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The ionization enthalpy of hydrogen atom is 1.312 × 10⁶ J mol^−1. The energy required to excite the electron in the atom from n = 1 to n = 2 is
- 8.51 × 10⁵ J mol^−1
- 6.56 × 10⁵ J mol^−1
- 7.56 × 10⁵ J mol^−1
- 9.84 × 10⁵ J mol^−1
Correct answer: 9.84 × 10⁵ J mol^−1
Solution
Ionization energy corresponds to n=1 to infinity. E(1->2) = IE*(1 - 1/2^2) = 1.312e6*0.75 = 9.84e5 J/mol.
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