A gas that can readily decolorize an acidified KMnO₄ solution is:

1.	SO2	2.	NO2
3.	P2O5	4.	CO2

Which of the following statements is false? 

The ionization potential values of d-block elements as compared to the ionization potential values of f-block elements are:

Which one of the following is a diamagnetic ion?

Which of the following statements is false? 

The reason for lanthanoid contraction is:

1. Negligible screening effect of 'f' orbitals

2. Increasing nuclear charge

3. Decreasing nuclear charge

4. Decreasing screening effect

An element that does not show variable oxidation state is:

A pair among the following that has both coloured ions in the aqueous solution is-
(At. no : Sc =21, Ti = 22, Ni = 28, Cu = 29, Co = 27)

 The increasing order of oxidising power among the following species is:

1. ${{}_{}}^{}$\(\mathrm{VO}_2^{+}<\mathrm{Cr}_2 \mathrm{O}_7^{2-}<\mathrm{MnO}_4^{-}\)   
2. \(\mathrm{VO}_2^{+}<\mathrm{MnO}_4^{-}<\mathrm{Cr}_2 \mathrm{O}_7^{2-}\)  
3. \(\mathrm{Cr}_2 \mathrm{O}_7^{2-}<\mathrm{VO}_2^{+}<\mathrm{MnO}_4^{-}\)
4. \(\mathrm{Cr}_2 \mathrm{O}_7{ }^{2-}<\mathrm{MnO}_4^{-}<\mathrm{VO}_2^{+}\)