The conversion of pig iron to steel frequently requires the addition of
$(I)$ oxygen or iron oxide
$(II)$ transition elements
$(III)$ inner transition elements
$(IV)$ silica

Iodine is formed when potassium iodide reacts with a solution of

The transition element of $III-B$ group which forms an alum isomorphic with $Al_2(SO_4)_3 \cdot 18H_2O$ is $Sc$. The color of the compound $Sc_2(SO_4)_3 \cdot (NH_4)_2SO_4 \cdot 24H_2O$ is:

$A$ first row transition metal with the highest enthalpy of atomization,upon reaction with oxygen at high temperature,forms oxides of the formula $M_2O_n$ (where $n=3, 4, 5$). The 'spin-only' magnetic moment value of the amphoteric oxide from the above oxides is $......$ $BM$ (nearest integer). (Given atomic number: $Sc: 21, Ti: 22, V: 23, Cr: 24, Mn: 25, Fe: 26, Co: 27, Ni: 28, Cu: 29, Zn: 30$)

Which of the following ions is green in colour?

Consider the following reactions:
$NaCl + K_{2}Cr_{2}O_{7} + H_{2}SO_{4}$ (conc.) $\rightarrow (A) +$ side products
$(A) + NaOH \rightarrow (B) +$ side product
$(B) + H_{2}SO_{4}$ (dilute) $+ H_{2}O_{2} \rightarrow (C) +$ side product
The sum of the total number of atoms in one molecule each of $(A)$,$(B)$,and $(C)$ is: