Exercise-2

Zinc Oxide, white in colour at room temperature, acquires yellow colour on heating due to:

A complex anion is formed by Osmium (in some oxidation state) with ligands (in proper number, so that the coordination number of osmium becomes six). Which of the following can be its correct $\mathrm{IUPAC}$ name?

All the following complexes show decrease in their weights when placed in a magnetic balance then the group of complexes having tetrahedral geometry is

$\left(\mathrm{I}\right)$ $\mathrm{Ni}(\mathrm{CO}{)}_4$

$\left(\mathrm{II}\right)$ $\mathrm{K}\left[{\mathrm{AgF}}_4\right]$

$\left(\mathrm{III}\right)$ ${\mathrm{Na}}_2\left[\mathrm{Zn}{\left(\mathrm{CN}\right)}_4\right]$

$\left(\mathrm{IV}\right)$${\mathrm{K}}_2\left[{\mathrm{PtCl}}_4\right]$

$\left(\mathrm{V}\right)$ $\left[RhCl{\left({\mathrm{PPh}}_3\right)}_3\right]$

Among ${\mathrm{TiF}}_6^{2-},{\mathrm{CoF}}_6^{3-},{\mathrm{Cu}}_2{\mathrm{Cl}}_2$ and ${\mathrm{NiCl}}_4^{2-}$ the colourless species are:

Which of the following statement(s) are incorrect? 

Consider the following statements:

${\mathrm{S}}_1:$ ${\left[{\mathrm{MnCl}}_6\right]}^{3-},{\left[{\mathrm{FeF}}_6\right]}^{3-}$ and ${\left[{\mathrm{COF}}_6\right]}^{3-}$ are paramagnetic having four, five and four unpaired electrons respectively.

${\mathrm{S}}_2:$ Low value of formation constant of a complex indicates its high thermodynamic stability.
${\mathrm{S}}_3:$ The crystal field splitting ${\mathrm{\Delta }}_0,$ depends upon the field produced by the ligand and charge on the metal ion.

and arrange in the order of true/ false.

Three arrangements are shown for the complex ${\left[\mathrm{Co}\left(\mathrm{en}\right){\left({\mathrm{NH}}_3\right)}_2{\mathrm{Cl}}_2\right]}^{+}.$ Pick up the wrong statement.

Following Sidwick's rule of $\mathrm{EAN}, \mathrm{Co}(\mathrm{CO}{)}_{\mathrm{x}}$ will be: