Multiple Choice
Which of the following is the correct electron configuration for calcium (Ca)?
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 correct electron configuration for beryllium (Be)?
A
1s^2 2p^2
B
1s^2 2s^2
C
1s^2 2p^1
D
1s^2 2s^1
Verified step by step guidance1
Step 1: Identify the atomic number of beryllium (Be). The atomic number tells us the number of electrons in a neutral atom. For Be, the atomic number is 4, so it has 4 electrons.
Step 2: Recall the order in which electron orbitals are filled according to the Aufbau principle. Electrons fill orbitals starting from the lowest energy level: 1s, then 2s, then 2p, and so on.
Step 3: Fill the electrons into the orbitals following the order and the Pauli exclusion principle (each orbital can hold a maximum of 2 electrons with opposite spins). For 4 electrons, fill 2 electrons in 1s orbital and then place the remaining 2 electrons in the 2s orbital.
Step 4: Write the electron configuration by indicating the number of electrons in each orbital. Since 2 electrons fill the 1s orbital and 2 electrons fill the 2s orbital, the configuration is $1s^2 2s^2$.
Step 5: Verify that the configuration matches the total number of electrons (4) and follows the correct filling order. This confirms that $1s^2 2s^2$ is the correct electron configuration for beryllium.
Related Videos
Related Practice
The Electron Configuration practice set
Problem sets built by lead tutorsExpert video explanations