BITSAT2014ChemistryClassification of Elements and Periodicity in PropertiesActual
Which one of the following arrangements represents the correct order of electron gain enthalpy (with negative sign) of the given atomic species?
Options
- AS < O < Cl < F
- BCl < F < S < O
- CF < Cl < O < S
- DO < S < F < Cl
Correct answer
D. O < S < F < Cl
Step-by-step solution
The amount of energy released when an electron is added to an isolated gaseous atom to produce a monovalent anion is called electron gain enthalpy. Electron affinity value generally increase on moving from left to right in a period however there are exceptions of this rule in the case of those atoms which have stable configuration. These atoms resist the addition of extra electron, therefore the low value of electron affinity -1.48 O < -2.0 ~S < -3.6 ~F < -3.8 Cl On the other hand Cl , because of its comparatively