객관식
How many valence electrons does an atom of aluminum (Al) possess?
182
views
10. Periodic Properties of the Elements
Valence Electrons of Elements
객관식
Which of the following is the correct number of valence electrons in the element gallium (Ga)?
A
5
B
1
C
7
D
3
검증된 단계별 안내1
Identify the atomic number of gallium (Ga), which is 31. This tells us the total number of electrons in a neutral atom of gallium.
Write the electron configuration of gallium to understand the distribution of electrons in its shells and subshells. The electron configuration is: \$1s^2 2s^2 2p^6 3s^2 3p^6 3d^{10} 4s^2 4p^1$.
Determine the valence electrons by focusing on the electrons in the outermost shell (highest principal quantum number). For gallium, the outermost shell is the 4th shell, which contains \$4s^2$ and \$4p^1$ electrons.
Count the electrons in the outermost shell: \(2\) electrons in the \$4s$ subshell plus \(1\) electron in the \$4p$ subshell, giving a total of \(3\) valence electrons.
Conclude that gallium has 3 valence electrons, which corresponds to the correct answer.
관련 영상
관련 실천
