In metallurgy the term “gangue” is used for:
Contamination of undesired earthy materials
Contamination of metals, other than desired metal
Minerals which are naturally occurring in pure form
Magnetic impurities in an ore
Refining using liquation method is the most suitable for metals with:
Match List I with List II. Choose the correct answer from the options given below:
Match List-I with List – II:
Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R.Assertion A : The reduction of a metal oxide is easier if the metal formed is in liquid state than solid state.Reason R : The value of \( \Delta G^\ominus \) becomes more on negative side as entropy is higher in liquid state than solid state.In the light of the above statements, choose the most appropriate answer from the options given below.
The compound(s) that is(are) removed as slag during the extraction of copper is: I. \( \mathrm{CaO} \) II. \( \mathrm{FeO} \) III. \( \mathrm{Al_2O_3} \) IV. \( \mathrm{ZnO} \) V. \( \mathrm{NiO} \) Choose the correct answer from the option given below:
Given are two statements one is labelled as Assertion A and other is labelled as Reason R.Assertion A: Magnesium can reduce \( \mathrm{Al_{2}O_{3}} \) at a temperature below \( 1350^{\circ}\mathrm{C} \), while above \( 1350^{\circ}\mathrm{C} \) Aluminium can reduce \( \mathrm{MgO} \).Reason R: The melting and boiling points of magnesium are lower than those of aluminium.In light of the above statements, choose most appropriate answer from the options given below:
Addition of \( \mathrm{H_2SO_4} \) to \( \mathrm{BaO_2} \) produces:
Which of the following chemical reactions represents Hall-Heroult Process?
Given below are two statements:Statement I: According to the Ellingham diagram, any metal oxide with higher \( \Delta G^\circ \) is more stable than the one with lower \( \Delta G^\circ \).Statement II: The metal involved in the formation of oxide placed lower in the Ellingham diagram can reduce the oxide of a metal placed higher in the diagram.In the light of the above statements, choose the most appropriate answer from the options given below:
Given below are two statements.Statement I: During electrolytic refining, blister copper deposits precious metals.Statement II: In the process of obtaining pure copper by electrolysis method, copper blister is used to make the anode.In the light of the above statements, choose the correct answer from the options given below.
The role of depressants in ‘Froth Floatation method’ is to:
Given below are two statements:Statement I: In ‘Lassaigne’s Test’, when both nitrogen and sulphur are present in an organic compound, sodium thiocyanate is formed.Statement II: If both nitrogen and sulphur are present in an organic compound, then the excess of sodium used in sodium fusion will decompose the sodium thiocyanate formed to give \( \mathrm{NaCN} \) and \( \mathrm{Na_2S} \).In the light of the above statements, choose the most appropriate answer from the options given below:
Which of the following methods are not used to refine any metal?(I) Liquation (II) Calcination(III) Electrolysis (IV) Leaching(V) DistillationChoose the correct answer from the options given below:
In the metallurgical extraction of copper, following reaction is used:\( \mathrm{FeO} + \mathrm{SiO_2} \rightarrow \mathrm{FeSiO_3} \) \( \mathrm{FeO} \) and \( \mathrm{FeSiO_3} \) respectively are.
In isolation of which one of the following metals from their ores, the use of cyanide salt is not commonly involved?