metallurgy

Question 1

minerals

Answer 1

naturally occuring substances which are generally mixed with other subsatnces like soil,sand ,mud etc

Question 2

gangue or matrix

Answer 2

earthy impurities present in minerals

Question 3

ore

Answer 3

minerals which are extracted commercially at a comparatively lower cost

Question 4

main ore of aluminium

Answer 4

bauxite - al203.2h20

Question 5

main ore of iron

Answer 5

haematite-fe2o3

Question 6

main ore of zinc

Answer 6

zinc blende-zns

Question 7

bauxite

Answer 7

hydrated aluminium oxide-al2o3.2h2o

Question 8

cryolite

Answer 8

sodium aluminium fluoride-na3alf6

Question 9

corundum

Answer 9

anhydrous aluminium oxide-al2o3

Question 10

red haematite

Answer 10

fe2o3

Question 11

brown haematite

Answer 11

2fe2o3.3h2o

Question 12

mangnetite

Answer 12

triferric tetraoxide- fe3o4

Question 13

iron pyrites

Answer 13

iron disulphide-fes2

Question 14

siderite

Answer 14

ferrous carbonate-feco3

Question 15

zinc blende

Answer 15

zinc sulphide-zns

Question 16

zincite

Answer 16

zinc oxide-zno

Question 17

calamine

Answer 17

zinc carbonate-znco3

Question 18

metallurgy

Answer 18

used for extraction of metals in their pure form from their ores
deals with production and purification of metals and manufacture of alloys

Question 19

pulverisation

Answer 19

process by which ores get crushed into fine powder in big jaw crushers and ball mills

Question 20

stages involved in extraction of metals

Answer 20

ore
crushing/grinding
conc
roasting/calcination
reduction
refining
pure metal

Question 21

types of conc

Answer 21

gravity seperation
froth floatation
magnetic seperation
leaching/chemical method

Question 22

types of reduction

Answer 22

electrolytic and chemical

Question 23

concentration

Answer 23

process of removing gangue present in an ore

Question 24

hydraulic washing/gravity separation

Answer 24

difference in densities of the ore and gangue is the main criteria

oxides of iron and tin

Question 25

magnetic separation

Answer 25

mangnetic property of ore

tin stone which contains ferric oxide as impurity

Question 26

froth floatation

Answer 26

depends on the preferential wettability of ore with pine oil and gangue by water

zinc blende zns and galena pbs

Question 27

roasting

Answer 27

heating conc ore to a high temp in presence of air

Question 28

calcination

Answer 28

if an ore is a carbonate or hydrated oxide is heated in the absence of air at high temp but insufficient to melt the ore

Question 29

al colour

Answer 29

silvery white

Question 30

al ram

Answer 30

27

Question 31

al atm no

Answer 31

13

Question 32

aluminium is extracted from

Answer 32

bauxite

Question 33

bauxite contains

Answer 33

60% of al2o3 rest being sand,ferric oxide and titanium oxide

Question 34

conced or purified by

Answer 34

leaching or chemical method

Question 35

cryolite use

Answer 35

lowers temp from 2050-950
enhances conductivity

Question 36

fluorspar and cryolite

Answer 36

increases conductivity
acts as a solvent for electrolytic mixture

Question 37

powdered coke use

Answer 37

reduces heat loss by radiation
prevents burning at anode

Question 38

alloys

Answer 38

homogenous mixture of 2 or more metals with certain non metallic elements

Question 39

aluminium-duralumin

Answer 39

95-Al
4-cu
0.5-mg
0.5 mn
-bodies of aircraft
-light tools
-pressure cooker

Question 40

iron-stainless steel

Answer 40

73-fe
18-cr
8-ni
1-c
-utensils
-cutlery
-ornaments
-surgical instruments

Question 41

brass-zincopper

Answer 41

60-70-cu
40-30-zn
-musical instruments
-screws and handles
-marine engines

Question 42

bronze-zincopper

Answer 42

80-cu
18-sn
2-zn
-statues
-medals
-coins

Question 43

solder or fuse metals

Answer 43

50-pb
50-sn
-soldering purpose
-fuse printing blocks