2
MCQ (Single Correct Answer)
Which of the following is a Lewis acid?
A
$\mathrm{AlCl}_3$
B
$\mathrm{MgCl}_2$
C
$\mathrm{CaCl}_2$
D
$\mathrm{BaCl}_2$
3
MCQ (Single Correct Answer)
The geometry of a complex species can be understood from the knowledge of type of hybridisation of orbitals of central atom. The hybridisation of orbitals of central atom in $\left[\mathrm{B}\left(\mathrm{OH}_4\right)\right]^{-}$and the geometry of the complex are respectively
A
$s p^3$, tetrahedral
B
$s p^3$, square planar
C
$s p^3 d^2$, octahedral
D
$d s p^2$, square planar
4
MCQ (Single Correct Answer)
Which of the following oxides is acidic in nature?
A
$\mathrm{B}_2 \mathrm{O}_3$
B
$\mathrm{Al}_2 \mathrm{O}_3$
C
$\mathrm{Ga}_2 \mathrm{O}_3$
D
$\ln _2 \mathrm{O}_3$
5
MCQ (Single Correct Answer)
The exhibition of highest coordination number depends on the availability of vacant orbitals in the central atom. Which of the following elements is not likely to act as central atom in $M \mathrm{~F}_6^{3-}$ ?
A
B
B
Al
C
Ga
D
In
6
MCQ (Single Correct Answer)
Boric acid is an acid because its molecule
A
contains replaceable $\mathrm{H}^{+}$ion
B
gives up a proton
C
accepts $\mathrm{OH}^{-}$from water releasing proton
D
combines with proton from water molecule