22
MCQ (Multiple Correct Answer)
Which of the following statements are correct?
A
Helium has the highest first ionisation enthalpy in the periodic table
B
Chlorine has less negative electron gain enthalpy than fluorine
C
Mercury and bromine are liquids at room temperature
D
In any period, atomic radius of alkali metal is the highest
23
MCQ (Multiple Correct Answer)
Which of the following sets contain only isoelectronic ions?
A
$\mathrm{Zn}^{2+}, \mathrm{Ca}^{2+}, \mathrm{Ga}^{3+}, \mathrm{AB}^{3+}$
B
$\mathrm{K}^{+}, \mathrm{Ca}^{2+}, \mathrm{Sc}^{3+}, \mathrm{Cl}^{-}$
C
$\mathrm{P}^{3-}, \mathrm{S}^{2-}, \mathrm{Cl}^{-}, \mathrm{K}^{+}$
D
$\mathrm{Ti}^{4+}, \mathrm{Ar}^2, \mathrm{Cr}^{3+}, \mathrm{V}^{5+}$
24
MCQ (Multiple Correct Answer)
In which of the following options order of arrangement does not agree with the variation of property indicated against it?
A
$\mathrm{AP}^{3+}<\mathrm{Mg}^{2+}<\mathrm{Na}^{+}<\mathrm{F}^{-}$(Increasing ionic size)
B
$\mathrm{B}<\mathrm{C}<\mathrm{N}<\mathrm{O}$ ( Increasing first ionisation enthalpy)
C
$\mathrm{I}<\mathrm{Br}<\mathrm{Cl}<\mathrm{F}$ ( Increasing electron gain enthalpy)
D
$\mathrm{Li}<\mathrm{Na}<\mathrm{K}<\mathrm{Rb}$ ( Increasing metallic radius)
25
MCQ (Multiple Correct Answer)
Which of the following have no unit?
A
Electronegativity
B
Electron gain enthalpy
C
Ionisation enthalpy
D
Metallic character
26
MCQ (Multiple Correct Answer)
Ionic radii vary in
A
inverse proportion to the effective nuclear charge
B
inverse proportion to the square of effective nuclear charge
C
direct proportion to the screening effect
D
direct proportion to the square of screening effect