JEE Chemistry General Principles And Processes Of Isolation Of Elements MCQs Set 17

Multiple Choice Questions (MCQs) for JEE Chemistry: General Principles and Processes Of Isolation Of Elements

Review structured MCQ sets for JEE Chemistry General Principles and Processes Of Isolation Of Elements. Built according to official JEE guidelines, these downloadable questions support daily revision and core concept reinforcement.

Practice General Principles and Processes Of Isolation Of Elements MCQs for JEE Chemistry

Navigate directly to the 50 objective questions for General Principles and Processes Of Isolation Of Elements using the digital viewer below. Each practice set includes verified answer keys, allowing students to instantly cross-check their work and identify areas requiring further revision.

Multiple Choice Questions

Question 1: Sodium cyanide solution is used as electrolyte in gold plating instead of nitric acid because
(a) NaCN is a better solvent for gold ions
(b) gold deposition from nitric acid is slow
(c) cyanide forms a complex with gold, helping uniform deposition
(d) cyanide binds impurity ions
Show Answer & Explanation

Answer: (c) cyanide forms a complex with gold, helping uniform deposition

Explanation:
1. The dicyanoaurate complex releases gold ions slowly, giving a smooth uniform deposit.

Teacher's Note:
1. Complexation controls the concentration of free metal ions.

Question 2: Complexes formed in the cyanide process are (i) \( \ce{[Au(CN)2]^-} \) (ii) \( \ce{[Ag(CN)2]^-} \) (iii) \( \ce{[Cu(CN)4]^{2-}} \) (iv) \( \ce{[Zn(CN)4]^{2-}} \)
(a) (i), (ii) and (iv)
(b) (i) and (iii)
(c) (ii) and (iii)
(d) (i), (ii), (iii) and (iv)
Show Answer & Explanation

Answer: (a) (i), (ii) and (iv)

Explanation:
1. Au and Ag dissolve as dicyano complexes, and zinc displaces them forming tetracyanozincate.

Teacher's Note:
1. Copper is not extracted by the cyanide process.

Question 3: Van Arkel method of purification converts the metal into
(a) a volatile stable compound
(b) a volatile unstable compound
(c) a non-volatile stable compound
(d) none of these
Show Answer & Explanation

Answer: (b) a volatile unstable compound

Explanation:
1. The metal iodide is volatile but unstable at high temperature, so it decomposes on a hot filament.

Teacher's Note:
1. This gives very pure Ti, Zr and Hf.

Question 4: Calcium silicate slag formed in the iron blast furnace (i) does not dissolve in molten iron; (ii) floats on molten iron; (iii) is used in cement and building material; (iv) prevents re-oxidation of molten iron
(a) (i), (ii), (iii) and (iv)
(b) (i) and (ii) only
(c) (ii) and (iii) only
(d) (i), (iii) and (iv) only
Show Answer & Explanation

Answer: (a) (i), (ii), (iii) and (iv)

Explanation:
1. Slag is immiscible with iron, lighter, protects the metal from air and is a useful by-product.

Teacher's Note:
1. Blast furnace slag is a cement raw material.

Question 5: Blister copper is
(a) impure copper
(b) obtained by self-reduction during bessemerisation
(c) both of these are correct
(d) neither is correct
Show Answer & Explanation

Answer: (c) both of these are correct

Explanation:
1. Blister copper (about 98 percent Cu) is the product of self-reduction in the converter and is impure.

Teacher's Note:
1. It is refined by electrolysis to 99.9 percent purity.

Question 6: Which are correct reduction processes? (i) \( \ce{Fe2O3 + CO -> Fe + CO2} \) (ii) \( \ce{ZnO + C -> Zn + CO} \) (iii) \( \ce{2Cu2O + Cu2S -> 6Cu + SO2} \) (iv) \( \ce{PbO + C -> Pb + CO} \)
(a) All four
(b) (i) and (ii) only
(c) (ii) and (iii) only
(d) (i) and (iv) only
Show Answer & Explanation

Answer: (a) All four

Explanation:
1. All are standard reductions in the extraction of iron, zinc, copper and lead.

Teacher's Note:
1. (iii) is a self-reduction.

