molecules are weak and so not much energy is required to break these bonds

Question 14

what are the two most important types of bonds relating to molecular compounds

Answer 14

intermolecular and intramolecular

Question 15

compare and contrast intermolecular and intramolecular bonds

Answer 15

-intramolecular bonds are much stronger than intermolecular bonds

Question 16

what is covalent bonding?

Answer 16

covalent bonding is a type of bonding between non-metals. electrons are shared

Question 17

where does covalent bonding occur?

Answer 17

it occurs between non-metals

Question 18

how does covalent bonding happen?

Answer 18

it happens when two or more non-metals need electrons to fulfil their outer shells

Question 19

how does covalent bonding differ to ionic bonding?

Answer 19

in covalent bonding, electrons are shared instead of being transferred like in ionic bonding

Question 20

what is the octet rule?

Answer 20

it is a rule where an atoms valence shell must contain 8 electrons to be stable

Question 21

what is a lone pair?

Answer 21

a lone pair is a pair of two electrons of an atom being bonded, but these electrons aren’t part of a bond

Question 22

how can bonds between atoms be shown in a visual manner?

Answer 22

they can be shown in diagrams such as the lewis dot diagram/electron dot diagram and valence structure

Question 23

what is electron dot structure?

Answer 23

electron dot structure is when the number of valence electrons are drawn around the elements symbol

Question 24

what is valence structure?

Answer 24

it is when lines are drawn between chemical symbols to show each bond. one line will show 2 bonding electrons, 2 lines will show 4 bonding electrons. there is a maximum of 3 lines

Question 25

in what atom/element might single bonds occur?

Answer 25

hydrogen

Question 26

in what atom/element might double bonds occur?

Answer 26

oxygen

Question 27

in what atom/element might triple bonds occur?

Answer 27

nitrogen

Question 28

when are molecules most stable?

Answer 28

molecules are most stable when atoms have a full outer shell

Question 29

what does VSEPR stand for?

Answer 29

valence shell electron pair repulsion

Question 30

explain VSEPR theory

Answer 30

this theory models the idea that electron pairs in a valence shell will have a charge that will repel the other electron.

Question 31

what are the 4 shapes of molecules?

Answer 31

- linear - angular/bent v shape - pyramidal - tetrahedral

Question 32

what are the three types of intermolecular forces?

Answer 32

dipole-dipole force, hydrogen bonding, dispersion force

Question 33

how can the three types of intermolecular forces be explained?

Answer 33

the three types of intermolecular forces can be explained through electronegativity and polarity

Question 34

what is electronegativity? what is the trend of this in the periodic table?

Answer 34

electronegativity is the tendency of an atom to attract electrons. this will increase up and left to right on the periodic table

Question 35

what is polarity?

Answer 35

the tendency of a molecule to have an electric dipole

Question 36

what is an electric dipole?

Answer 36

it is a slightly positive charge at one end of a molecule and a slightly negative charge on the other end.

Question 37

what is a diatomic molecule?

Answer 37

it is a molecule made up of two atoms only, these atoms can be the same or different elements

Question 38

what is a non-polar diatomic molecule? give an example

Answer 38

oxygen gas, O2

Question 39

what is a polar diatomic molecule? give example

Answer 39

hydrogen fluorine, HF

Question 40

what is dipole-dipole force?

Answer 40

a force that only occurs in polar molecules.

Question 41

what is hydrogen bonding?

Answer 41

it is a special type of dipole dipole bond. it is when a hydrogen is bonded to a nitrogen, oxygen or fluorine atom

Question 42

what are dispersion forces?

Answer 42

this force is present between all molecules. they result from random movement of electrons forming temporary dipoles

Question 43

when do the three types of intermolecular forces occur?

Answer 43

dipole-dipole: occurs in polar molecules hydrogen: occurs when a hydrogen atom is bonded to either fluorine, oxygen or nitrogen dispersion: a force that is present in all molecules

Question 44

order the three forces from strongest to weakest

Answer 44

hydrogen bonding, dipole-dipole, dispersion

Question 45

why is carbon so important?

Answer 45

carbon is vital for life and the economy.

Question 46

what are the isotopes of carbon?

Answer 46

carbon-12, carbon-13, carbon-14

Question 47

is the melting point of carbon low or high?

Answer 47

the melting point of carbon is high

Question 48

what sort of state change does carbon undergo?

Answer 48

carbon undergoes sublimation, where it changes state between solid and gas. it skips liquid

Question 49

can carbon conduct electricity? explain

Answer 49

despite carbon being a non-metal, some structures/arrangements of carbon can allow it to conduct electricity.

Question 50

what is an allotrope?

Answer 50

allotropes are different structural arrangements of the same element

Question 51

what are the three allotropes of carbon?

Answer 51

diamond, graphite, amorphous carbon

Question 52

describe properties of diamond

Answer 52

very hard because it has a 3D covalent lattice structure and each carbon is bonded to another carbon. diamond cannot conduct electricity

Question 53

describe properties of amorphous carbon

Answer 53

carbon atoms are randomly arranged. it is a fine black powder which can conduct electricity.

Question 54

describe properties of graphite

Answer 54

it is soft, its structure is a 2D layer lattice. conducts electricity because each carbon is bonded rot three other carbons and so there is one free moving electron.

Question 55

why can carbon form so many compounds?

Answer 55

carbon always wants 4 bonds so this is why Caron can form many compounds

Question 56

what are fullerenes?

Answer 56

they are spherical structures, with carbon atoms forming 3 bonds with delocalised electrons

Question 57

how many bonds do carbon in fullerenes have?

Answer 57

3 bonds

Question 58

what is the structure of fullerenes?

Answer 58

fullerenes are like a sphere.

Question 59

what is graphene?

Answer 59

graphene is a single layer of graphite. it is 2D and each carbon is bonded to 3 other carbons

Question 60

what are carbon nanotubes?

Answer 60

it is a layer of graphene rolled into a tube or cylinder