structure and bonding

Question 1

What does bonding describe

Answer 1

how the outer electrons of atoms interact with each other

Question 2

3 types of bonding

Answer 2

metallic, ionic, covalent

Question 3

what does structure describe

Answer 3

the arrangement of the bonded atoms

Question 4

2 types of structures

Answer 4

giant (lattice) – all metals and ionic, simple – gas or liquid

Question 5

properties of metals x5

Answer 5

strong, high melting point, malleable, ductile, electric conductors

Question 6

meaning of malleable and ductile

Answer 6

malleable – shaped when hit with hammer without breaking, ductile – stretched into wires/cables

Question 7

how are metals held together?

Answer 7

electrostatic attraction between positive ions and delocalised electrons between them

Question 8

what are alloys

Answer 8

mixtures of metals

Question 9

properties of alloys x3

Answer 9

stronger, less malleable and less ductile

Question 10

why are metals conductors of electricity

Answer 10

there are mobile delocalised electrons which carry charge

Question 11

what is combined to form ionic compounds

Answer 11

metal and non-metal ( positive ion to a negative ion)

Question 12

In an ionic compound, the _____ always transfers its outermost shell electrons to the _______

Answer 12

metal, non-metal

Question 13

In ionic bonding, the metal gains/ loses the same number of electrons as its ____ _______

Answer 13

loses, group number

Question 14

3 typical properties of ionic compounds

Answer 14

soluble in water, conducts electricity, high melting point

Question 15

3 typical properties of covalent compounds

Answer 15

low melting point, electric insulator, insoluble in water

Question 16

how are ionic compounds held together?

Answer 16

strong electrostatic forces of attraction between oppositely charged ions

Question 17

why do ionic compounds have high melting points?

Answer 17

a lot of energy is required to overcome strong electrostatic forces of attraction

Question 18

do ionic compounds conduct electricity

Answer 18

yes but only when molten

Question 19

why do ionic compounds conduct electricity when molten/ in solution but not when solid

Answer 19

because ions are fixed in position when solid but are able to move in solution. Electrons can then flow through.

Question 20

structure of ionic compounds

Answer 20

giant lattice

Question 21

covalent bonding occurs between 2 or more ____________

Answer 21

non metals

Question 22

each atom tries to achieve a _____ _______ _____ in covalent bonding

Answer 22

full outer shell

Question 23

electrostatic attraction is between what and what in covalent bonding

Answer 23

positive nuclei and shared pair of electrons

Question 24

attraction forces between molecules are called

Answer 24

intermolecular forces

Question 25

what is the spontaneous movement of a gas to fill its container called

Answer 25

diffusion

Question 26

simple covalent bonds will not conduct electricity because

Answer 26

they don't have delocalized electrons or charged mobile ions

Question 27

the strong covalent bonds do not break when liquid water boils into steam. What is broken then?

Answer 27

intermolecular forces

Question 28

properties of simple covalent molecules x2

Answer 28

low boiling point b.c. of weak intermolecular forces, do not conduct electricity

Question 29

examples of giant covalent structures

Answer 29

diamond, graphite

Question 30

different structural forms of the same element are called

Answer 30

allotropes

Question 31

in fullerenes, each carbon atom is _________ bonded to ______ other carbon stoms

Answer 31

covalently, 3

Question 32

example of fullerene

Answer 32

C60 -- 60 carbon atoms

Question 33

graphene is

Answer 33

a sheet of carbon atoms with no fixed formula

Question 34

graphene is ____ atom thick

Answer 34

1

Question 35

is graphene a good electrical conductor and why

Answer 35

yes, it allows free electrons to move across its surface ( each carbon atoms is only bonded to 3 other carbons )

Question 36

is graphene strong or weak and why

Answer 36

covalent bonds make it extremely strong

Question 37

giant molecular structures of carbon have high/low melting points because ...

Answer 37

high, many strong covalent bonds need to be broken

Question 38

does graphite or diamond conduct electricity

Answer 38

graphite does, diamond doesn't

Question 39

how does graphite conduct electricity

Answer 39

has 3 covalent bonds for each carbon atom --> not all its electrons are held in covalent bonds --> delocalized electrons are free to move and can carry an electrical current

Question 40

uses of graphite x3

Answer 40

pencil, electrodes(conducts electricity but not very reactive), lubricant (layers can slide past each other)

Question 41

what is an ore

Answer 41

a rock containing mental compounds with enough metal in it to make it worth extracting

Question 42

what 3 metals are found pure in the ground (native)

Answer 42

gold, silver, platinum

Question 43

zinc, iron, tin, lead and copper are extracted by...

Answer 43

reduction (smelting)

Question 44

which 5 metals are extracted using electricity? what is the method called

Answer 44

potassium sodium calcium magnesium aluminium, electrolysis

Question 45

what happens in a displacement reaction

Answer 45

a more reactive element takes the place of a less reactive one in a compound

Question 46

is potassium or platinum more reactive

Answer 46

potassium

Question 47

meaning of reduction

Answer 47

loss of oxygen

Question 48

meaning of oxidized

Answer 48

gained oxygen

Question 49

why can only some metals be extracted by reduction?

Answer 49

they have a lower reactivity than carbon, which is used to displace the metal

Question 50

disadvantage of electrolysis

Answer 50

v. expensive as it requires lots of energy

Question 51

meaning of electrolysis

Answer 51

using electricity to split a compound

Question 52

2 methods of extraction for low grade ores

Answer 52

phytoextraction, bioleaching

Question 53

briefly explain phytoextraction

Answer 53

plants absorb metal ions and concentrate these ions in their cells. The plants are burnt leaving plant ash, and the ash is processed using electrolysis or displacement to produce a metal

Question 54

advantages of phytoextraction x2

Answer 54

conserves higher grade ores, reduces habitat destruction

Question 55

disadvantages of phytoextraction x2

Answer 55

long process, costly labour time

Question 56

briefly explain bioleaching

Answer 56

certain bacteria break down low grade ores to produce acidic solution ( leachate), metals can then be extracted by electrolysis or displacement

Question 57

disadvantages of bioleaching

Answer 57

toxic products formed