Question 7: Roasting of copper pyrites is done (i) to remove moisture; (ii) to oxidise free sulphur and antimony and arsenic; (iii) to convert pyrites completely to \( \ce{Cu2O} \) and FeO; (iv) to remove volatile organic impurities
(a) (i), (ii) and (iv)
(b) (i), (ii), (iii) and (iv)
(c) (ii) and (iii)
(d) (iii) only
Show Answer & Explanation

Answer: (a) (i), (ii) and (iv)

Explanation:
1. Roasting is done in limited oxidation: iron sulphide is converted to FeO but copper sulphide is left as \( \ce{Cu2S} \) (not completely oxidised).

Teacher's Note:
1. Copper sulphide is purposely not oxidised so that it can pass to the matte.

Question 8: In roasting,
(a) the ore becomes porous
(b) non-metals leave as volatile oxides
(c) all of these
(d) moisture is removed
Show Answer & Explanation

Answer: (c) all of these

Explanation:
1. Roasting dries the ore, oxidises As, S and P to volatile oxides and makes it porous for easy reduction.

Teacher's Note:
1. Roasting is done in excess air in a reverberatory furnace.

Question 9: Aluminium is purified by
(a) Serpeck's process
(b) Hoop's process
(c) Hall-Heroult process
(d) Baeyer's process
Show Answer & Explanation

Answer: (b) Hoop's process

Explanation:
1. Hoop's process is an electrolytic refining with three molten layers (impure Al at the bottom, fluoride electrolyte in the middle, pure Al on top).

Teacher's Note:
1. Hall-Heroult is for extraction, and Baeyer's and Serpeck's are for purification of bauxite.

Question 10: How many of these metals can be extracted by carbon reduction: Pb, Fe, Zn, Al?
(a) 2
(b) 4
(c) 1
(d) 3
Show Answer & Explanation

Answer: (d) 3

Explanation:
1. Pb, Fe and Zn oxides are reduced by carbon; Al is not.

Teacher's Note:
1. Metals below Al in the Ellingham diagram can be reduced by carbon.

Question 11: How many of the following ores involve calcination in extraction: dolomite, malachite, calcite, copper pyrites, sylvine, cryolite, siderite, iron pyrites, argentite?
(a) 2
(b) 4
(c) 3
(d) 5
Show Answer & Explanation

Answer: (b) 4

Explanation:
1. Carbonates and hydroxides undergo calcination: dolomite, malachite, calcite and siderite.

Teacher's Note:
1. Sulphides are roasted, halides are not heated for this purpose.

Question 12: A sulphide ore like ZnS is first roasted to oxide before reduction with carbon because
(a) the free energies of formation of most sulphides are greater than that of \( \ce{CS2} \) so carbon cannot reduce them
(b) an oxide is generally less stable than a sulphide
(c) no reducing agent is suitable
(d) a sulphide ore cannot be reduced at all
Show Answer & Explanation

Answer: (a) the free energies of formation of most sulphides are greater than that of \( \ce{CS2} \) so carbon cannot reduce them

Explanation:
1. Carbon is not able to reduce metal sulphides because the reaction \( \ce{MS + C -> M + CS2} \) is not favourable; the oxides are reduced because \( \ce{CO2} \) is more stable.

Teacher's Note:
1. The roasting step converts sulphide to oxide, and the oxide is then reduced.

Question 13: In the electrolytic refining of lead, the impurities Sb, Cu, Ag and Au are found
(a) in the anode mud
(b) on the anode
(c) in the electrolyte
(d) in the cathode mud
Show Answer & Explanation

Answer: (a) in the anode mud

Explanation:
1. Less electropositive impurities do not dissolve and fall to the bottom as anode mud (unlike more active metals, which go into solution).

Teacher's Note:
1. Anode mud is a source of valuable precious metals.

Question 14: When metal M is treated with NaOH, a white gelatinous precipitate X forms, soluble in excess NaOH; X on strong heating gives an oxide used as an adsorbent in chromatography. M is
(a) Zn
(b) Fe
(c) Ca
(d) Al
Show Answer & Explanation

Answer: (d) Al

Explanation:
1. Aluminium hydroxide dissolves in excess alkali to give aluminate, and heating gives \( \ce{Al2O3} \), the common chromatographic adsorbent.

