Periodic Table and Periodicity · Chemistry · COMEDK
MCQ (Single Correct Answer)
1
The first electron gain enthalpy of oxygen is $-141 \mathrm{~kJ} \mathrm{~mol}^{-1}$, its second electron gain enthalpy is :
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2
The first ionisation enthalpy of Al in $\mathrm{kJ} \mathrm{mol}^{-1}$ is:
[Given the first ionisation enthalpy of $\mathrm{Na}, \mathrm{Mg}$ and Si in $\mathrm{kJ} \mathrm{mol}^{-1}$ are 497,738 and 787 respectively]
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3
With reference to Pauling's Electronegativity scale, which one of the following options shows the correct order of electronegativity values of elements?
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4
Among the following, which is not according to the property indicated against it?
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5
The correct decreasing order of negative electron gain enthalpy for $$\mathrm{C}, \mathrm{Ca}, \mathrm{Al}, \mathrm{F}$$ and $$\mathrm{O}$$ is
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6
The group number of the element in the periodic table with the electronic configuration $$(\mathrm{n}-1) \mathrm{d}^2 \mathrm{~ns}^2$$. For $$n=4$$ is:
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7
The increasing order of atomic radii of the following group 13 elements is
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8
In the periodic table metals usually used as catalysts belong to
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