In the formation of CaO how many electrons are transferred from Ca atom to O atom? (Atomic numbers of oxygen and calcium are 8 and 20 respectively)
- 0
- 1
- 2
- 3
WBBSE
Class X
Physical Science
Ionic and Covalent Bond
01 Mark
2023
c. 2
Explanation:
- Calcium (Z = 20) has electronic configuration: 2, 8, 8, 2 → it loses 2 electrons to become Ca²⁺.
- Oxygen (Z = 8) has electronic configuration: 2, 6 → it needs 2 electrons to complete its octet and become O²⁻.
Hence, in CaO formation, 2 electrons are transferred from Ca to O.
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