The set of quantom number for 19th electrons of chromium(Z=24) is
Options
(a) 4,0,0,+½ (b) 4,1,-1,+½ (c) 3,2,2,+½ (d) 3,2,-2,+½
Correct Answer:
4,0,0,+½
Explanation:
(Z= 24) ≡ 1s²,2s²,2p⁶,3s²,3p⁶,4s¹,3d⁵ For 19th electron (i.e.,4s¹) n=4,n […]
The ratio of the difference in energy between first and second Bohr orbit to that between the second and the third Bohr orbit is
Options
(a) 1/2 (b) 1/3 (c) 4/9 (d) 27/5
The wavelength correspending to maximum enregy for hydrogen is 91.2 nm. The corresponding wavelength for He⁺ ion is
Options
(a) 2.28 nm (b) 22.8 nm (c) 182.4 nm (d) 364.8 nm
Correct Answer: […]
According to Bohr’s theory, the angular momentum of electron in 5th orbit is
Options
(a) 25 h/π (b) 1.0 h/π (c) 10 h/π (d) 2.5 h/π
Correct Answer:
2.5 h/π
Explanation:
Angular momentum […]
The ratio of area covered by second orbital to the first orbital is
Options
(a) 1 : 2 (b) 1 : 16 (c) 8 : 1 (d) 16 : 1
Correct Answer:
16 […]
If uncertainty in position and momentum are equal, then uncertainty in velocity is :
Options
(a) 1/2m x √(h/π) (b) √(h/2π) (c) 1/m x √(h/π) (d) √(h/π)
Correct Answer:
1/2m x √(h/π)
Explanation: […]
A 0.66 kg ball is moving with a speed of 100 m/s. The associated wavelength will be(h=6.6 x 10⁻³⁴ Js)
Options
(a) 1.0 x 10⁻³² m (b) 6.6 x 10⁻³² m (c) 6.6 […]
What is the ratio of mass of an electron to the mass of a proton?
Options
(a) 1 : 1 (b) 1 : 2 (c) 1 : 3 (d) 1 : 1837
Correct […]
The radius of hydrogen atom in the ground state is 0.53 Å. The radius of Li2+ ion (atomic number = 3) in a similar state is
Options
(a) 0.17 Å (b) 0.265 Å […]
In hydrogen atom, energy of first excited state is –3.4 eV. Find out KE of the same orbit of Hydrogen atom
Options
(a) +3.4 eV (b) +6.8 eV (c) –13.6 eV (d) +13.6 […]
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