The number of $\mathrm{p\pi }-\mathrm{d\pi }$ 'pi' bonds present in XeO₃ and XeO₄ molecules, respectively are

• 3,4

• 4,2

• 2,3

• 3,2

Which one of the following sets correctly represents the increase in the paramagnetic property of the ions?

• Cu²⁺ > V ²⁺ > Cr²⁺ > Mn²⁺

• Cu²⁺ < Cr²⁺  < V ²⁺ < Mn²⁺

• Cu²⁺ < V ²⁺ < Cr²⁺ < Mn²⁺

• V ²⁺ < Cu²⁺  < Cr²⁺ < Mn²⁺

The type of bonds present in sulphuric anhydride are

• $3\mathrm{\sigma } \mathrm{and} \mathrm{three} \mathrm{p\pi }-\mathrm{p\pi }$

• $3\mathrm{\sigma }, \mathrm{one} \mathrm{p\pi }-\mathrm{p\pi } \mathrm{and} \mathrm{two} \mathrm{p\pi }-\mathrm{p\pi }$

• $2\mathrm{\sigma } \mathrm{and} \mathrm{three} \mathrm{p\pi }-\mathrm{d\pi }$

• $2\mathrm{\sigma } \mathrm{and} \mathrm{two} \mathrm{p\pi }-\mathrm{d\pi }$

24.

Which pair of oxyacids of phosphorus contains 'P - H' bonds?

• H₃PO₄, H₃PO₃

• H₃PO₅, H₄P₂O₇

• H₃PO₃, H₃PO₂

• H₃PO₂, HPO₃

Aluminium reacts with NaOH and forms compound 'X'. If the coordination number of aluminium in 'X' is 6, the correct formula of X is

• [Al(H₂O)₄(OH)₂]⁺

• [Al(H₂O)₃(OH)₃]

• [Al(H₂O)₂(OH)₄]^-

• [Al(H₂O)₆](OH)₃

During the depression in freezing point experiment, an equilibrium is established between the molecules of

• liquid solvent and solid solvent

• liquid solute and solid solvent

• liquid solute and solid solute

• liquid solvent and solid solute

Which one of the following is most effective in causing the coagulation of an As₂S₃ sol?

• KCl

• AlCl₃

• MgSO₄

• K₃Fe(CN)₆

$$\begin{gathered} \mathrm{For} \mathrm{the} \mathrm{following} \mathrm{cell} \mathrm{reaction}, \\ \mathrm{Ag}| {\mathrm{Ag}}^{+}| \mathrm{AgCl}| {\mathrm{Cl}}^{⊝}| {\mathrm{Cl}}_2, \mathrm{Pt} \\ ∆{\mathrm{G}}_{\mathrm{f}}^{°}\left(\mathrm{AgCl}\right)= -109 \mathrm{kJ}/\mathrm{mol} \\ ∆{\mathrm{G}}_{\mathrm{f}}^{°}\left({\mathrm{Cl}}^{⊝}\right)= -129 \mathrm{kJ}/\mathrm{mol} \\ ∆{\mathrm{G}}_{\mathrm{f}}^{°}\left({\mathrm{Ag}}^{+}\right)= 78 \mathrm{kJ}/\mathrm{mo}/ \end{gathered}$$

E$°$ of the cell is

• - 0.60 V

• 0.60 V

• 6.0 V

• None of these

At 25$°$C, the molar conductances at infinite dilution for the strong electrolytes NaOH, NaCl and BaCl₂ are 248 $\times$10^-4, 126 x 10^-4 and 280 x 10^-4 Sm² mol^-1 respectively, ${\mathrm{\lambda }}_{\mathrm{m}}^{\infty }$  Ba(OH)₂ in Sm² mol^-1 is

• 52.4 $\times$ 10^-4

• 524 $\times {10}^{-4}$

• 402 $\times {10}^{-4}$

• 262 $\times {10}^{-4}$

For a first order reaction at 27$°$C, the ratio of time required for 75% completion to 25% completion of reaction is

• 3.0

• 2.303

• 4.8

• 0.477