Question
Chemistry Question on Classification
The first ionisation potential of Na is 5.1eV. The value of electron gain enthalpy of Na+ will be
A
−2.55eV
B
−5.1eV
C
−10.2eV
D
+2.55eV
Answer
−5.1eV
Explanation
Solution
Na⟶Na++e−FirstIE
Na++e−⟶Na
Electron gain enthalpy of Na+ is reverse of (IE) Because reaction is reverse so
?H(eq)=−5.1eV