6
MCQ (Single Correct Answer)
The statement that is not correct for periodic classification of elements is
A
The properties of elements are periodic function of their atomic numbers
B
Non-metallic elements are less in number than metallic elements
C
For transition elements, the $3 d$-orbitals are filled with electrons after $3 p$-orbitals and before $4 s$-orbitals
D
The first ionisation enthalpies of elements generally increase with increase in atomic number as we go along a period
7
MCQ (Single Correct Answer)
Among halogens, the correct order of amount of energy released in electron gain (electron gain enthalpy) is
A
$\mathrm{F}>\mathrm{Cl}>\mathrm{Br}>\mathrm{I}$
B
$\mathrm{F}<\mathrm{Cl}<\mathrm{Br}<\mathrm{I}$
C
$\mathrm{F}<\mathrm{Cl}>\mathrm{Br}\rangle \mathrm{I}$
D
$\mathrm{F}<\mathrm{Cl}<\mathrm{Br}<\mathrm{I}$
8
MCQ (Single Correct Answer)
The period number in the long form of the periodic table is equal to
A
magnetic quantum number of any element of the period
B
atomic number of any element of the period
C
maximum principal quantum number of any element of the period
D
maximum azimuthal quantum number of any element of the period
9
MCQ (Single Correct Answer)
The elements in which electrons are progressively filled in $4 f$-orbital are called
A
actinoids
B
transition elements
C
lanthanoids
D
halogens
10
MCQ (Single Correct Answer)
Which of the following is the correct order of size of the given species
A
I $>\mathrm{I}^{-}>\mathrm{I}^{+}$
B
$\mathrm{I}^{+}>\mathrm{I}^{-}>\mathrm{I}$
C
$\mathrm{I}>\mathrm{I}^{+}>\mathrm{I}^{-}$
D
$\mathrm{I}^{-}>\mathrm{I}>\mathrm{I}^{+}$