What is the correct arrangement of the following electromagnetic spectrum in the increasing order of frequency?

1. Cosmic rays < Amber light < Radiation of FM radio < X-rays < Radiation from microwave ovens
2. Radiation from FM radio  < Radiation from microwave oven < Amber light < X- rays < Cosmic rays
3. Radiation from microwave ovens < Amber light < Radiation of FM radio < X-rays < Cosmic rays
4. Cosmic rays < X-rays < Radiation from microwave ovens < Amber light < Radiation of FM radio

Subtopic:  Electromagnetic Radiation |
 73%
Level 2: 60%+
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The longest wavelength doublet absorption transition is observed at 589 and 589.6 nm. The frequency of second transition and energy difference between two excited states are respectively -

1) ν = 9.5 × 108s-1,  E = 3.282 × 10-10 J

2) ν = 1.0 × 108s-1,  E = 16.282 ×10-22 J

3) ν = 5.088 × 1014s-1,  E = 3.312 ×10-22 J

4) ν = 7.0 × 1014s-1,  E = 13.282 × 10-10 J

Subtopic:  Planck's Theory | Electromagnetic Radiation |
 64%
Level 2: 60%+
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The work function of the Cesium atom is \(1.9~\mathrm{eV}.\) What is the threshold frequency of radiation for this atom?

1. \(4.59 \times10^{14}~s^{-1}\) 2. \(8.59 \times10^{14}~s^{-1}\)
3. \(5.59 \times10^{-14}~s^{-1}\) 4. \(65.9 \times10^{14}~s^{-1}\)
Subtopic:  Photo Electric Effect |
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Level 2: 60%+
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The following results were observed when sodium metal was irradiated with different wavelengths. What would be the threshold wavelength based on these observations?
λ (nm) 500 450 400
v × 10–5 (cm s–1) 2.55 4.35 5.35

1)  λ0 = 740 nm

2)  λ0 = 540 nm

3)  λ0 = 640 nm

4)  λ0 = 840 nm

Subtopic:  Photo Electric Effect |
 67%
Level 2: 60%+
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When a photon with a wavelength of 150 pm strikes an atom, one of its inner bound electrons is ejected at a velocity of 1.5 × 107 m s–1 The energy with which it is bound to the nucleus would be:

1. 32.22 × 10–16 J

2. 12.22 × 10–16 J

3. 22.27 × 10–16 J

4. 31.22 × 10–16 J
 

Subtopic:  Photo Electric Effect |
 73%
Level 2: 60%+
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The wavelength for the emission transition, the series to which this transition belongs and the region of the spectrum if it starts from the orbit having a radius of 1.3225 nm and ends at 211.6 pm would be respectively -

1) The transition is from the 5th orbit to the 2nd orbit. It belongs to the Balmer series. wavenumber for the transition is 800 nm

2) The transition is from the 4th orbit to the 2nd orbit. It belongs to the Balmer series. wavenumber for the transition is 634 nm

3) The transition is from the 5th orbit to the 2nd orbit. It belongs to the Balmer series. wavenumber for the transition is 434 nm

4) The transition is from the 6th orbit to the 2nd orbit. It belongs to the Balmer series. wavenumber for the transition is 534 nm

Subtopic:  Hydrogen Spectra |
 59%
Level 3: 35%-60%
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If the position of the electron were measured with an accuracy of +0.002 nm, the uncertainty in the momentum of the electron would be: 

1. 5.637 × 10–23 kg m s–1

2. 4.637 × 10–23 kg m s–1

3. 2.637 × 10–23 kg m s–1

4. 3.637 × 10–23 kg m s–1

Subtopic:  Heisenberg Uncertainty Principle |
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Level 2: 60%+
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The quantum numbers of six electrons are given below. Arrange them in the increasing order of energies:

i. n = 4, l = 2, \(m_l\) = –2 , \(m_s\) = –1/2

ii. n = 3, l = 2, \(m_l\) = 1 , \(m_s\) = +1/2

iii. n = 4, l = 1, \(m_l\) = 0 , \(m_s\) = +1/2

iv. n = 3, l = 2, \(m_l\) = –2 , \(m_s\) = –1/2

v. n = 3, l = 1, \(m_l\) = –1 , \(m_s\) = +1/2

vi. n = 4, l = 1, \(m_l\) = 0 , \(m_s\) = +1/2
 

1. v(3p) < ii(3d) < vi(4p) < i(4d) = iv(3d) < iii(4p)

2. v(3p) < ii(3d) = iv(3d) < iii(4p) = vi(4p) < i(4d)

3. vi(4p) < i(4d) < v(3p) < ii(3d) < iv(3d) < iii(4p)

4. v(3p) < ii(3d) < iv(3d) < iii(4p) < vi(4p) < i(4d)

Subtopic:  AUFBAU Principle |
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Level 2: 60%+
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Which electron in a bromine (Br) atom experiences the lowest effective nuclear charge?
1. 2p and 3p
2. 4p
3. 2p
4. 3p
Subtopic:  Number of Electron, Proton & Neutron |
 74%
Level 2: 60%+
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For each of the following pairs of atomic orbitals, identify the one that experiences a larger effective nuclear charge (\(Z_{\text{eff}}\)):

(i) 2s and 3s, (ii) 4d and 4f, (iii) 3d and 3p.

1. 2s, 4d, 3p

2. 3s, 4f, 3d

3. 3s, 4f, 3p

4. 2s, 4d, 3d

Subtopic:  Pauli's Exclusion Principle & Hund's Rule |
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Level 2: 60%+
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