Question

the atomic number of manganese (mn) is 25. whats the electron configuration for manganese?
a) ne 3d⁷
b) ne 4s² 3p⁵
c) ar 3d⁵ 4s²
d) ar 3s⁵ 4p²
question 17 (5 points)
which of the following statements about metal elements is correct?
a) a metal atom can take an electron from a non - metal atom.
b) metal elements are always heavier than non - metal elements.
c) metals tend to easily lose their valence electrons.

Explanation:

Step1: Determine the electron configuration of Mn

The atomic number of Mn is 25. Argon (Ar) has an atomic number of 18. So, we need to account for \(25 - 18=7\) more electrons.
The \(3d\) sub - shell can hold up to 10 electrons and the \(4s\) sub - shell can hold up to 2 electrons. According to the Aufbau principle, electrons fill the \(4s\) sub - shell before the \(3d\) sub - shell.
The electron configuration of Mn is \([Ar]3d^{5}4s^{2}\)

Step2: Analyze the statement about metal elements

• Option A: Metal atoms tend to lose electrons, while non - metal atoms tend to gain electrons. So, a metal atom does not take an electron from a non - metal atom.
• Option B: Metal elements are not always heavier than non - metal elements. For example, lithium (a metal) has a relatively low atomic mass compared to some non - metals like iodine.
• Option C: Metals have low ionization energies, which means they tend to easily lose their valence electrons.

Answer:

For the electron - configuration question: C. \([Ar]3d^{5}4s^{2}\)
For the metal - element statement question: C. Metals tend to easily lose their valence electrons.