| The position of eight elements in the Modern Periodic Table is given below where atomic numbers of elements are given in the parenthesis. | ||
| Period No. | ||
| 2 | Li (3) | Be (4) |
| 3 | Na (11) | Mg (12) |
| 4 | K (19) | Ca (20) |
| 5 | Rb (37) | Sr (38) |
| (i) Write the electronic configuration of Ca. | ||
| (ii) Predict the number of valence electrons in Rb. | ||
| (iii) What is the number of shells in Sr? | ||
| (iv) Predict whether K is a metal or a non-metal. | ||
| (v) Which one of these elements has the largest atom in size? | ||
| (vi) Arrange Be, Ca, Mg and Rb in the increasing order of the size of their respective atoms. | ||
Answer:
(i) Electronic configuration of Ca = 2, 8, 8, 2 (ii) Number of valance electrons in Rb = 1 (iii) Number of shells in Sr = 5 (iv) K is a metal (v) Rb is bigger in size (vi) Be < Mg < Ca < Rb
You need to login to perform this action.
You will be redirected in
3 sec
