Question

4be 6c 8o 5b 13al which is the most electropositive element among these

Answer 1

On moving across a period, electronegativity increases. So, out of Be, B, C, and O, Be would be the most electropositive element.
Now, we have to choose from among Be and Al. Be is slightly more electropositive than Al, E.N. value of Be being 1.57 and that of Al being 1.61, both measured on the Pauling scale.
So, out of the 5 elements, Be is the most electropositive element.

Answer 2

Electronic configuration of the following elements is:

4Be= 2,2

6C= 2,4

8O= 2,6

5B= 2,3

13Al= 2,8,3

13Al is the most electropositive element among these because 4Be ,6C ,8O ,5B belong to the same period, but 13Al belongs to next period. According to the trend,the electropositive character of an element increase as we move from top to bottom in a group of the periodic table. This happens as the tendency of an atom to lose electrons increases due to a decrease in nuclear charge and increase in the number of shells.|| हर हर महादेव ||♡