Teacher's Note:
1. Zn(OH)2 also dissolves in excess alkali but ZnO is not the chromatographic adsorbent.

Question 15: Aluminium is extracted by the electrolysis of
(a) alumina
(b) bauxite
(c) alumina mixed with molten cryolite
(d) molten cryolite
Show Answer & Explanation

Answer: (c) alumina mixed with molten cryolite

Explanation:
1. Molten cryolite dissolves alumina, giving a conducting melt at low temperature.

Teacher's Note:
1. Alumina alone melts above 2300 K.

Question 16: Roasting is carried out for how many of these ores: galena, iron pyrites, copper glance, calamine, siderite?
(a) 2
(b) 4
(c) 5
(d) 3
Show Answer & Explanation

Answer: (d) 3

Explanation:
1. Galena, iron pyrites and copper glance are sulphides and are roasted; calamine and siderite are carbonates and are calcined.

Teacher's Note:
1. Count the sulphides.

Question 17: In Parke's process for desilverising argentiferous lead,
(a) lead is removed by electrolysis
(b) silver is oxidised to its oxide and slagged off
(c) molten zinc dissolves the silver and the zinc-silver alloy is later distilled
(d) silver is volatilised with carbon monoxide as a carbonyl
Show Answer & Explanation

Answer: (c) molten zinc dissolves the silver and the zinc-silver alloy is later distilled

Explanation:
1. Zinc is immiscible with lead but dissolves silver, so the zinc-silver alloy is skimmed off and zinc is distilled away.

Teacher's Note:
1. Cupellation is then used for removing small traces of lead from the silver.

Question 18: Which ore is best concentrated by froth flotation?
(a) Cassiterite
(b) Malachite
(c) Magnetite
(d) Galena
Show Answer & Explanation

Answer: (d) Galena

Explanation:
1. Sulphides like galena float. The others are oxide or carbonate ores.

Teacher's Note:
1. Froth flotation is for sulphide ores.

Question 19: Which of these are manufactured by electrolysis of their fused salts? (i) copper (ii) sodium (iii) aluminium (iv) platinum
(a) (ii) and (iii) only
(b) (i) and (iv) only
(c) (i), (ii) and (iii)
(d) (iii) only
Show Answer & Explanation

Answer: (a) (ii) and (iii) only

Explanation:
1. Sodium (from NaCl) and aluminium (from alumina in cryolite) are electropositive and need fused-salt electrolysis. Copper is obtained by reduction or aqueous electrolysis, and platinum is native.

Teacher's Note:
1. Rule: very reactive metals are made by fused-salt electrolysis.

Question 20: In the Hall-Heroult process for aluminium,
(a) cryolite lowers the melting point of alumina and increases conductivity
(b) Al is obtained at the cathode and CO2 (with CO) at the anode
(c) both of these are correct
(d) neither is correct
Show Answer & Explanation

Answer: (c) both of these are correct

Explanation:
1. Alumina melts at over 2000 degrees Celsius; dissolved in molten cryolite it can be electrolysed near 1230 K. Aluminium collects at the cathode and carbon anodes are oxidised to CO and CO2.

Teacher's Note:
1. The cell has a graphite-lined steel tank as cathode.

Question 21: Stainless steel contains iron along with
(a) Ni, Cu, Mn
(b) Cr, Ni, C
(c) Ni, Zn, Cr
(d) Cr, Cu, C
Show Answer & Explanation

Answer: (b) Cr, Ni, C

Explanation:
1. Stainless steel is an alloy of iron with chromium, nickel and a little carbon.

Teacher's Note:
1. Chromium forms the protective oxide layer.

Question 22: Cryolite, \( \ce{Na3AlF6} \), is used in the electrolysis of alumina
(a) to lower the melting point of alumina and improve conductivity
(b) to increase the melting point
(c) for electrolytic purification of alumina
(d) to decrease electrical conductivity
Show Answer & Explanation

Answer: (a) to lower the melting point of alumina and improve conductivity

Explanation:
1. Cryolite dissolves alumina and lowers the operating temperature to about 1200 K.

