Home Subjects JEE Chemistry Inorganic Chemistry

JEE Chemistry
Inorganic Chemistry

Chemistry questions for JEE Main — Physical, Organic, Inorganic Chemistry.

33 Q 5 Topics Take Test
Advertisement
Difficulty: All Easy Medium Hard 1–10 of 33
Topics in JEE Chemistry
In the extraction of iron from its ore using a blast furnace, the temperature at the bottom of the furnace reaches approximately 1900°C. At this temperature, which compound primarily acts as the reducing agent?
A Carbon dioxide (CO₂)
B Carbon monoxide (CO)
C Solid carbon (Coke)
D Limestone (CaCO₃)
Correct Answer:  B. Carbon monoxide (CO)
EXPLANATION

At high temperatures in the blast furnace, carbon monoxide (CO) is the primary reducing agent that converts iron oxides to metallic iron. Although coke produces CO, the actual reduction occurs through CO: Fe₂O₃ + 3CO → 2Fe + 3CO₂. This is thermodynamically favorable at furnace temperatures.

Take Test
In the preparation of oxygen by thermal decomposition of KClO₃, the catalyst used is:
A MnO₂
B Pt
C Fe₂O₃
D CuO
Correct Answer:  A. MnO₂
EXPLANATION

MnO₂ is the standard catalyst for KClO₃ decomposition, significantly lowering the decomposition temperature from ~400°C to ~240°C. It acts as a heterogeneous catalyst.

Take Test
Which element shows variable oxidation states primarily due to incomplete d-orbitals?
A Zinc
B Copper
C Manganese
D Calcium
Correct Answer:  C. Manganese
EXPLANATION

Transition metals like Mn show multiple oxidation states (+2, +3, +4, +6, +7) due to incomplete d-orbitals. Zn shows only +2, Cu shows +1 and +2.

Take Test
The oxidation state of bromine in KBrO₄ is:
A +5
B +7
C +3
D +6
Correct Answer:  B. +7
EXPLANATION

In KBrO₄, K is +1 and each O is -2. Therefore: 1 + x + 4(-2) = 0, giving x = +7. Bromine achieves its maximum oxidation state in this perbromate ion.

Take Test
In the contact process for H₂SO₄ manufacture, the catalyst used is:
A Iron
B Vanadium pentoxide
C Platinum
D Copper oxide
Correct Answer:  B. Vanadium pentoxide
EXPLANATION

V₂O₅ is the standard catalyst used in the oxidation of SO₂ to SO₃. It provides excellent activity and selectivity at 400-450°C operational temperature.

Take Test
The aqueous solution of which salt is most acidic due to hydrolysis?
A NaCl
B FeCl₃
C NH₄Cl
D Na₂CO₃
Correct Answer:  B. FeCl₃
EXPLANATION

FeCl₃ undergoes significant hydrolysis: Fe³⁺ + H₂O ⇌ Fe(OH)²⁺ + H⁺. Fe³⁺ is a strong Lewis acid causing extensive hydrolysis and acidic solution.

Take Test
The hybridization of sulphur in SF₆ molecule is:
A sp³
B sp³d
C sp³d²
D d²sp³
Correct Answer:  C. sp³d²
EXPLANATION

SF₆ has 6 fluorine atoms bonded to sulphur with octahedral geometry. The hybridization is sp³d² involving d-orbitals from the third shell.

Take Test
In the extraction of iron from haematite using blast furnace, the reducing agent is primarily:
A Carbon monoxide
B Carbon dioxide
C Coke
D Limestone
Correct Answer:  A. Carbon monoxide
EXPLANATION

CO produced in the blast furnace acts as the primary reducing agent for Fe₂O₃. Although coke is fed, CO generated from coke combustion performs the actual reduction.

Take Test
The coordination number of Co in [Co(NH₃)₆]³⁺ complex is:
A 3
B 4
C 6
D 8
Correct Answer:  C. 6
EXPLANATION

Coordination number is the number of ligands bonded to the central metal. Six NH₃ molecules surround Co³⁺, giving coordination number 6.

Take Test
Which of the following noble gases has the lowest ionization energy?
A Helium
B Neon
C Argon
D Xenon
Correct Answer:  D. Xenon
EXPLANATION

Ionization energy decreases down a group. Xenon (54 electrons) has the largest atomic radius and lowest ionization energy among noble gases listed.

Take Test
IGET
iget AI
Online · Ask anything about exams
Hi! 👋 I'm your iget AI assistant.

Ask me anything about exam prep, MCQ solutions, study tips, or strategies! 🎯
UPSC strategy SSC CGL syllabus Improve aptitude NEET Biology tips