Home Subjects JEE Chemistry

JEE Chemistry

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

143 Q 5 Topics Take Test
Advertisement
Difficulty: All Easy Medium Hard 71–80 of 143
Topics in JEE Chemistry
The oxidation state of Mn in KMnO₄ is:
A +5
B +6
C +7
D +4
Correct Answer:  C. +7
EXPLANATION

In KMnO₄, K is +1, O is -2, so Mn is +7. This makes permanganate a strong oxidizing agent.

Take Test
The bond angle in PCl₃ is approximately:
A 120°
B 107°
C 109.5°
D 90°
Correct Answer:  B. 107°
EXPLANATION

PCl₃ has trigonal pyramidal geometry with one lone pair on phosphorus. Bond angle is approximately 107° due to lone pair repulsion.

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

SF₆ has 6 bonding pairs around sulfur with no lone pairs, requiring sp³d² hybridization for octahedral geometry.

Take Test
Which of the following d-block elements has the configuration [Ar]3d¹⁰4s¹?
A Copper
B Zinc
C Nickel
D Cobalt
Correct Answer:  A. Copper
EXPLANATION

Copper has atomic number 29 with configuration [Ar]3d¹⁰4s¹. It exhibits anomalous behavior by having a completely filled d-orbital.

Take Test
The coordination number of Cu²⁺ in CuSO₄·5H₂O is:
A 4
B 6
C 8
D 5
Correct Answer:  B. 6
EXPLANATION

Cu²⁺ is surrounded by 4 water molecules in the coordination sphere and 2 more from the sulfate ion or additional water molecules, giving octahedral geometry with coordination number 6.

Take Test
Which of the following is not a property of noble gases?
A Very low ionization energy
B Zero electron affinity (approximately)
C Inert chemical behavior
D Complete s and p orbital filling
Correct Answer:  A. Very low ionization energy
EXPLANATION

Noble gases have VERY HIGH ionization energies (not low) due to their stable electron configuration. All other options are correct properties of noble gases.

Take Test
Which statement about nitrogen oxides is incorrect?
A NO is colorless gas
B NO₂ is brown gas
C N₂O₄ is blue gas
D N₂O is laughing gas
Correct Answer:  C. N₂O₄ is blue gas
EXPLANATION

N₂O₄ is colorless gas, not blue. NO is colorless, NO₂ is brown/reddish-brown, and N₂O is indeed called laughing gas.

Take Test
Which of the following has the highest electronegativity value?
A Cl
B F
C O
D N
Correct Answer:  B. F
EXPLANATION

Fluorine has the highest electronegativity value (4.0 on Pauling scale) among all elements due to its small size and high nuclear charge.

Take Test
Which of the following oxides is amphoteric?
A Na₂O
B Al₂O₃
C SiO₂
D P₂O₅
Correct Answer:  B. Al₂O₃
EXPLANATION

Al₂O₃ is amphoteric, reacting with both strong acids (forming AlCl₃) and strong bases (forming aluminate ions). Na₂O is basic, SiO₂ is acidic, and P₂O₅ is acidic.

Take Test
Which of the following elements forms the most stable hydride?
A Cl
B F
C Br
D I
Correct Answer:  B. F
EXPLANATION

Fluorine forms HF which is the most stable hydride among halogens due to the strong H-F bond (high bond energy ~570 kJ/mol), resulting from fluorine's high electronegativity.

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