Question

Which one of the following statements is true about the SF4 and PF5 molecules

1. both molecules are polar
2. SF4 is nonpolar while PF5 is polar
3. both molecules have lone pairs on the central atom
4. SF4 has an octahedral electron domain geometry while PF5 is trigonal bipyramidal
5. both molecules have bond angles of 120

Answer 1

The true statement is that SF4 is polar while PF5 is nonpolar, due to SF4's seesaw shape and one lone pair on the central atom, compared to the trigonal bipyramidal and highly symmetric shape of PF5. So option (2) is correct.

Step-by-step explanation:

The true statement about the SF4 and PF5 molecules is that SF4 is polar while PF5 is nonpolar. SF4 has a seesaw molecular geometry due to one lone pair on the sulfur atom, making its shape less symmetric and therefore polar. In contrast, PF5 has a trigonal bipyramidal shape with no lone pairs on the central phosphorus atom, giving it high symmetry and making it nonpolar. Additionally, the bond angles in these molecules are not the same; PF5 has bond angles of 120 degrees and 90 degrees, while the bond angles in SF4 deviate from the ideal due to the presence of the lone pair.