Which transition metal reacts with steam to produce hydrogen gas?

How would you account for the increasing oxidising power in the series $VO_2^+ < Cr_2O_7^{2-} < MnO_4^-$?

Fill in the blanks:
$(a)$ The only $Mn$ halide compound that shows an oxidation state of $+7$ is ........
$(b)$ The $E^{\ominus}_{M^{II}/M}$ value is maximum negative for ........ in the $3d$ series.
$(c)$ Between $Cr^{2+}$ and $Fe^{2+}$,the stronger reducing agent is ........

Which statement is incorrect?

For which of the following is the $E^{\ominus}(M^{3+} / M^{2+})$ value negative?

Which of the following statements is not correct?