IS. Read the following and answer my four questions from 19 to 19).
In the following table, eight elements A B C D E RO and (here letters are now the usual symborska
of the elements) or the Modern Periodic Tame with the atomic number of the elemente in parenthe
are given
Groq
Group 2
A
TO
(19)
G)
D(27)
What is the clectronic configuration of F?
() 27
b) 281
(c) 282
(d) 2,8,82
(or) What is the number of valence electrons in the atom of E
(b) 7
c1
(do
(1) What is the number of shells in the atom of F?
(a) two
(b) three
(c) four
(d) one
(iv) The size of the atoms of E, F G and H in decreasing order is
(a) E > F > G > H
(b) H > G > F>E
(c) E > G > F>H
(d) HE > F>G
(1) Out of the three elements B. E and F, which one has the biggest atomic size?
(e) B
(6) E
(c) F
(d) None of these
Answers
Answer:
Electronic configuration
Explanation:
(i) Electronic configuration of F(12) is 2, 8, 2.
(ii) There are 2 valence electrons in the atom of F.
(iii) There are 3 shells in the atom of F.
(iv) The atomic size increases as we go from top to bottom of a Group in the periodic table due to the increment in shells. So the size of atoms in the decreasing order is H > G > F > E.
(v) F has 2 valence electrons. To achieve the octet, it will tend to donate 2 electrons. So it is a metal as metals have the tendency to lose electrons.
(vi) The atomic size increases as we go from top to bottom of a Group in the periodic table due to the increment in shells. The atomic size decreases as we go from left to right of a period. So, among the 3 elements given, B has the biggest atomic size.
Explanation: