Multiple Choice
Which element has the following ground-state electron configuration: [Kr] 5s2 4d10 5p3?
3
views
10. Periodic Properties of the Elements
The Electron Configuration
Struggling with General Chemistry?
Join thousands of students who trust us to help them ace their exams!Watch the first videoMultiple Choice
Which of the following is the electron configuration of the Ga^{3+} ion?
A
1s^2 2s^2 2p^6 3s^2 3p^6 3d^{10}
B
1s^2 2s^2 2p^6 3s^2 3p^6 3d^{10} 4s^2 4p^1
C
1s^2 2s^2 2p^6 3s^2 3p^6 3d^{10} 4s^2 4p^3
D
1s^2 2s^2 2p^6 3s^2 3p^6 3d^{10} 4s^2
Verified step by step guidance1
Identify the atomic number of gallium (Ga), which is 31. This tells us that a neutral Ga atom has 31 electrons.
Write the electron configuration for the neutral Ga atom by filling orbitals in order of increasing energy: $1s^2 2s^2 2p^6 3s^2 3p^6 3d^{10} 4s^2 4p^1$.
Since the ion is Ga$^{3+}$, it means the atom has lost 3 electrons. Remove electrons starting from the highest energy level orbitals, which are the 4p and 4s orbitals.
Remove 1 electron from the $4p^1$ orbital and 2 electrons from the $4s^2$ orbital to account for the 3+ charge, leaving the configuration without any electrons in the 4s or 4p orbitals.
The resulting electron configuration for Ga$^{3+}$ is $1s^2 2s^2 2p^6 3s^2 3p^6 3d^{10}$, which corresponds to the electron configuration of the ion.
Related Videos
Related Practice
The Electron Configuration practice set
Problem sets built by lead tutorsExpert video explanations