Class 12th

Which of the following statements is correct?

The IUPAC name of the complex is $\left[\mathrm{P}\mathrm{t}{\left({\mathrm{N}\mathrm{H}}_3\right)}_2\mathrm{C}\mathrm{l}\left({\mathrm{N}\mathrm{H}}_2{\mathrm{C}\mathrm{H}}_3\right)\right]\mathrm{C}\mathrm{l}$ $\left[{\left({}_{}\right)}_{}\left({}_{}{}_{}\right)\right]$ is

In the following reaction sequence

The theory that can completely/properly explain the nature of bonding in $\left[\mathrm{N}\mathrm{i}(\mathrm{C}\mathrm{O}{)}_4\right]$ $\left[{}_{}\right]$ is

The purest form of commercial iron is

For the reaction

$2{\mathrm{H}}_2\left(\mathrm{g}\right)+2\mathrm{N}\mathrm{O}\left(\mathrm{g}\right)?{\mathrm{N}}_2\left(\mathrm{g}\right)+2{\mathrm{H}}_2\mathrm{O}$ , the observed rate expression is, rate = ${\mathrm{k}}_{\mathrm{f}}[\mathrm{N}\mathrm{O}{]}^2\left[{\mathrm{H}}_2\right]$ . The rate expression for the reverse reaction is:

Three charged particles $A,B$ $$ and $C$ $$ with charges $-4q,2q$ $$ and $$ $-2q$  are present on the circumference of a circle of radius $d$ $$ . The charged particles $A,C$ $$ and centre $O$ $$ of the circle formed an equilateral triangle as shown in figure. Electric field at $\mathrm{O}$ $$ along $\mathrm{x}$ $$ -direction is:

The atomic radius of $\mathrm{A}\mathrm{g}$ $$ is closest to

At ${}^{}$ ${35}^{?}\mathrm{C}$ , the vapour pressure of ${\mathrm{C}\mathrm{S}}_2$ ${}_{}$ is $$ $512\mathrm{m}\mathrm{m}$ of $\mathrm{H}\mathrm{g}$ $$ and that of acetone is $344\mathrm{m}\mathrm{m}$ $$ of $\mathrm{H}\mathrm{g}$ $$ . A solution of ${\mathrm{C}\mathrm{S}}_2$ ${}_{}$ in acetone has a total vapour pressure of $600\mathrm{m}\mathrm{m}$ $$ of $\mathrm{H}\mathrm{g}$ $$ . The false statement among the following is

The refining method used when the metal and the impurities have low and high melting temperatures, respectively is