JEE Main2004ChemistryThermodynamics (C)Actual
The formation of the oxide ion O ²⁻( g ) requires first an exothermic and then an endothermic step as shown below O ( g )+ e ⁻ O ⁻( g ) H ^ =-142 kJmol ⁻¹ O ⁻( g )+ e ⁻ O ²⁻( g ) H ^ =844 kJmol ⁻¹
Options
- AOxygen is more electronegative
- BO ⁻ ion has comparatively larger size than oxygen atom
- CO ⁻ ion will tend to resist the addition of another electron
- DOxygen has high electron affinity
Correct answer
C. O ⁻ ion will tend to resist the addition of another electron
Step-by-step solution
O ⁻¹( ~g )+ e O ⁻²( ~g ) Due to the electronic repulsion, amount of the energy is needed to add electron