CBSE
Which ofthe following pairs of elements can not form an alloy ?
Zn , Cu
Fe , Hg
Fe , C
Hg , Na
Which metallurgy does not involve leaching ?
Fe
Ag
Au
Al
Assertion : Hydrometallurgy involves dissolving the ore in a suitable reagent followed by precipitation by a more electropositive metal.
Reason : Copper is extracted by hydrometallurgy.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false
If both assertion and reason are false.
The temperature of the slag zone in metallurgy of iron using blast furnace is :
1200-1500°C
1500-1600°C
400-700°C
800-1000°C
Percentage of silver in the alloy German siiver is:
0%
1.0%
2.5%
1.5%
One of the following metals forms a volatile compound and this property is taken advantage for its extraction. This metal is:
iron
nickel
cobalt
tungsten
Gold is extracted by hydrometallurgical process, based on its property :
of being electropositive
of being less reactive
to form complexes which are water soluble
to form salts which are water soluble
Which of the following elements is present as the impurity to the maximum extent in pig iron ?
Phosphorus
Manganese
Carbon
Silicon
Which of the following is coinage metal?
Cu
Sn
Zn
Pb
The present undesirable matrix in mineral is called as :
flux
slag
gangue
alloy