The Question is from neet-physics nuclei , and it was created by the author NAGA SAI

Question

Work required to pull an electron from helium atom is 40 eV.  Then the work required to pull both the electrons from the helium atom is

NAGA SAI · Accepted Answer

## CORE INFORMATION
✓ **Answer**: D
## CONCEPT FRAMEWORK
	**Primary Concept**: Ionization Energy
	**Related Topics**: Atomic Structure, Electron Configuration, Nuclear Charge, Electron Shielding
	**Prerequisites**: Understanding of atomic structure, ionization energy, and electron interactions.
## SOLUTION PATHWAY
**Given Information**:
	* Work required to remove the first electron from Helium (He) = 40 eV
	* We need to calculate the work required to remove both electrons.
**Method & Steps**:
	1. **First Ionization**: The first ionization energy of Helium is given as 40 eV. This is the energy required to remove one electron from a neutral Helium atom.
		Reasoning: We are given this value directly in the problem statement.
		Formula/Rule:  $He + Energy ightarrow He^+ + e^-$
	2. **Second Ionization**:  After removing one electron, we are left with $He^+$. The second electron is now more tightly bound to the nucleus because there is only one electron to shield the full +2 charge of the nucleus. The effective nuclear charge is higher making it harder to remove the second electron. We will require more energy to remove the second electron than the first.
		Reasoning: The removal of the first electron exposes the second electron to a greater effective nuclear charge.
		Key Point: The second ionization energy is always greater than the first ionization energy.
	3. **Calculating the second ionization energy**: The second ionization energy for helium is approximately 54.4 eV. 
		Working: Experimental data shows that the second ionization energy of helium is around 54.4 eV.
	4. **Total Energy**: The total work required to remove both electrons is the sum of the first and second ionization energies.
		Result: Total Energy = 40 eV + 54.4 eV = 94.4 eV
		Verification: This result matches the correct answer provided.
## OPTION ANALYSIS
[A] :x: 80 eV - Incorrect. This only considers the same energy for both electrons and doesn't account for the increased nuclear charge after removing the first electron.
[B] :x: 84 eV - Incorrect. This is a random value and does not align with the calculated or expected value.
[C] :x: 40 eV - Incorrect. This only includes the energy to remove the first electron, not the second.
[D] ✓: 94.4 eV - Correct. This is the sum of the first (40 eV) and second (54.4 eV) ionization energies for Helium.
## LEARNING AIDS
	**Common Mistakes**:
		1. **Assuming equal ionization energies**: Forgetting that the second ionization energy is always greater than the first, due to the increased effective nuclear charge.
			How to avoid: Always consider the impact of removing an electron on the remaining electrons.
		2. **Using a simple multiple**: Trying to simply double the first ionization energy.
			How to avoid: Recognize that the electronic structure has changed after each electron removal.
	**Quick Tips**:
		1. **Ionization Energy Trend**: Remember that ionization energy increases as you remove more electrons from an atom.
		2. **Effective Nuclear Charge**: The effective nuclear charge experienced by an electron increases as you remove other electrons.

NAGA SAI · Answer

80 eV

NAGA SAI · Answer

84 eV

NAGA SAI · Answer

40 eV

NAGA SAI · Answer

The correct Option is "94.4 eV"

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