1
MCQ (Single Correct Answer)
Hydrogen resembles halogens in many respects for which several factors are responsible. Of the following factors which one is most important in this respect?
A
Its tendency to lose an electron to form a cation
B
Its tendency to gain a single electron in its valence shell to attain stable electronic configuration
C
Its low negative electron enthalpy value
D
Its small size
2
MCQ (Single Correct Answer)
Why does $\mathrm{H}^{+}$ion always get associated with other atoms or molecules?
A
Ionisation enthalpy of hydrogen resembles that of alkali metals
B
Its reactivity is similar to halogens
C
It resembles both alkali metals and halogens
D
Loss of an electron from hydrogen atom results in a nucleus of very small size as compared to other atoms or ions. Due to small size it cannot exist free
3
MCQ (Single Correct Answer)
Metal hydrides are ionic, covalent or molecular in nature. Among LiH, $\mathrm{NaH}, \mathrm{KH}, \mathrm{RbH}, \mathrm{CsH}$, the correct order of increasing ionic character is
A
$\mathrm{LiH}>\mathrm{NaH}>\mathrm{CsH}>\mathrm{KH}>\mathrm{RbH}$
B
$\mathrm{LiH}<\mathrm{NaH}<\mathrm{KH}<\mathrm{RbH}<\mathrm{CsH}$
C
$\mathrm{RbH}>\mathrm{CsH}>\mathrm{NaH}>\mathrm{KH}>\mathrm{LiH}$
D
$\mathrm{NaH}>\mathrm{CsH}>\mathrm{RbH}>\mathrm{LiH}>\mathrm{KH}$
4
MCQ (Single Correct Answer)
Which of the following hydrides is electron-precise hydride?
A
$\mathrm{B}_2 \mathrm{H}_6$
B
$\mathrm{NH}_3$
C
$\mathrm{H}_2 \mathrm{O}$
D
$\mathrm{CH}_4$
5
MCQ (Single Correct Answer)
Radioactive elements emit $\alpha, \beta$ and $\gamma$ rays and are characterised by their half-lives. The radioactive isotope of hydrogen is
A
protium
B
deuterium
C
tritium
D
hydronium