Question

plz anybody answer this questions its urgent.....



11. A,B and C are three elements having their atomic number equal to 2,10 and 5 respectively.
(i) Which of these elements belong to the same period?
(ii) Which of these elements belong to the same group?

12. How do the following properties vary in the 3rd period :
(i) Atomic size
(ii) Metallic charcater
(iii) Ionisation energy.

13. The electronic configuration of three elements A, B and C
are 2,8,8; 2,2,6 and 2,8,2 respectively. State
(a) which element belongs to the 2nd period?
(b) which element belongs to the 2nd group?
(c) which element belongs to the 'zero' group?

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Answer 1

(I) no

(ii) no

12

left to right

atomic size decrease

metallic character decrease

ionization energy increses

13

a no one

b 282

c 288