13
MCQ (Single Correct Answer)
The most commonly used reducing agent is
A
$\mathrm{AlCl}_3$
B
$\mathrm{PbCl}_2$
C
$\mathrm{SnCl}_4$
D
$\mathrm{SnCl}_2$
14
MCQ (Single Correct Answer)
Dry ice is
A
solid $\mathrm{NH}_3$
B
solid $\mathrm{SO}_2$
C
solid $\mathrm{CO}_2$
D
solid $\mathrm{N}_2$
15
MCQ (Single Correct Answer)
Cement, the important building material is a mixture of oxides of several elements. Besides calcium, iron and sulphur, oxides of elements of which of the group $(s)$ are present in the mixture?
A
Group 2
B
Groups 2, 13 and 14
C
Groups 2 and 13
D
Groups 2 and 14
16
MCQ (Multiple Correct Answer)
The reason for small radius of Ga compared to Al is ............ .
A
poor screening effect of $d$ and $f$-orbitals
B
increase in nuclear charge
C
presence of higher orbitals
D
higher atomic number
17
MCQ (Multiple Correct Answer)
The linear shape of $\mathrm{CO}_2$ is due to ............ .
A
$s p^3$ hybridisation of carbon
B
$s p$ hybridisation of carbon
C
$p \pi-p \pi$ bonding between carbon and oxygen
D
$s p^2$ hybridisation of carbon