Metals

Question 1

Main group metals

Answer 1

metals in s and p block

Question 2

transition metals

Answer 2

in d block

generally have unfilled d sub shell

Question 3

Ores

Answer 3

Metals combined with non metals

Question 4

Mineral

Answer 4

Naturally occurring solid substance with a definite chemical composition, structure and properties.

Question 5

Metals bonding and ions

Answer 5

Metals are larger than non metals in the same period because of their lower core charge
Ionisation energy of metals is lower than that of non metals
Therefore metals can achieve greater stability by releasing one or more of their valence electrons into a common pool of electrons within the lattice

Question 6

structure of metals

Answer 6

regular 3d lattice of cations
ions occupy fixed positions in a closely packed lattice
delocalised electrons which come from the valence shell are free to move throughout the lattice
localised electrons, electrons in the inner shells, are not free to move

Question 7

How are ions held in metallic lattice

Answer 7

Ions are held by their attraction to delocalised electrons which extends throughout the lattice and is called metallic bonding.

Question 8

Reason for metal structure

Answer 8

Solid where there is a lattice of metal cations and sea of delocalised electrons must be more stable than solid made up of seperate metal atoms

Question 9

Properties of metals

Answer 9

good conductors of electricity and heat
lustrous 
malleable and ductile
high melting and boiling temp
generally dense

Question 10

Metals are good conductors of electricity

Answer 10

delocalised electrons are free to move

Question 11

Metals are good conductors of heat

Answer 11

delocalised electrons bump into each other and ions and transfer energy
When metal is heated, particles get more energy and vibrate more rapidly
delocalised electrons transmit this energy rapidly throughout the lattice

Question 12

Metals are lustrous

Answer 12

Delocalised electrons reflect light and appear shiny

Question 13

Metals are malleable and ductile

Answer 13

When beaten into sheets or drawn into wires, layers of the positive ions are forced across each other
delocalised electrons move so that they still surround positive ions
electrostatic forces may change but still operate
prevent the ions from aligning and repelling when an external force is applied

Question 14

Metals tend to have high melting and boiling temperatures

Answer 14

Attraction forces between the positive ions and delocalised electrons in the metal lattice are very strong

Question 15

Metals are generally dense

Answer 15

Ions in a metal lattice are closely packed

Density depends on the mass of the ions, their radius and the way in which they are packed in the lattice

Question 16

Transition metal properties

Answer 16

Compared to main group metals:
harded
higher densities
higher melting points
(atoms of transition metals are smaller because of higher core charge which allows them to pack together more tightly with stronger bonds)
Compounds (oxides, chlorides etc) display colours
Strong magnetic properties

Question 17

Transition metal compounds display colours

Answer 17

Electrons absorb light of particular wavelength and move to higher energy levels.
Absorbance of light with some wavelengths and transmission of light of other wavelengths results in the compound appearing coloured

Question 18

Reactivity of metals

Answer 18

Most reactive metals have lowest IE

Reactivity of metal and Ionisation energy are inversely proportional

Question 19

Metals tend to be more reactive with

Answer 19

acids than water

Question 20

Transition metal reactivity

Answer 20

usually less reactive than the main group metals

Question 21

Metal + h2o->

Answer 21

metal OH- + H2 (g)

Question 22

Metal + oxygen (o2) ->

Answer 22

metal oxide (s)

Question 23

2K(s) + 2HCl (aq) ->

Answer 23

2KCl (aq) +H2 (g)

Question 24

Alloys

Answer 24

Metals (usually Fe because of high abundance) are mixed with small amounts of another substance, usually a metal or carbon
The substances are melted, mixed and then allowed to cool
alloy has no chemical formula because it is not a substance and not chemically combined

Question 25

Alloy properties compared to pure metals

Answer 25

harder, less malleable and lower melting point

poor electrical conductors

Question 26

Alloys harder, less malleable and lower melting point

Answer 26

atoms of different size dont pack in same way as the main metal and do not allow lattice to shift or bend. disruption of the regular metallic lattice also accounts for these properties

Question 27

Alloys poor electrical conductors

Answer 27

Delocalised electrons have restricted movement due to the close packing of different sized particles in the lattice

Question 28

Substitutional alloy

Answer 28

made of elements that have similar chemical properties and atoms of similar size to main metal (must be another metallic cation)
all metal cations are attracted to sea of delocalised electrons so lattice is strongly bonded

Question 29

Interstitial cation

Answer 29

small proportion of an element with atoms of small atomic radius are added to a metal (usually a non-metal like carbon)

Question 30

Crystal

Answer 30

Region in a solid where the particles are arranged in a regular and continuous way

Question 31

Crystals and metals

Answer 31

metal behaviour depends on size and arrangement of crystals

Question 32

Smaller crystals

Answer 32

Result in a harder, but more brittle metal

less free movement of layers of cation over each other

Question 33

Heat treatment

Answer 33

When heated, the individual crystals merge and when the metal is allowed to cool, the crystals reform
rate of cooling determines how large the new crystal will be

Question 34

Quenching

Answer 34

Faster cooling

leads to smaller crystals

Question 35

Annealing

Answer 35

Slower cooling

allows more time for crystals to grow larger

Question 36

metallic nano materials

Answer 36

have very different properties when compared to a bulk sample of same metal because they have a very high surface area to volume ratio