Teacher's Note:
1. It also makes the melt conducting.

Question 23: The number of reducing agents involved in extracting pig iron from haematite in the blast furnace is
(a) 4
(b) 2
(c) 1
(d) 3
Show Answer & Explanation

Answer: (b) 2

Explanation:
1. Carbon (coke) and carbon monoxide (formed from it) are the two reducing agents.

Teacher's Note:
1. CO reduces in the upper part and C in the lower part of the furnace.

Question 24: In the blast furnace for iron, the upper layer at the bottom mainly contains
(a) \( \ce{Fe2O3} \)
(b) spongy iron
(c) \( \ce{CaSiO3} \) (slag)
(d) \( \ce{FeSiO3} \)
Show Answer & Explanation

Answer: (c) \( \ce{CaSiO3} \) (slag)

Explanation:
1. Molten slag is less dense than molten iron, so it floats on top and is tapped separately.

Teacher's Note:
1. In the blast furnace the flux is limestone and the slag is calcium silicate.

Question 25: How many of the following reactions do NOT take place in the Bessemer converter: (1) \( \ce{2Cu2O + Cu2S -> 6Cu + SO2} \) (2) \( \ce{2CuFeS2 + O2 -> Cu2S + FeS + SO2} \) (3) \( \ce{2Cu2S + 3O2 -> 2Cu2O + 2SO2} \) (4) \( \ce{2FeS + 3O2 -> 2FeO + 2SO2} \)?
(a) 3
(b) 4
(c) 2
(d) 1
Show Answer & Explanation

Answer: (d) 1

Explanation:
1. (2) is a roasting reaction in the reverberatory furnace; the others (partial oxidation, self-reduction, removal of FeS as slag) take place in the converter.

Teacher's Note:
1. Bessemerisation is the final stage producing blister copper.

Free study material for Chemistry

Practice MCQs for JEE Chemistry General Principles and Processes Of Isolation Of Elements

Download Multiple Choice Questions: General Principles and Processes Of Isolation Of Elements (JEE Chemistry)

Test your conceptual understanding of General Principles and Processes Of Isolation Of Elements with these targeted multiple-choice questions. Designed in alignment with the latest JEE curriculum for JEE Chemistry, these problem sets build accuracy and prepare students for objective exams.

Concept Clarification for General Principles and Processes Of Isolation Of Elements

Cross-reference your completed choices with comprehensive NCERT solutions for JEE Chemistry to ensure absolute clarity across all sub-topics in this chapter.

Additional Study Resources for JEE Chemistry

Explore our broader library of printable assignments, chapter notes, and mock tests designed to support continuous revision and secure higher marks in JEE assessments.

FAQs

Where can I access latest JEE Chemistry General Principles And Processes Of Isolation Of Elements MCQs Set 17?

You can get most exhaustive JEE Chemistry General Principles And Processes Of Isolation Of Elements MCQs Set 17 for free on StudiesToday.com. These MCQs for JEE Chemistry are updated for the 2026-27 academic session as per JEE examination standards.

Are Assertion-Reasoning and Case-Study MCQs included in the Chemistry JEE material?

Yes, our JEE Chemistry General Principles And Processes Of Isolation Of Elements MCQs Set 17 include the latest type of questions, such as Assertion-Reasoning and Case-based MCQs. 50% of the JEE paper is now competency-based.

How do practicing Chemistry MCQs help in scoring full marks in JEE exams?

By solving our JEE Chemistry General Principles And Processes Of Isolation Of Elements MCQs Set 17, JEE students can improve their accuracy and speed which is important as objective questions provide a chance to secure 100% marks in the Chemistry.

Do you provide answers and explanations for JEE Chemistry General Principles And Processes Of Isolation Of Elements MCQs Set 17?

Yes, Chemistry MCQs for JEE have answer key and brief explanations to help students understand logic behind the correct option as its important for 2026 competency-focused JEE exams.

Can I practice these Chemistry JEE MCQs online?

Yes, you can also access online interactive tests for JEE Chemistry General Principles And Processes Of Isolation Of Elements MCQs Set 17 on StudiesToday.com as they provide instant answers and score to help you track your progress in Chemistry.