CBSE
Multiple Choice Questions'Metals are usually not found as nitrates in their ores'
Out of the following two (a and b) reasons which isare/are true for the above observation?
I. Metal nitrates are highly unstable.
II.Metal nitrates are highly soluble in water.
I and II are true
I and II are false
I is false but II is true
I is false but II is true
In the extraction of copper from its sulphide ore, the metal finally obtained by the reduction of cuprous oxide with
Iron (II) sulphide
Carbon monoxide
Copper (I) sulphide
Copper (I) sulphide
Identify the alloy containing a non-metal as a constituent in it.
Invar
Steel
Bell metal
Bell metal
Match items of Columns I with the items of Columns II and assign the correct code.
|
Column I |
Column II |
|
A.Cyanide process |
1.Ultrapure Ge |
|
B. Froth floatation process |
2.Dressing of ZnS |
|
C.Electrolytic reduction |
3.Extraction of Al |
|
D.Zone refining |
4.Extraction of Au |
|
|
5.Purification of Ni |
|
A
|
B
|
C
|
D
|
|
A
|
B
|
C
|
D
|
|
A
|
B
|
C
|
D
|
|
A
|
B
|
C
|
D
|
Which of the following pairs of metals is purified by van Arkel method?
Zr and Ti
Ag and Au
Ni and Fe
Ni and Fe
Roasting of sulphides gives the gas X as a by-product. This is a colourless gas with the choking smell of burnt sulphur and causes great damage to respiratory organs as a result of acid rain. Its aqueous solution is acidic acts as a reducing agent and its acid has never been isolated. The gas X is
H2S
SO2
CO2
CO2
Which one of the following is a mineral of iron?
Malachite
Cassiterite
Pyrolusite
Magnetite
In the extraction of copper from its sulphide ore, the metal is finally obtained by the reduction of cuprous oxide with
Copper (I) sulphide (Cu2S)
sulphur dioxide (SO2)
Iron sulphide (FeS)
Iron sulphide (FeS)
Which of the following elements is present as the impurity to the maximum extent in the big iron?
Carbon
Silicon
Phosphorus
Phosphorus
Aluminium is extracted from alumina (Al2O3) by electrolysis of a molten mixture of
Al2O3 +HF +NaAlF4
Al2O3 + CaF2 +NaAlF4
Al2O3 +Na3AlF6 +CaF2
Al2O3 +KF +Na3AlF6
