Number of ambidentate ligands in a representative metal complex $$\left[\mathrm{M}(\mathrm{en})(\mathrm{SCN})_{4}\right]$$ is ___________.

[en = ethylenediamine]

If 5 moles of $$\mathrm{BaCl}_{2}$$ is mixed with 2 moles of $$\mathrm{Na}_{3} \mathrm{PO}_{4}$$, the maximum number of moles of $$\mathrm{Ba}_{3}\left(\mathrm{PO}_{4}\right)_{2}$$ formed is ___________ (Nearest integer)

In ammonium - phosphomolybdate, the oxidation state of Mo is + ___________

For the adsorption of hydrogen on platinum, the activation energy is $$30 ~\mathrm{k} ~\mathrm{J} \mathrm{mol}^{-1}$$ and for the adsorption of hydrogen on nickel, the activation energy is $$41.4 ~\mathrm{k} ~\mathrm{J} \mathrm{mol}^{-1}$$. The logarithm of the ratio of the rates of chemisorption on equal areas of the metals at $$300 \mathrm{~K}$$ is __________ (Nearest integer)

Given: $$\ln 10=2.3$$

$$\mathrm{R}=8.3 \mathrm{~J} \mathrm{~K}^{-1} \mathrm{~mol}^{-1}$$