Selected MCQ

Current Question
Which spectral line series lies in visible region for hydrogen?
  • A. Lyman
  • B. Balmer
  • C. Paschen
  • D. Brackett
Correct Answer: B
Explanation:
Balmer series transitions produce visible light.
Related Question 1
Which hybridization is linear?
  • A. sp
  • B. sp²
  • C. sp³
  • D. dsp²
Correct Answer: A
Explanation:
sp gives 180° geometry.
Related Question 2
The Heisenberg uncertainty principle implies:
  • A. Exact prediction possible
  • B. Simultaneous measurement limits
  • C. Deterministic motion
  • D. No probability
Correct Answer: B
Explanation:
Certain pairs cannot be measured precisely together.
Related Question 3
Which orbital has highest energy in hydrogen atom?
  • A. 2s
  • B. 2p
  • C. 3s
  • D. All same for given n
Correct Answer: D
Explanation:
Energy depends only on n in hydrogen.
Related Question 4
Which enzyme breaks hydrogen bonds in DNA?
  • A. Ligase
  • B. Helicase
  • C. Polymerase
  • D. Primase
Correct Answer: B
Explanation:
Helicase unwinds DNA strands.
Related Question 5
Which species shows strongest hydrogen bonding?
  • A. NH₃
  • B. H₂O
  • C. HF
  • D. CH₄
Correct Answer: C
Explanation:
HF has highly polar H–F bond and strong intermolecular attraction.