Q60. The Kudremukh mines in Karnataka are primarily known for the extraction of which mineral?
[SSC CGL, 18 September 2025, Shift 1]
(A) Bauxite
(B) Limestone
(C) Iron ore
(D) Copper
𝐀𝐧𝐬𝐰𝐞𝐫: (C) Iron ore
Explanation: Kudremukh in Karnataka is known for magnetite-rich iron-ore deposits. The ore was historically concentrated and transported for pellet production and export. Magnetite has the formula Fe₃O₄ and is notable for its magnetic properties.
Q59. Which one of the following metals is widely extracted by electrolysis of its molten compound?
[UPSC CDS II (General Knowledge), 14 September 2025]
(A) Cu
(B) Au
(C) Sn
(D) Na
𝐀𝐧𝐬𝐰𝐞𝐫: (D) Na
Explanation: Sodium is highly reactive, so ordinary carbon reduction is unsuitable for its industrial extraction. In the Downs process, molten sodium chloride is electrolysed to yield sodium metal at the cathode and chlorine gas at the anode.
Q58. Which of the following minerals are found in Kerala?
[SSC Selection Post (Higher Secondary Level), 2 August 2025, Shift 2]
(A) Monazite, thorium and bauxite clay
(B) Iron ore, coal and gold
(C) Copper, limestone and gypsum
(D) Uranium, petroleum and mica
𝐀𝐧𝐬𝐰𝐞𝐫: (A) Monazite, thorium and bauxite clay
Explanation: Kerala’s coastal placer sands are well known for monazite, a phosphate mineral containing rare-earth elements and often thorium. Such heavy-mineral sands are concentrated along specific coastal stretches, where wave action sorts the denser mineral grains.
Q57. Match the ore formulas with names:
a. Al₂O₃·2H₂O;
b. MnO₂;
c. Fe₃O₄;
d. HgS.
Names:
i. Magnetite;
ii. Cinnabar;
iii. Carnallite;
iv. Pyrolusite;
v. Bauxite.
[AP Police Constable (Mains), 1 June 2025]
(A) a-ii, b-iii, c-iv, d-v
(B) a-v, b-iv, c-i, d-ii
(C) a-v, b-iv, c-ii, d-iii
(D) a-iii, b-i, c-ii, d-iv
𝐀𝐧𝐬𝐰𝐞𝐫: (B) a-v, b-iv, c-i, d-ii
Explanation: Hydrated aluminium oxide represents bauxite in this conventional ore-formula exercise. MnO₂ is pyrolusite, Fe₃O₄ is magnetite and HgS is cinnabar. Matching chemical compositions with mineral names helps identify the metals extracted from each ore.
Q56. In which of the following districts is the mineral beryl found?
[CGPSC Prelims, 9 February 2025]
(A) Korba
(B) Raigarh
(C) Jashpur
(D) Raipur
𝐀𝐧𝐬𝐰𝐞𝐫: (C) Jashpur
Explanation: Jashpur in Chhattisgarh has reported beryl occurrences, commonly associated with pegmatite formations. Beryl is a beryllium aluminium silicate, Be₃Al₂Si₆O₁₈, and is an important natural source of beryllium used in specialized lightweight alloys.
Q55. Which one among the following oxides has the highest melting point?
[UPSC NDA I (General Ability Test), 21 April 2024]
(A) Na₂O
(B) MgO
(C) Fe₂O₃
(D) CuO
𝐀𝐧𝐬𝐰𝐞𝐫: (B) MgO
Explanation: Magnesium oxide has a very high melting point, approximately 2,850°C, because the electrostatic attraction between Mg²⁺ and O²⁻ ions is strong. It is therefore used as a refractory lining in kilns, furnaces and other high-temperature equipment.
Q54. Which one of the following is primarily responsible for conduction of current in a metal?
[UPSC NDA I (General Ability Test), 21 April 2024]
(A) Bound electrons
(B) Free electrons
(C) Both bound and free electrons
(D) Ions
𝐀𝐧𝐬𝐰𝐞𝐫: (B) Free electrons
Explanation: In metals, some outer electrons are delocalized and can move through the crystal lattice. When an electric field is applied, their net drift constitutes electric current. The metal ions remain largely fixed in their lattice positions.
Q53. The district of Shivamogga, famous for iron ore and manganese minerals, is located in which Indian state?
[SSC CHSL Tier I, 5 July 2024, Shift 3]
(A) Karnataka
(B) Rajasthan
(C) Jharkhand
(D) Maharashtra
𝐀𝐧𝐬𝐰𝐞𝐫: (A) Karnataka
Explanation: Shivamogga is a district of Karnataka, a state with noteworthy iron-ore and manganese resources. Manganese is frequently added to steel to improve its properties and assist in removing oxygen and sulphur during steelmaking.
Q52. Which of the following is a precious mineral?
[SSC MTS, 18 October 2024, Shift 2]
(A) Hematite
(B) Mica
(C) Bauxite
(D) Platinum
𝐀𝐧𝐬𝐰𝐞𝐫: (D) Platinum
Explanation: Platinum is a rare, valuable and corrosion-resistant noble metal. It is used in jewellery, industrial catalysts and vehicle catalytic converters. Hematite is an iron ore, bauxite is an aluminium ore and mica is an industrial silicate mineral.
Q51. Which two properties of metals are exploited to make very thin sheets of silver for decorating sweets?
[SSC MTS, 5 November 2024, Shift 3]
(A) Ductility and lustre
(B) Malleability and sonorousness
(C) Lustre and sonorousness
(D) Malleability and lustre
𝐀𝐧𝐬𝐰𝐞𝐫: (D) Malleability and lustre
Explanation: Malleability permits silver to be hammered into extremely thin sheets without breaking, while metallic lustre provides the reflective decorative finish. Ductility, by contrast, is the ability to draw a metal into wires rather than sheets.
