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Consider a hydrogen-like atom whose ener...

Consider a hydrogen-like atom whose energy in nth excited state is given by
`E_(n) = - (13.6 Z^(2))/(n^(2))`
When this excited makes a transition from excited state to ground state , most energetic photons have energy
`E_(max) = 52.224 eV`. and least energetic photons have energy
`E_(min) = 1.224 eV`
Find the atomic number of atom and the initial state or excitation.

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To solve the problem, we will follow these steps: ### Step 1: Write down the energy equations The energy of a hydrogen-like atom in the nth excited state is given by: \[ E_n = -\frac{13.6 Z^2}{n^2} \] where \( Z \) is the atomic number and \( n \) is the principal quantum number. ### Step 2: Determine the energy difference for maximum energy transition The maximum energy photon emitted during the transition from the nth excited state to the ground state (n=1) is given as: \[ E_{max} = E_n - E_1 \] Substituting the energy values, we have: \[ E_{max} = \left(-\frac{13.6 Z^2}{n^2}\right) - \left(-\frac{13.6 Z^2}{1^2}\right) = 13.6 Z^2 \left(1 - \frac{1}{n^2}\right) \] Setting this equal to the given maximum energy: \[ 13.6 Z^2 \left(1 - \frac{1}{n^2}\right) = 52.224 \quad \text{(Equation 1)} \] ### Step 3: Determine the energy difference for minimum energy transition The minimum energy photon emitted occurs when the transition is from the nth excited state to the (n-1)th state: \[ E_{min} = E_n - E_{n-1} \] Substituting the energy values, we have: \[ E_{min} = \left(-\frac{13.6 Z^2}{n^2}\right) - \left(-\frac{13.6 Z^2}{(n-1)^2}\right) = 13.6 Z^2 \left(\frac{1}{(n-1)^2} - \frac{1}{n^2}\right) \] Setting this equal to the given minimum energy: \[ 13.6 Z^2 \left(\frac{1}{(n-1)^2} - \frac{1}{n^2}\right) = 1.224 \quad \text{(Equation 2)} \] ### Step 4: Solve the equations From Equation 1: \[ 13.6 Z^2 \left(1 - \frac{1}{n^2}\right) = 52.224 \] Rearranging gives: \[ Z^2 \left(1 - \frac{1}{n^2}\right) = \frac{52.224}{13.6} \] Calculating the right side: \[ Z^2 \left(1 - \frac{1}{n^2}\right) = 3.84 \quad \text{(Equation 3)} \] From Equation 2: \[ 13.6 Z^2 \left(\frac{1}{(n-1)^2} - \frac{1}{n^2}\right) = 1.224 \] Rearranging gives: \[ Z^2 \left(\frac{1}{(n-1)^2} - \frac{1}{n^2}\right) = \frac{1.224}{13.6} \] Calculating the right side: \[ Z^2 \left(\frac{1}{(n-1)^2} - \frac{1}{n^2}\right) = 0.09 \quad \text{(Equation 4)} \] ### Step 5: Divide Equation 3 by Equation 4 Dividing Equation 3 by Equation 4: \[ \frac{Z^2 \left(1 - \frac{1}{n^2}\right)}{Z^2 \left(\frac{1}{(n-1)^2} - \frac{1}{n^2}\right)} = \frac{3.84}{0.09} \] This simplifies to: \[ \frac{1 - \frac{1}{n^2}}{\frac{1}{(n-1)^2} - \frac{1}{n^2}} = 42.67 \] ### Step 6: Solve for \( n \) Using trial and error, we can substitute values for \( n \) to find a suitable integer. Testing \( n = 5 \): \[ \frac{1 - \frac{1}{25}}{\frac{1}{16} - \frac{1}{25}} = \frac{0.96}{0.09} = 42.67 \] Thus, \( n = 5 \). ### Step 7: Find the atomic number \( Z \) Substituting \( n = 5 \) back into Equation 3: \[ Z^2 \left(1 - \frac{1}{25}\right) = 3.84 \] This simplifies to: \[ Z^2 \cdot \frac{24}{25} = 3.84 \] Solving for \( Z^2 \): \[ Z^2 = \frac{3.84 \cdot 25}{24} = 4 \] Thus, \( Z = 2 \). ### Step 8: Conclusion The atomic number of the atom is \( Z = 2 \) and the initial state of excitation is \( n = 5 \). ---
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