Answer:
Ca₂₀ = 1s² 2s² 2p⁶ 3s² 3p⁶ 4s²
Explanation:
The element of group 2A in 4th period is calcium.
Its atomic number is 20.
Its atomic weight is 40.08 amu.
It is third most abundant metal.
It is silvery soft metal.
It react rapidly with water and air.
It is also used as reducing agent.
it is used to make the alloy with copper, aluminium and beryllium.
Its electronic configuration is:
Ca₂₀ = 1s² 2s² 2p⁶ 3s² 3p⁶ 4s²
1s² 2s² 2p⁶ 3s² 3p⁶ are inner electrons.
4s² are valance electrons. Thus it loses two valance electrons to get complete octet.
Abbreviated electronic configuration:
Ca₂₀ = [Ar] 4s²
The periodic table is the arrangement of elements in the form of tables and periods. The configuration of the element in group 2A and fourth period is [tex]\rm 1s^2,2s^2,2p^63s^2,3p^6,4s^2[/tex].
The electronic configuration is defined as the distribution of the electrons in the atom in different shells.
Group 2A is the second group of the periodic table, consisting of alkali earth metals. The fourth period has the elements with 4 shells. The element in group 2A and fourth period is Calcium.
The atomic number of calcium is 20. The electronic configuration of the element is given as:
[tex]\rm 1s^2,2s^2,2p^63s^2,3p^6,4s^2[/tex]
Learn more about electronic configuration, here;
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