What is the Number of Valence Electrons in Cadmium (Cd)?
Cadmium (Cd), a transition metal found in Group 12 of the periodic table, presents a slightly nuanced answer regarding its valence electrons. While a simple glance at the periodic table might suggest two valence electrons, the reality is a bit more complex due to cadmium's electronic configuration.
The Simple Answer: Cadmium typically exhibits two valence electrons.
The More Complex Explanation:
Cadmium's electronic configuration is [Kr] 4d10 5s2. The outermost shell (the 5s subshell) contains two electrons. In many of its compounds and reactions, cadmium loses these two electrons, resulting in a +2 oxidation state. This is why two is often cited as the number of valence electrons.
However, the 4d electrons are relatively close in energy to the 5s electrons. In some less common circumstances, cadmium can exhibit other oxidation states, although +2 is by far the most prevalent. The involvement of the 4d electrons in bonding is less frequent but not entirely impossible, making the simplistic "two valence electrons" a useful rule of thumb but not always entirely accurate.
Why the Complexity?
The behavior of transition metals is more multifaceted than that of main group elements. The energy difference between the (n-1)d and ns orbitals is relatively small, leading to the possibility of multiple oxidation states and variable participation of d electrons in chemical bonding.
People Also Ask (PAA) Questions and Answers:
What is the atomic number of cadmium?
The atomic number of cadmium is 48. This means it has 48 protons and, in a neutral atom, 48 electrons.
What is the electron configuration of cadmium?
The complete electron configuration of cadmium is 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2. However, for understanding valence electrons, the [Kr] 4d10 5s2 notation is sufficient, where [Kr] represents the electron configuration of krypton.
What is the most common oxidation state of cadmium?
The most common and stable oxidation state of cadmium is +2. This arises from the loss of the two 5s electrons.
Is cadmium a transition metal?
Yes, cadmium is a transition metal. Transition metals are characterized by partially filled d orbitals in their atoms or ions.
How many electrons are in the outermost shell of cadmium?
There are two electrons in the outermost shell (5s2) of a cadmium atom.
What are some uses of cadmium?
Cadmium is used in various applications, including nickel-cadmium (NiCd) batteries, pigments, and as a stabilizer in plastics. However, it is important to note that cadmium is a toxic metal and its use is subject to increasing regulation.
This detailed explanation provides a comprehensive understanding of the valence electrons in cadmium, going beyond a simple answer to account for the intricacies of transition metal chemistry. This approach ensures accuracy and caters to a broader understanding of the subject.
