IIT-JEE 2010 · Paper 2 · Chemistry Q2

ChemistrySingle correct+5 / -2Question 2 of 57

The species having pyramidal shape is

\ce{SO3}

\ce{BrF3}

\ce{SiO3^{2-}}

\ce{OSF2}

Answer and worked solution

Official answer: D

$\ce{SO3}$ : three σ bonds, no lone pair on S: trigonal planar.
$\ce{BrF3}$ : three bonds and two lone pairs: T-shaped.
$\ce{SiO3^{2-}}$ (metasilicate unit): trigonal planar about Si in the formula sense (chains of tetrahedra in reality), not pyramidal.
$\ce{OSF2}$ (thionyl fluoride): S has three σ bonds and one lone pair: pyramidal.

(D)

Topics:VSEPR theory

IIT-JEE 2010 · Paper 2, Chemistry question 2