FeCr₂O₄ (chromite) is converted to Cr by following steps :

$\text{Chromite}\stackrel{\text{I}}{\to }{\text{NaCrO}}_4\stackrel{\text{II}}{\to }{\text{Cr}}_2{\text{O}}_3\stackrel{\text{III}}{\to }\text{Cr}$

Reagents in I, II and II step might be :

Which of the following options are correct for the reaction?

$2{\left[\mathrm{Au}(\mathrm{CN}{)}_2\right]}^{-}\left(\mathrm{aq}\right)+\mathrm{Zn}\left(\mathrm{s}\right)\to 2\mathrm{Au}\left(\mathrm{s}\right)+{\left[\mathrm{Zn}(\mathrm{CN}{)}_4\right]}^{2-}\left(\mathrm{aq}\right)$

A. Redox reaction

B. Displacement reaction

C. Decomposition reaction

D. Combination reaction

Choose the correct answer from the options given below:

Statement I: Leaching of gold with cyanide ion in absence of air / ${\mathrm{O}}_2$ leads to cyano complex of $\mathrm{Au}$(III).

Statement II: Zinc is oxidized during the displacement reaction carried out for gold extraction.

In the light of the above statements, choose the correct answer from the options given below.

Match List I with List II : (Both having metallurgical terms)

Choose the correct answer from the options given
below:

Among the following, the main reactions occurring in blast furnace during extraction of iron from haematite are:

(i) ${\mathrm{Fe}}_2{\mathrm{O}}_3+3\mathrm{CO}⟶2\mathrm{Fe}+3{\mathrm{CO}}_2$

(ii) $\mathrm{FeO}+{\mathrm{SiO}}_2⟶{\mathrm{FeSiO}}_3$

(iii) ${\mathrm{Fe}}_2{\mathrm{O}}_3+3\mathrm{C}⟶2\mathrm{Fe}+3\mathrm{CO}$

(iv) $\mathrm{CaO}+{\mathrm{SiO}}_2⟶{\mathrm{CaSiO}}_3$