Fill in the blanks:
$(1)$ Since $V_2O_5$ acts as both an acid and a base,it is an ...... oxide.
$(2)$ The $Cr$ oxide which is basic is ......,and the $Cr$ oxide which is amphoteric is ...... .
$(3)$ The formula of chromite ore is .......... .
$(4)$ The formula of sodium dichromate crystal is .......... .

Among $CrO$,$Cr_2O_3$,and $CrO_3$,the sum of spin-only magnetic moment values of basic and amphoteric oxides is . . . . . . . . $10^{-2} \ BM$ (nearest integer).
(Given atomic number of $Cr$ is $24$)

What is the starting material for the preparation of $KMnO_4$?

Consider the following reactions:
$K_2Cr_2O_7$ $\xrightarrow[-H_2O]{KOH} [A]$ $\xrightarrow[-H_2O]{H_2SO_4} [B] + K_2SO_4$
The products $[A]$ and $[B]$,respectively,are:

Determine the correct $(T)$ and incorrect $(F)$ statements from the following:
$(a)$ The $E^o$ for $MnO_4^- + 8H^+ + 5e^- \to Mn^{2+} + 4H_2O$ is $-1.52 \ V$.
$(b)$ $MnO_4^-$ oxidizes $I^-$ to $I_2$.
$(c)$ The color of $CrO_4^{2-}$ is yellow in the presence of $H^+$.
$(d)$ The color of $CrO_4^{2-}$ is yellow in the presence of $OH^-$.

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: