Question

Choose one of the transition or inner transition metals from the periodic table. (I choose Titanium) Using Chapter 23 of Chemistry, The Molecular Nature of Matter and Change, and Internet resources, discuss why your transition metal and their compounds display a variety of color. Be sure to include in your discussion, important oxidation states, the electron configuration and how the d-electrons are involved. How can you include the electromagnetic spectrum and the nature of light into your discussion? How is energy and wavelength related? Use your knowledge of the emission and absorption of light in your discussion. Remember to site your sources in APA style.

Answer 1

Titanium (Ti) has an atomic number 22 and electronic configuration 1s²2s²2p⁶3s²3p⁶3d²4s². It has partially filled d orbitals. The absorption of energy or photon results in the excitation of electron from lower energy d-orbital to a higher energy d-orbital. Such absorption corresponds to the visible region. Although, the visible light appears white, it is made up of different colors viz., red, yellow, blue, orange, green, indigo and violet. When a wavelength associated to visible spectrum of electromagnetic spectrum is absorbed, we see the colour corresponding to the wavelengths of light that are transmitted.
Energy and wavelength are inversely proportional and related to each other as per the Planck-Einstein’s formula

From the given relationship, the higher energy will correspond to the shorter wavelength. This means that the short wavelengths are more energetic.

Further, The electrons are removed from 4s orbitals first and then from 3d because 3d orbital is less in energy than the 4s orbital.Since, it can loose different numbers of '3d' electrons, Titanium exhibits oxidation states of +2, +3 and +4.