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Calculate the energy in calories required to produce, from neutral He atoms, 1 mole of (a) `He^(+)` ions (b ) `'He^(+ +)` ions using Bohr's equations

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To calculate the energy required to produce 1 mole of \( \text{He}^+ \) ions and 1 mole of \( \text{He}^{2+} \) ions from neutral helium atoms using Bohr's equations, we will follow these steps: ### Step 1: Understand the Ionization Process - **Neutral Helium Atom**: The neutral helium atom has an atomic number \( Z = 2 \). - **Ionization**: To form \( \text{He}^+ \), one electron is removed from the neutral helium atom. To form \( \text{He}^{2+} \), two electrons are removed. ### Step 2: Calculate the Ionization Energy for \( \text{He}^+ \) - The formula for the ionization energy (IE) in the nth orbit is given by: \[ \text{IE} = -\frac{13.6 \, \text{eV} \cdot Z^2}{n^2} \] - For \( \text{He}^+ \): - \( Z = 2 \) - \( n = 1 \) Substituting these values: \[ \text{IE}_{\text{He}^+} = -\frac{13.6 \cdot 2^2}{1^2} = -\frac{13.6 \cdot 4}{1} = -54.4 \, \text{eV} \] ### Step 3: Convert Ionization Energy to Calories - To convert electron volts to calories, we use the conversion factor: \[ 1 \, \text{eV} = 1.6 \times 10^{-19} \, \text{J} \] \[ 1 \, \text{cal} = 4.184 \, \text{J} \] Therefore, the conversion from eV to calories is: \[ 1 \, \text{eV} = \frac{1.6 \times 10^{-19}}{4.184} \approx 3.83 \times 10^{-20} \, \text{cal} \] - Now, converting \( -54.4 \, \text{eV} \) to calories: \[ \text{Energy in calories} = -54.4 \times 3.83 \times 10^{-20} \approx -2.08 \times 10^{-19} \, \text{cal} \] ### Step 4: Calculate the Energy for 1 Mole of \( \text{He}^+ \) - Since we need the energy for 1 mole (Avogadro's number \( N_A = 6.022 \times 10^{23} \)): \[ \text{Energy for 1 mole} = -2.08 \times 10^{-19} \times 6.022 \times 10^{23} \approx -125.1 \, \text{cal} \] ### Step 5: Calculate the Ionization Energy for \( \text{He}^{2+} \) - For \( \text{He}^{2+} \): - \( Z = 2 \) - \( n = 1 \) Using the same formula: \[ \text{IE}_{\text{He}^{2+}} = -\frac{13.6 \cdot 2^2}{1^2} = -54.4 \, \text{eV} \] ### Step 6: Convert Ionization Energy for \( \text{He}^{2+} \) to Calories - The energy in calories for \( \text{He}^{2+} \) is the same as for \( \text{He}^+ \) since the calculation is identical: \[ \text{Energy for 1 mole of } \text{He}^{2+} = -125.1 \, \text{cal} \] ### Final Results - Energy required to produce 1 mole of \( \text{He}^+ \): **-125.1 cal** - Energy required to produce 1 mole of \( \text{He}^{2+} \): **-125.1 cal**

To calculate the energy required to produce 1 mole of \( \text{He}^+ \) ions and 1 mole of \( \text{He}^{2+} \) ions from neutral helium atoms using Bohr's equations, we will follow these steps: ### Step 1: Understand the Ionization Process - **Neutral Helium Atom**: The neutral helium atom has an atomic number \( Z = 2 \). - **Ionization**: To form \( \text{He}^+ \), one electron is removed from the neutral helium atom. To form \( \text{He}^{2+} \), two electrons are removed. ### Step 2: Calculate the Ionization Energy for \( \text{He}^+ \) - The formula for the ionization energy (IE) in the nth orbit is given by: ...
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