Unisciti a migliaia di studenti che si affidano a noi per superare al meglio i loro esami!
Scelta multipla
How many valence electrons does a neutral magnesium atom have?
A
1
B
6
C
8
D
2
0 Commenti
Guida verificata passo dopo passo
1
Identify the element in question, which is magnesium (Mg).
Determine the atomic number of magnesium, which is 12, meaning it has 12 protons and, in a neutral atom, 12 electrons.
Recall that valence electrons are the electrons in the outermost shell (energy level) of an atom.
Write the electron configuration of magnesium: \$1s^2 2s^2 2p^6 3s^2$.
From the electron configuration, observe that the outermost shell (the third shell) has 2 electrons in the 3s subshell, so magnesium has 2 valence electrons.