$K_2Cr_2O_7$ on heating with aqueous $NaOH$ gives:

Which of the following exhibits the maximum oxidation state of vanadium?

The number of terminal oxygen atoms present in the product $B$ obtained from the following reaction is $....$
$4FeCr_2O_4 + 8Na_2CO_3 + 7O_2 \rightarrow 8Na_2CrO_4 + 2Fe_2O_3 + 8CO_2$
$2Na_2CrO_4 + 2H^{+} \rightarrow B + H_2O + 2Na^{+}$

The bonds present in the structure of dichromate ion are:

Which of the following is most basic in nature?

When dilute $H_2SO_4$ is added to an aqueous solution of potassium chromate,the yellow color of the solution turns to orange. What does this indicate?