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Which element is a transition metal in Group 9 of the periodic table?
Nickel (Ni)
Iron (Fe)
Copper (Cu)
Cobalt (Co)
Cobalt (Co)
Cobalt (Co) is a transition metal located in Group 9 of the periodic table, characterized by its atomic number 27. It belongs to the 3d series of transition metals and exhibits typical metallic properties such as variable oxidation states.
Cobalt (Co) is a transition metal located in Group 9 of the periodic table, characterized by its atomic number 27. It belongs to the 3d series of transition metals and exhibits typical metallic properties such as variable oxidation states.
Think of the periodic table as a large office building; Group 9 is a specific floor where elements like Cobalt, Rhodium, and Iridium occupy desks, all sharing similar 'professional' characteristics like magnetic properties and catalytic behavior.
Co-Rh-Ir (Cobalt, Rhodium, Iridium) helps recall Group 9; try the phrase: 'Co-Rh-Ir, the 9th group wire'.
ZCoтАЛ=27 тАФ Atomic number of Cobalt
Config=[Ar]3d74s2 тАФ Electron configuration of Cobalt
Transition metals are defined by having partially filled d-orbitals in their neutral or common ionic states. Cobalt has an electron configuration of [Ar]3d74s2; the presence of the 3d subshell makes it a transition element, and its group placement is determined by the total number of valence electrons (valence s+d electrons).
Cobalt is a ferromagnetic metal, meaning it is strongly attracted to magnets.
It is a key component of Vitamin B12, also known as cobalamin.
Transition metals are known for their ability to form colored compounds and act as catalysts in chemical reactions.
High thermal stability
Excellent catalytic properties
Cobalt dust can be toxic and cause respiratory issues upon chronic inhalation.
Manufacturing of superalloys for jet engines
Production of lithium-ion battery electrodes
Nickel (Ni) is in Group 10, Iron (Fe) is in Group 8, and Copper (Cu) is in Group 11.
All elements in Group 9 share similar outer electronic configurations ending in ns2(nтИТ1)d7.
D is correct тАФ Cobalt (Co) is the transition metal belonging to Group 9 of the periodic table.
Always verify group numbers by looking at the column position; remember that for transition metals (d-block), the Group number is often the sum of electrons in the outermost s and d subshells.
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