metallurgy

Question 1

elements occurring in free state

Answer 1

carbon, gold sulfur and noble gases

Question 2

most abundant metal

Answer 2

aluminun

Question 3

ores of aluminum

Answer 3

bauxite, kaolinite

Question 4

Haematite and Magnetite are

I

Answer 4

Fe2O3, Fe3O4

Question 5

Siderite

Answer 5

FeCO3

Question 6

Iron pyrites

Answer 6

FeS2

Question 7

Copper pyrites

Answer 7

CuFeS2

Question 8

Malachite

Answer 8

CuCO3.Cu(OH)2

Question 9

Cuprite

Answer 9

Cu2O

Question 10

Copper glance

Answer 10

Cu2S

Question 11

Zinc blende or Sphalerite

Answer 11

ZnS

Question 12

Calamine

Answer 12

ZnCO3

Question 13

Zincite

Answer 13

ZnO

Question 14

Froth Floatation Method used for —————- ores

Answer 14

sulfide

Question 15

Depressant used to separate ZnS and PbS

Answer 15

NaCN

Question 16

leaching of bauxite gives

Answer 16

Sodium aluminate

Al2O3 (s) + 2NaOH(aq) + 3H2O(l) → 2NaAl(OH)4

Question 17

CO2 reaction with sodium aluminate after leaching gives

Answer 17

Hydrated Al2O3

2NaAl(OH)4 + CO2 (g) → Al2O3.xH2O(s) + 2NaHCO3 (aq)

Question 18

silver and gold are leached with

Answer 18

NaCN or KCN

4M(s) + 8CN–(aq)+ 2H2O(aq) + O2(g) → 4[M(CN)2– (aq) +4OH–(aq) (M= Ag or Au)

Question 19

calcination of ZnCO3 gives

Answer 19

ZnO

ZnCO3 (s) ——ZnO(s) + CO2 (g)

Question 20

The sulphide ores of copper are roasted in

Answer 20

reverberatory furnace

Question 21

‘flux’ is added which combines with ‘gangue’ to form

Answer 21

Slag

Question 22

Copper matte consists of

Answer 22

Cu2S and FeS

Question 23

SO2 produced in reverberatory furnace us used in

Answer 23

Preparation of H2SO4