Question

how many lone pair(s) of electrons are around se in sef4?

Explanation:

Step1: Calculate the number of valence electrons of Se

Selenium (Se) is in Group 16 of the periodic table, so it has 6 valence electrons.

Step2: Calculate the number of bonding pairs

In \(SeF_4\), Se forms 4 single bonds with F atoms. Each single bond is a bonding pair of electrons. So there are 4 bonding pairs.

Step3: Use the formula for lone pairs

The formula for the number of lone pairs (\(L\)) around a central atom is \(L=\frac{V - B}{2}\), where \(V\) is the number of valence electrons of the central atom and \(B\) is the number of bonding pairs.
Substitute \(V = 6\) and \(B=4\) into the formula: \(L=\frac{6 - 4}{2}=1\)

Answer:

\(1\)