Which one of the following is NOT correct about Fe, Cu and Zn, which are in the first row of the transition metals?
A. They all form basic oxides.
B. They all have densities greater than those of Group 1 metals.
C. They are all reactive metals.
D. All of them form {M^{2+}} ions.
E. Only two of them form coloured ions.
All 3 of these elements; Iron, Copper and Zinc are transition metals.
Metal Oxides form Basic Oxides, therefore A is correct.
Transition metals are more dense than Alkali metals; due to their small atomic size and stronger metallic forces in comparison to Group 1 metals. Therefore B is correct.
While Iron and Zinc are relatively reactive, Copper is very unreactive. Therefore C is our answer.
Transition Metals are known for their various oxidation states and ability to form complex ions, therefore D is also correct.
E is also correct, as only Iron and Copper form colored compounds. Iron 2 forming a green color and Iron 3 forming a brownish color. Copper forms a blue color. Zinc does not form colored compounds because of it’s full 3d orbitals.