Chemistry · PYQ NEET UG 2021

In which one of the following arrangements the given sequence is NOT strictly according to the properties indicated against it?

1. \( \mathrm{H}_{2}\mathrm{O} < \mathrm{H}_{2}\mathrm{S} < \mathrm{H}_{2}\mathrm{Se} < \mathrm{H}_{2}\mathrm{Te} \) (Increasing \( \mathrm{pK}_{a} \) values)
2. \( \mathrm{NH}_{3} < \mathrm{PH}_{3} < \mathrm{AsH}_{3} < \mathrm{SbH}_{3} \) (Increasing acidic character)
3. \( \mathrm{CO}_{2} < \mathrm{SiO}_{2} < \mathrm{SnO}_{2} < \mathrm{PbO}_{2} \) (Increasing oxidizing power)
4. \( \mathrm{HF} < \mathrm{HCl} < \mathrm{HBr} < \mathrm{HI} \) (Increasing acidic strength)