The total energy of 1 mol of photons in J/mol having \(\lambda = 600 \ nm \) is:

Given: \(h = 6.62 \times 10^{-34} \mathrm{~J} \ \mathrm{sec}, \mathrm{c}=3 \times 10^{8} \mathrm{~m \ s}^{-1}\)

1. \(2 \times 10^5 J/mol\)
2. \(6.64 \times 10^8 J/mol\)
3. \(1.24 \times 10^4 J/mol\)
4. \(1.24 \times 10^8 J/mol\)
Subtopic:  Electromagnetic Radiation |
 69%
Level 2: 60%+
JEE
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The figure that is not a direct manifestation of the quantum nature of atoms is:

1.
2.
3.
4.
Subtopic:  Electromagnetic Radiation |
Level 3: 35%-60%
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The energy of radiation given by \(E=\frac{hc}{\lambda_{\text{absorb}}}. \)
If \(E=+96\text{ kJ}mol^{-1}\), then the value of \(\lambda_{\text{absorb}} \) (in \(A^\circ\)) is:

1. 12471 \(A^\circ\)
2. 124.71 \(A^\circ\)
3. 1247.1 \(A^\circ\)
4. 1.2471 \(A^\circ\)
Subtopic:  Electromagnetic Radiation |
Level 4: Below 35%
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Find out wavelength of a photon having frequency equal to \(900 ~\text {sec}^{-1}\)
1. \(3.33 \times 10^5 \mathrm{~m} \)
2. \(3.33 \times 10^5 \mathrm{~cm} \)
3. \(3.33 \times 10^7 \mathrm{~m} \)
4. \(3.33 \times 10^4 \mathrm{~m}\)
Subtopic:  Electromagnetic Radiation |
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Frequency of following electromagnetic wave is given by ______ x \(10^6 \mathrm{~Hz} .\)
 
1. 25 
2. 67 
3. 98 
4. 23
Subtopic:  Electromagnetic Radiation |
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Wave number of a radiation having 5800Å wavelength is x\(\mathrm{x} \times 10^4 \mathrm{~cm}^{-1} \text {. }\) The value of \(\mathrm{x}\) to nearest integer is :
1. 2 
2. 4 
3. 5 
4. 8
Subtopic:  Electromagnetic Radiation |
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If the energy of radiation having wavelength of 242 nm is \(x\times10^{-19}\text{J},\) then find nearest integer value of x.
Given : Plank's constant = \(6.6\times10^{-19}\) Joule-Second, \(\text{c}=3\times10^{8}\text{ms}^{-1}\)
1. 8 
2. 2 
3. 5 
4. 2
Subtopic:  Electromagnetic Radiation |
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Line corresponding to lyman series are \(L_1,L_2,L_3,L_4.....,\) among these \(L_1\) line corresponds to lowest energy. Similarly lines corresponding to balmer series are \(B_1,B_2,B_3,B_4....,\) among these \(B_1\) line corresponds to lowest energy:
\(\Delta E_L\) = Energy of \(1^{st}\) line of lyman series
\(\Delta E_B\) = Energy of \(1^{st}\) line of balmer series
If \(\Delta E_L=x.\Delta E_B\). Calculate \((x\times 10^{-1})\):

1. 54
2. 27
3. 40
4. 18
Subtopic:  Electromagnetic Radiation | Type of Spectra |
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Energy of \(1^{st}\) Balmer line of H-atom is x J. The energy (in J) of second Balmer line of H-atom is :

1. x
2. 2x
3. 1.35x
4. \(\dfrac{\mathrm{x}}{1.35}\)
Subtopic:  Electromagnetic Radiation | Type of Spectra |
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On two metal surfaces, a monochromatic light of 6 eV was incident. They have ratio of their work function and maximum KE as
\(\frac{\phi_1}{\phi_2}=\frac{1}{2}, \frac{\left(\mathrm{KE}_{\max }\right)_1}{\left(\mathrm{KE}_{\max }\right)_2}=\frac{2.62}{1}\)

Then \(\phi_1\) and \(\phi_2\) values are respectively (in eV):
1. 2.292, 4.584
2. 4.584, 2.292
3. 4.584, 9.168
4. 1.146, 2.292
Subtopic:  Photo Electric Effect | Electromagnetic Radiation |
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