Which of the following combination is most likely to form covalent bond/s? Explain.
(i) Sodium and hydrogen (ii) Magnesium and oxygen
(iii) Chlorine and oxygen (iv) Calcium and bromine.
The electronic configurations of sodium, hydrogen, magnesium, oxygen, chlorine and bromine are as follows:
|
Element |
Atomic number |
Electronic configuration |
|
Sodium Hydrogen Magnesium Oxygen Chlorine Bromine |
11 1 12 16 17 20 |
2, 8, 1 1 2, 8, 2 2, 8, 6 2, 8, 7 2,8,8,2 |
(i) Sodium can lose one electron and hydrogen can accept one electron and thus
their combination can form electrovalent bond.
(ii) Magnesium can lose 2 electrons and oxygen can accept 2 electrons and thus this combination can form electrovalent bond.
(iii) Both oxygen and chlorine cannot lose 6 and 7 electrons respectively. This combination is likely to share electrons with each other to satisfy their octets and thus are more likely to form covalent bond.
(iv) Calcium can easily transfer two electrons to two atoms of bromine leading to the formation of electrovalent bond.
Thus combination of chlorine and oxygen is most likely to form two covalent bonds.
