Write down electronic configuration of first 20 elements and also mention their valency , block, period and group in the modern periodic table.
Answers
Answer: The element is calcium(Ca)
(a)2,8,8,2 or
(b)It is a metal
(c)
(d)calcium is more reactive than magnesium since it has another shell which means it's easier for calcium to lose electrons, in other words, calcium is more electropositive than magnesium
Answer:
Element Symbol Atomic Number Valency
Hydrogen H 1 1
Helium He 2 0
Lithium Li 3 1
Beryllium Be 4 2
Boron B 5 3
Carbon C 6 4
Nitrogen N 7 3
Oxygen O 8 2
Fluorine F 9 1
Neon Ne 10 0
Sodium Na 11 1
Magnesium Mg 12 2
Aluminum Al 13 3
Silicon Si 14 4
Phosphorus P 15 3
Sulphur S 16 2
Chlorine Cl 17 1
Argon Ar 18 0
Potassium K 19 1
Calcium Ca 20 2