Draw the lewis structure for BSF
The correct answer and explanation is :
To draw the Lewis structure of BSF (boron monofluoride sulfide), we need to follow a systematic process. BSF consists of boron (B), sulfur (S), and fluorine (F) atoms. Here’s the step-by-step procedure for drawing the Lewis structure of BSF:
Step-by-Step Process:
- Count the Total Number of Valence Electrons:
- Boron (B) is in group 13 of the periodic table, so it has 3 valence electrons.
- Fluorine (F) is in group 17, so each fluorine atom has 7 valence electrons. Since there is one fluorine atom, it contributes 7 electrons.
- Sulfur (S) is in group 16, so it has 6 valence electrons. Total valence electrons = 3 (B) + 7 (F) + 6 (S) = 16 valence electrons.
- Determine the Central Atom:
- Boron (B) will be the central atom since it is less electronegative than sulfur (S) and fluorine (F).
- Place the Atoms and Connect Them with Bonds:
- Place boron (B) in the center, with fluorine (F) and sulfur (S) surrounding it.
- Initially, draw single bonds between boron and fluorine, and boron and sulfur. A single bond consists of 2 electrons.
- Distribute Remaining Electrons:
- After forming the bonds, you have 16 total valence electrons. You’ve used 2 electrons for each of the B-F and B-S bonds (4 electrons total).
- Now, place the remaining electrons as lone pairs on the fluorine and sulfur atoms.
- Fluorine will take 3 lone pairs, and sulfur will take 2 lone pairs to complete their octets.
- Check for Octet Rule:
- Boron in this case can be stable with only 6 electrons around it, which is acceptable because boron is an exception to the octet rule and typically forms compounds with fewer than 8 electrons.
Final Structure:
The structure consists of:
- A B-F single bond.
- A B-S single bond.
- Fluorine with 3 lone pairs of electrons.
- Sulfur with 2 lone pairs of electrons.
- Boron with no lone pairs and only 6 electrons around it.
This gives a stable Lewis structure for BSF.
Explanation:
In BSF, the bonding and electron distribution adhere to the general principles of Lewis structures. The fluorine atom is highly electronegative and thus completes its octet by holding lone pairs. Sulfur can accommodate more electrons and completes its octet as well. Boron, being electron-deficient, does not complete an octet but remains stable with only 6 electrons around it, which is common in boron compounds.