Identify the incorrect statement.
(1) ``\ce{Cr^{2+}(d^4)}`` is a stronger reducing agent than
``\ce{Fe2+(d^6)}`` in water.
(2) The transition metals and their compounds
are known for their catalytic activity due to
their ability to adopt multiple oxidation
states and to form complexes.
(3) Interstitial compounds are those that are
formed when small atoms like H, C or N
are trapped inside the crystal lattices of
metals.
(4) The oxidation states of chromium in
``\ce{CrO4^{2-} }`` and ``\ce{Cr2O7^{2-} }``
are not the same.