The 7th group metals remarks about their general chemical properties and reactivity

3 The 7th group metals remarks about their general chemical properties and reactivity 

Manganese is reactive when pure, it burns in 02 it dissolves in dilute acids. Roughly similar to iron in several physical and chemical properties, but harder, more brittle and less refractory. At elevated temperatures it reacts violently with several non-metals. The Mn11 is the most stable state, readily oxidized in alkaline solutions. The highest oxidation state is VII (corresponding to the total number of 3d and 45 electrons). 

Technetium and rhenium differ markedly from manganese, but they are very similar to each other. They have little cationic chemistry, few compounds in the oxidation state II, more extensive chemistry in the IV and V states. The metals resemble Pt in their appearance (usually, however, they are in the form of a grey powder) they tarnish slowly in moist air, do not react with water. Metal dust is a fire and explosion hazard. 

Element 1 st ionization energy/kJ/mol 2nd ionization energy/kJ/mol 3rd ionization energy/kJ/mol 7th ionization energy/kJ/mol 8th ionization energy/kJ/mol 

Element (allotrope) Crystal Lattice parameters/ Atomic Molar Density/ 

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