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The electronic configuration of an element is 1s2 2s2 2p6 3s2 3p3 . The atomic number of the element which is just below the above element in the periodic table is

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Important Questions on Classification of Elements and Periodicity in Properties

EASY
The electronic configurations of Eu (Atomic no. 63), Gd (Atomic no. 64) and Tb (Atomic no. 65) are:
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The last element of the p- block in 6th period is represented by the outermost electronic configuration:
MEDIUM
To which group of the periodic table does an element having electronic configuration [Ar]3d54 s2 belong?
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The 71st electron of an element X with an atomic number of 71 enters the orbital:
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Among the given configurations, identify the element which doesn't belong to the same family as the others?
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The electronic configurations of bivalent europium and trivalent cerium are:
(atomic number: Xe=54 , Ce=58 , Eu=63)
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The element with outer electronic configuration (n-1)d2ns2, where n=4, would belong to
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Element "E" belongs to the period 4 and group 16 of the periodic table. The valence shell electron configuration of the element, which is just above "E" in the group is
EASY

Match the element in column I with that in column II.

  Column-I   Column-II
(a) Copper (p) Non-metal
(b) Fluorine (q) Transition metal
(c) Silicon (r) Lanthanoid
(d) Cerium (s) Metalloid

Identify the correct match :

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Consider the following radioactive decays

I. U92-α90Th and

II. 90Th-αRa88

In which case group of parent and daughter elements remains unchanged.

EASY

The correct match among the following is

(a) Lithium, Sodium, Potassium            (i) Alkaline earth metals
(b) Beryllium, Magnesium, Calcium      (ii) Semi-metals
(c) Oxygen, Sulphur, Selenium             (iii) Alkali metaIs
(d) Silicon, Germanium, Arsenic           (iv) Chalcogens

EASY
The element Z=114 has been discovered recently. It will belong to which of the following family/group and electronic configuration?