How many total valence electrons are present in a neutral manganese (Mn) atom?

• A. 8
• B. 5
• C. 7
• D. 2

Answer: (B)

Verified step by step guidance

1. Identify the electron configuration of a neutral manganese (Mn) atom. Manganese has an atomic number of 25, so it has 25 electrons.
2. Write the electron configuration for Mn: \$1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^5$.
3. Determine which electrons are considered valence electrons. For transition metals like Mn, valence electrons include those in the outermost s and d orbitals.
4. Count the electrons in the 4s and 3d orbitals: \$4s^2\( and \)3d^5\(, which gives a total of \)2 + 5 = 7$ valence electrons.
5. Conclude that a neutral manganese atom has 7 valence electrons.