unit one - 1.3 (metals and their uses)

Question 1

what are ores

Answer 1

naturally occurring rocks that provide an economic starting point for the manufacture of metals

Question 2

what is iron ore used to make

Answer 2

iron and steel

Question 3

aluminium and titanium are..

Answer 3

useful metals, but expensive to produce

Question 4

metals can be mixed to form

Answer 4

alloys

Question 5

metal ores are obtained by.. what does this involve

Answer 5

obtained by mining, which involves digging up large amounts of rock and processing it

Question 6

what happens after ores are mined

Answer 6

they could be concentrated and then the metal is purified and extracted

Question 7

most metals are found as compounds which require..

Answer 7

chemical reactions to extract the metals

Question 8

metals that are less reactive are extracted from their oxides by

Answer 8

reduction e.g. iron oxide in the blast furnace is reduced to iron

Question 9

metals that are more reactive are extracted from their oxide by

Answer 9

electrolysis, uses large amount of energy so is therefore expensive

Question 10

copper can be extracted from copper-rich ores by

Answer 10

heating the ores in a furnace (smelting). the copper is then purified by electrolysis (supply is limited)

Question 11

phytomining

Answer 11

uses plants to absorb metal compounds and then plants are burnt which separates the ashes and metal compounds

Question 12

bioleaching

Answer 12

uses bacteria to produce leachate solutions that contain metal compounds

Question 13

copper can be obtained from solutions of copper salts by electrolysis or

Answer 13

by displacement using scrap iron

Question 14

aluminium and titanium cannot be extraction from their oxides by reduction with carbon because

Answer 14

there are many stages in the processes and large amounts of energy are required - which makes the process very expensive

Question 15

during electrolysis, positive ions move towards the negative electrode called the

Answer 15

cathode

Question 16

we should recycle materials because

Answer 16

extracting them uses limited resources and is expensive (in terms of energy and effect on the environment)

Question 17

iron from the blast furnace contains 96% iron so is

Answer 17

brittle because of its impurities, so it has limited uses

Question 18

most iron is converted into steel which is

Answer 18

an alloy of iron and carbon

Question 19

low-carbon steels are

Answer 19

easily shaped unlike high-carbon steels which are hard, but stainless steels are resistant to corrosion

Question 20

most metals are alloys because

Answer 20

pure copper, gold, aluminium and iron are too SOFT, so they are mixed with materials to make them harder for everyday use.

Question 21

blast furnace iron is used as cast iron because of its

Answer 21

strength in compression

Question 22

elements in the middle of the periodic table are called

Answer 22

transition metals because they are good conductors of heat and electricity and can be bent/hammered into shape

Question 23

transition metals are useful as

Answer 23

construction materials and making things that allow heat/ electricity to pass through easily

Question 24

copper has properties that make it useful for plumbing and electrical wiring.. what are they?

Answer 24

good conductor of heat/electricity
can be bent but is hard enough to be used to make pipes/tanks
does not react with water

Question 25

low density/ resistance to corrosion make which 2 metals useful

Answer 25

aluminum and titanium