91Ó°ÊÓ

The molecule which has pyramidal shape is: (a) \(\mathrm{SO}_{3}\) (b) \(\mathrm{PCl}_{3}\) (c) \(\mathrm{CO}_{3}^{2}\) (d) \(\mathrm{NO}_{3}^{-}\)

T-type shape is exhibited by the molecule: (a) \(\mathrm{ClF}_{3}\) \(\square\) (b) \(\mathrm{CHCl}_{3}\) (c) \(\mathrm{CCl}_{4}\) \(\square\) (d) \(\mathrm{PCl}_{5}\)

An example of molecule having a three centre bond is: (a) BN (b) \(\mathrm{H}_{3} \mathrm{BO}_{3}\) \(\begin{array}{lll}\text { (c) } \mathrm{NaBH}_{4} & \square \text { (d) } \mathrm{B}_{2} \mathrm{H}_{6}\end{array}\)

The geometry of the molecule with \(25 \% \mathrm{~s}\) -character in hybrid orbital is: (a) plane triangular (b) linear (c) tetrahedral (d) octahedral

Which of the following elements shows the capacity to form hybrid orbitals by using \(s, p\) and \(d\) -atomic orbitals? (a) \(B\) (b) \(C\) (c) \(\mathrm{N}\) (d) \(\underline{S}\)

Molecule showing angle greater than observed in tetrahedral structure is: (a) \(\mathrm{NH}_{3}\) (b) \(\mathrm{Cl}_{2} \mathrm{O}\) (c) \(\mathrm{H}_{2} \mathrm{O}\) (d) \(\mathrm{OF}_{2}\)

The correct order of the \(\mathrm{O}\) - O bond length in \(\mathrm{O}_{2}, \mathrm{H}_{2} \mathrm{O}_{2}\) and \(\mathrm{O}_{3}\) is: (a) \(\mathrm{O}_{3}>\mathrm{H}_{2} \mathrm{O}_{2}>\mathrm{O}_{2}\) (b) \(\mathrm{O}_{2}>\mathrm{H}_{2} \mathrm{O}_{2}>\mathrm{O}_{3}\) (c) \(\mathrm{O}_{2}>\mathrm{O}_{3}>\mathrm{H}_{2} \mathrm{O}_{2}\) (d) \(\mathrm{H}_{2} \mathrm{O}_{2}>\mathrm{O}_{3}>\mathrm{O}_{2}\)

\(\mathrm{BCl}_{3}\) is a planar molecule whereas \(\mathrm{NCl}_{3}\) is pyramidal because: (a) nitrogen atom is smaller than boron atom \(\square\) (b) \(\mathrm{BCl}_{3}\) has no lone pair of electrons whereas \(\mathrm{NCl}_{3}\) has a lone pair of electrons \(\square\) (c) \(\mathrm{N}-\mathrm{Cl}\) bond is more covalent than \(\mathrm{B}-\mathrm{Cl}\) bond \(\square\) (d) \(\mathrm{B}-\mathrm{Cl}\) bond is more polar than \(\mathrm{N}-\mathrm{Cl}\) bond

Which of the following molecules is planar? (a) \(\mathrm{XeF}_{4}\) (b) \(\mathrm{NF}_{3}\) (c) \(\mathrm{SiF}_{4}\) (d) \(\mathrm{SF}_{4}\)

Which one is the correct statement with reference to solubility of \(\mathrm{MgSO}_{4}\) in water? (a) Hydration energy of \(\mathrm{MgSO}_{4}\) is higher in comparison to its lattice energy [ (b) Ionic potential of \(\mathrm{Mg}^{2+}\) is very low \(\square\) (c) \(\mathrm{SO}_{4}^{2-}\) ion mainly contributes towards hydration energy - (d) Sizes of \(\mathrm{Mg}^{2+}\) and \(\mathrm{SO}_{4}^{2-}\) are similar