Question

2
18. The electronic configuration of five elements V, W, X, Y and Z are given below
V-2,8,7 = 17
W-2,8,8 = 18
X-2
Y-2,6 - 8
Z-2,8,2 - 12
Which element belongs to the second period?
1) Which element belongs to the second group?
Which elements belong to the eighteenth group.
iv) Which elements form anions?
y What is the group of element V?
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Answer 1

Answer:

element Y belongs to the second period

element Z belongs to the second group

element W and X belongs to the eighteenth group.

V and Y

17 th group

Answer 2

Answer:

( 1 ) Element 'Y' belongs to the second period.

Explanation:

• Electronic configuration of Y = 2,6
• The period number is determined by the number of shells the element is arranged in.
• As element 'Y' is arranged in only 2 shells,

         K  L  M  N

         2  6  0  0

• Hence, it belongs to period 2.

( 2 ) Element  'Z' belongs to second group.

Explanation:

• Electronic configuration of Z = 2,8,2
• The group number is determined by the number of valence or outmost electrons.
• As element Z has 2 electrons in its outermost shell and is not an octet

          K  L  M  N

          2  8  2   0

• Hence, it belongs to group 2.

( 3 ) Elements 'X' and 'W' belong to the 18th group.

Explanation:

• Electronic configuration of X= 2 and W = 2,8,8
• The group number is determined by the umber of valence electrons present in the outermost shell.
• Elements X and W have completely filled valence shells and are known to be noble gases.

        X=   K  L  M  N          W = K  L  M  N

                2 0  0   0                  2  8  8  0

• All these noble gases are arranged in the 18th group.

( 4 ) Elements 'V' and 'Y' would form anions.

Explanation:

• Non- metallic elements that tend to gain electrons form anions, i.e. negatively charged particles.

• Elements V, electronic configuration = 2,8,7

        and Y, electronic configuration = 2,6 tend to gain electrons.

• Thus they would form anions.

( 5 ) Element 'V' belongs to the 17th group also known as the Halogens group.

Explanation:

• Halogens are the non- metallic elements that tend to gain 1 electron and become stable as noble gases.
• Element V requires only one electron to become stable and attain a noble gas configuration.

        V=  K  L  M  N

              2   8  7   0

• Hence, it belongs to the 17th group.

Hope you got each and every explanation of mine.

Thank You.