How are transition metals and their oxides used in industrial processes?

Which of these statements is not true?

The highest oxidation state of manganese in fluorides is $+4$ $(MnF_4)$, but the highest oxidation state in oxides is $+7$ $(Mn_2O_7)$, because

Assertion : Transition metals are good catalysts.
Reason : $V_2O_5$ or $Pt$ is used in the preparation of $H_2SO_4$ by contact process.

Ferrous sulphate on heating gives

Write the chemical reactions of lanthanoids $(Ln)$ with the following:
$(1)$ With acid:
$2Ln + 6HCl \rightarrow 2LnCl_3 + 3H_2$
$(2)$ With halogens ($X_2$,where $X = F, Cl, Br, I$):
$2Ln + 3X_2 \rightarrow 2LnX_3$