explain why BF3 is planar while BrF3 is T-shaped.
Answers
Answer:
BF3 is planar and BrF3 has T-shap because of lone pairs are present at Br rather than B.
Explanation:
In BrF 3 molecule out of 7 valencies of bromine 3 are satisfied by fluorine. So there are 2 lone pairs of electron present around the bromine along with 3 bond pairs. So, BrF 3 shows sp3 d hybridization.
Hence, it should show trigonal bipyramidal geometry but it shows T-shape because of 2 lone pairs of electrons.
BF3 shows the the planar geomatery because it has sp2 hybridization and Boron has only 3 valence electrons, so when it bonds with F there will only be 3 electron pairs around the boron atom. Repulsion theory predicts that these three e- pairs should find themselves at the vertices of an equilateral triangle (bond angles of 120 degrees). Thus, BF3 is planar triangular.