a)what is the name and molecular formula of the reagent responsible for the formation of the nickel complex ions?
b)What is the color of this complexation?
see other post. I can't answer because I don't know what you used in the lab.
http://www.youtube.com/watch?v=hDt2OUnOcug&feature=player_embedded
What would you need to know?
To determine the name and molecular formula of the reagent responsible for the formation of nickel complex ions, as well as the color of the complexation, we need to consider the nature of nickel and its common oxidation states.
a) Nickel forms various complex ions depending on its oxidation state. One of the commonly encountered complex ions is [Ni(H2O)6]2+ (hexaaquanickel(II) ion). This complex ion is formed by the reaction of nickel(II) salts, such as nickel(II) chloride (NiCl2), with water (H2O).
The molecular formula for [Ni(H2O)6]2+ is Ni(H2O)6Cl2. The chloride ions, Cl-, may also be present depending on the source of the nickel salt used.
b) The hexaaquanickel(II) ion, [Ni(H2O)6]2+, exhibits a light green color. This color arises due to the interaction of light with the electrons present in the complex ion.
In summary, the reagent responsible for the formation of nickel complex ions, specifically the hexaaquanickel(II) ion, is a nickel(II) salt (such as nickel(II) chloride) reacting with water. The resulting complex ion, [Ni(H2O)6]2+, appears light green in color.