Q. In which one of the following arrangements the given sequence is not strictly according to the properties indicated against it?
A) $H_2O < H_2S < H_2Se < H_2Te$ : Increasing $pK_a$ values
B) $NH_3 < PH_3 < AsH_3 < SbH_3$ : Increasing acidic character
C) $CO_2 < SiO_2 < SnO_2 < PbO_2$ : Increasing oxidizing power
D) HF < HCl < HBr < HI : Increasing acidic strength
Explanation
[Solution] Acid strength increases from $H_2O$ to $H_2Te$, so their $pK_a$ values decrease, not increase. Answer (1).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.