At 298 K, a 1 litre solution containing 10 mmol of $$\mathrm{C{r_2}O_7^{2 - }}$$ and 100 mmol of $$\mathrm{Cr^{3+}}$$ shows a pH of 3.0.

Given : $$\mathrm{C{r_2}O_7^{2 - } \to C{r^{3 + }}\,;\,E^\circ = 1.330}$$V

and $$\mathrm{{{2.303\,RT} \over F} = 0.059}$$ V

The potential for the half cell reaction is $$x\times10^{-3}$$ V. The value of $$x$$ is __________

The d-electronic configuration of $$\mathrm{[CoCl_4]^{2-}}$$ in tetrahedral crystal field in $${e^mt_2^n}$$. Sum of "m" and "number of unpaired electrons" is ___________

If wavelength of the first line of the Paschen series of hydrogen atom is 720 nm, then the wavelength of the second line of this series is _________ nm. (Nearest integer)

Let $$\mathrm{p,q\in\mathbb{R}}$$ and $${\left( {1 - \sqrt 3 i} \right)^{200}} = {2^{199}}(p + iq),i = \sqrt { - 1} $$ then $$\mathrm{p+q+q^2}$$ and $$\mathrm{p-q+q^2}$$ are roots of the equation.