Answer :
To determine the correct electron configuration for boron, let's analyze the options and understand the electron configurations.
Boron (B) has an atomic number of 5, meaning it has 5 electrons. We need to distribute these electrons according to the energy levels and sublevels.
1. Option: [tex]\(1s^2 2s^3\)[/tex]
- In this configuration, the 2s sublevel is shown to hold 3 electrons. However, the 2s sublevel can hold a maximum of 2 electrons. Therefore, this configuration is incorrect.
2. Option: [tex]\(1s^2 2s^2 3s^1\)[/tex]
- This suggests that after filling the 2s sublevel, an electron is placed in the 3s sublevel. However, after the 2s sublevel, the next electrons should fill the 2p sublevel before moving to the 3s sublevel. Therefore, this configuration is also incorrect.
3. Option: [tex]\(1s^1 2s^2 2p^2\)[/tex]
- Here, the 1s sublevel is shown with only 1 electron, while it can hold up to 2 electrons. In addition, the sum of electrons is 5, but they are not correctly distributed according to increasing energy levels. Therefore, this is not a correct configuration.
4. Option: [tex]\(1s^2 2s^2 2p^1\)[/tex]
- This configuration correctly fills the 1s sublevel first with 2 electrons, then the 2s sublevel with 2 electrons, followed by placing the remaining electron in the 2p sublevel. The sum of electrons is 5, matching the atomic number of boron and follows the correct order of filling sublevels.
Thus, the correct electron configuration for boron is [tex]\(1s^2 2s^2 2p^1\)[/tex]. The right answer is:
[tex]\[ \boxed{4} \][/tex]
Boron (B) has an atomic number of 5, meaning it has 5 electrons. We need to distribute these electrons according to the energy levels and sublevels.
1. Option: [tex]\(1s^2 2s^3\)[/tex]
- In this configuration, the 2s sublevel is shown to hold 3 electrons. However, the 2s sublevel can hold a maximum of 2 electrons. Therefore, this configuration is incorrect.
2. Option: [tex]\(1s^2 2s^2 3s^1\)[/tex]
- This suggests that after filling the 2s sublevel, an electron is placed in the 3s sublevel. However, after the 2s sublevel, the next electrons should fill the 2p sublevel before moving to the 3s sublevel. Therefore, this configuration is also incorrect.
3. Option: [tex]\(1s^1 2s^2 2p^2\)[/tex]
- Here, the 1s sublevel is shown with only 1 electron, while it can hold up to 2 electrons. In addition, the sum of electrons is 5, but they are not correctly distributed according to increasing energy levels. Therefore, this is not a correct configuration.
4. Option: [tex]\(1s^2 2s^2 2p^1\)[/tex]
- This configuration correctly fills the 1s sublevel first with 2 electrons, then the 2s sublevel with 2 electrons, followed by placing the remaining electron in the 2p sublevel. The sum of electrons is 5, matching the atomic number of boron and follows the correct order of filling sublevels.
Thus, the correct electron configuration for boron is [tex]\(1s^2 2s^2 2p^1\)[/tex]. The right answer is:
[tex]\[ \boxed{4} \][/tex]
