The most probable radius (in pm) for finding the electron in He+ is
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NEET Practice Questions (MCQs) with Answers & Solutions
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If the speed of electron in Bohr first orbit of hydrogen atom be x, then speed of the electron in 3rd orbit is
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If wavelength of photon is $ 2·2 \times 10 ^{– 11} m , h= 6·6 \times 10^{–34} Js$ , then momentum of photon is
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The wave number of first line of Balmer series of hydrogen is $ 15200 cm^{–1}. The wave number of the first Balmer line of Li^{1+} $ ion is
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Explanation
As we know the energy of constant state for hydrogen species like Li^+2 or He^+ are multiple of integral type of Z^2 times the energy of hydrogen atom in stationary form
Hence the wave number of first line of ion = 3^2 * 15200 / cm
= 9 * 15200 / cm = 136800 / cm
The electrons, identified by quantum number n andl (i) n = 4, l = 1 (ii) n = 4, = 0 (iii) n = 3, = 2 (iv) n = 3, = 1 can be placed in order of increasing energy, from the lowest to highest, as
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The radius of which of the following orbits is same as that of the first Bohr’s orbit of hydrogen atom ?
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Explanation
The radius of the Bohr orbit is given by the formula r = n^2 * a0, where a0 is the Bohr radius (0.529 Ã…). For n = 2, the radius is 4 times the Bohr radius. The nuclear charge of Be^3+ is 4, which is the same as that of hydrogen. Hence, the radius of the n = 2 orbit of Be^3+ is the same as the first Bohr orbit of hydrogen.
Radial nodes present in 3s and 2p -orbitals are respectively
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Explanation
The number of radial nodes in an orbital is given by the principal quantum number (n) minus the azimuthal quantum number (l) minus 1. For 3s orbital, n = 3, l = 0, so radial nodes = 3 - 0 - 1 = 2. For 2p orbital, n = 2, l = 1, so radial nodes = 2 - 1 - 1 = 0.
On which factors interface depends ?
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Which of the following phenomenon in not involved in surface chemistry ?
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How much pascal high vacuum is required to achive completely pure surface of metal?
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