metals and alloys

Question 1

what are the 3 physical properties of metals

Answer 1

good conductor of heat and electricity
high density
high melting and boiling point

Question 2

what are the characteristics of pure metals

Answer 2

malleable and ductile
atoms are of same size and arranged in neat layers
when force is applied, a layer of atoms can slide over each other easily

Question 3

what are the characteristics of alloys

Answer 3

stronger and harder than a pure metal
atoms are of different sizes from different metals thus disrupts orderly arrangement
when force is applied, a layer of atoms cannot slide pat each other easily

Question 4

define alloys

Answer 4

is a mixture of metals with other elements

Question 5

why do we use alloys instead of metals

Answer 5

stronger and harder
more resistant to corrosion
improve the appearance of metals
lower melting points of metals

Question 6

what are the 4 types of alloys

Answer 6

brass
bronze
steel
stainless steel

Question 7

brass is made up of…

Answer 7

copper and zinc

Question 8

bronze is made up of…

Answer 8

copper and tin

Question 9

steel is made up of…

Answer 9

iron and carbon

Question 10

stainless steel is made up of…

Answer 10

iron, carbon and chromium

Question 11

brass is used to make…

Answer 11

musical instrument

Question 12

bronze is used to make…

Answer 12

coins and sculptures

Question 13

steel is used to make…

Answer 13

construct railways and buildings

Question 14

stainless steel is used to make…

Answer 14

cutlery and surgical instruments

Question 15

name all the elements in the reactive series

Answer 15

please stop calling me a crappy zebra, i (like) horses cow sheep and goat 
Potassium
Sodium
Calcium
Magnesium
Aluminium
Carbon
Zinc
Iron
Hydrogen
Copper
Silver
Gold

Question 16

which are the elements that use electrolysis for the methods of extraction

Answer 16

P - A
Potassium
Sodium 
Calcium
Magnesium
Aluminium

Question 17

which of the elements that are used for extraction

Answer 17

carbon

Question 18

which are the elements that use extraction of metals using carbon

Answer 18

Z - S
Zinc
Iron
Hydrogen
Copper
Silver

Question 19

which element is found uncombined

Answer 19

Gold

Question 20

which elements react with acid

Answer 20

P - H
Potassium
Sodium
Calcium
Magnesium
Aluminium
Carbon
Zinc
Iron
Hydrogen

Question 21

which elements do not react with acid

Answer 21

C - G
Copper
Silver
Gold

Question 22

which elements react with cold water

Answer 22

P - M 
Potassium
Sodium
Calcium
Magnesium

Question 23

which elements do not react with cold water

Answer 23

A - G 
Aluminium
Carbon
Zinc
Iron
Hydrogen
Copper
Silver
Gold

Question 24

which elements react with steam

Answer 24

M - G
Magnesium
Aluminium
Carbon
Zinc
Iron
Hydrogen
Copper
Silver
Gold

Question 25

which elements are too dangerous to react with steam

Answer 25

P - C Potassium Sodium Calcium

Question 26

which elements do not react with steam

Answer 26

``` C - G Carbon Zinc Iron Hydrogen Copper Silver Gold ```

Question 27

what is displacement of metals

Answer 27

a more reactive metal displaces a less reactive metal from its solution

Question 28

what are the reactants used to extract pure metals from their metal ores using blast furnace

Answer 28

limestone haematite coke hot air

Question 29

what are the products when extracting pure metals from their metal ores using blast furnace

Answer 29

waste gases slag molten _____ (iron etc)

Question 30

what is the function of limestone

Answer 30

to remove acidic impurities

Question 31

what are waste gases formed

Answer 31

78% of nitrogen | carbon dioxide

Question 32

what are the 4 stages of the process the reactants went through

Answer 32

1. produce carbon dioxide 2. produce carbon dioxide 3. reduce haematite to produce molten ____ (iron etc) 4. remove acidic impurities, silicon dioxide, SiO2 and produce molten slag

Question 33

what is the use of molten slag

Answer 33

to pave roads

Question 34

what are the chemical equations of the 4 stages of reactants

Answer 34

C + O2 --> CO2 CO2 + C (add more coke) --> 2CO FeO3 + 3CO (carbon monoxide) --> 2Fe + 3CO2 CaO + SiO2 --> CaSiO3

Question 35

all metals corrode except...

Answer 35

iron

Question 36

what are the conditions for rusting to take place

Answer 36

water and oxygen

Question 37

when iron rusts, it forms...

Answer 37

iron (III) oxide

Question 38

what are the 2 ways to speed up rusting process

Answer 38

sodium chloride | acidic substances

Question 39

what are the 3 methods to prevent rusting

Answer 39

painting sacrificial protection galvanising with zinc

Question 40

explain how painting prevents rusting

Answer 40

it coats and provide a protective layer to prevent iron from coming in contact with water and oxygen

Question 41

one disadvantage of painting to prevent rusting

Answer 41

the paint may be scratched thus rust will take place under the painted surface

Question 42

explain how sacrificial protection prevent rusting

Answer 42

when 2 metals are together, more reactive metal will corrode in places of less reactive metal

Question 43

why do we recycle

Answer 43

as metals are in high demand as they are limited resources

Question 44

what are the advantages of recycling

Answer 44

conserve earth's finite natural resources | reduces air pollution compared to extraction as it releases toxic gases to the environment

Question 45

what are the disadvantages of recycling

Answer 45

recycling processes releases harmful gases = air pollution | it is costly (transport, sort, separate and clean) very high costs = not worthwhile

Question 46

metal + cold water -->

Answer 46

metal hydroxide + hydrogen gas

Question 47

metal + steam -->

Answer 47

metal oxide + hydrogen gas

Question 48

why is molten iron formed lower than molten slag in he blast furnace

Answer 48

molten iron is denser than molten slag | thus it is found at the bottom