2008
Q51
NEET
MCQ
10 Mar 2026
The measurement of the electron position is associated with an uncertainty in momentum, which is equal to 1 $ \times $ 10$-$18 g cm s$-$1. The uncertainty in electron velocity is (mass of an electron is 9 $ \times $ 10$-$28 g)
A.
1 $ \times $ 105 cm s$-$1
B.
1 $ \times $ 1011 cm s$-$1
C.
1 $ \times $ 109 cm s$-$1
D.
1 $ \times $ 106 cm s$-$1
2008
Q52
NEET
MCQ
10 Mar 2026
If uncertainty in position and momentum are equal, then uncertainty in velocity is
A.
${1 \over m}\sqrt {{h \over \pi }} $
B.
$\sqrt {{h \over \pi }} $
C.
${1 \over {2m}}\sqrt {{h \over \pi }} $
D.
$\sqrt {{h \over {2\pi }}} $
2007
Q53
NEET
MCQ
10 Mar 2026
Consider the following sets of quantum numbers :
Which of the following sets of quantum number is not possible ?
| n | l | m | s | ||||
|---|---|---|---|---|---|---|---|
| (i) | 3 | 0 | 0 | +1/2 | |||
| (ii) | 2 | 2 | 1 | +1/2 | |||
| (iii) | 4 | 3 | -2 | -1/2 | |||
| (iv) | 1 | 0 | -1 | -1/2 | |||
| (v) | 3 | 2 | 3 | +1/2 |
Which of the following sets of quantum number is not possible ?
A.
(i), (ii), (iii) and (iv)
B.
(ii), (iv) and (v)
C.
(i) and (iii)
D.
(ii), (iii) and (iv)
2006
Q54
NEET
MCQ
10 Mar 2026
The orientation of an atomic orbital is governed by
A.
principal quantum number
B.
azimuthal quantum number
C.
spin quantum number
D.
magnetic quantum number.
2006
Q55
NEET
MCQ
10 Mar 2026
Given : The mass of electron is 9.11 $ \times $ 10$-$31 kg, Planck constant is 6.626 $ \times $ 10$-$34 J s, the uncertainty involved in the measurement of velocity within a distance of 0.1 $\mathop A\limits^ \circ $ is
A.
5.79 $ \times $ 105 m s$-$1
B.
5.79 $ \times $ 106 m s$-$1
C.
5.79 $ \times $ 107 m s$-$1
D.
5.79 $ \times $ 108 m s$-$1
2005
Q56
NEET
MCQ
10 Mar 2026
The energy of second Bohr orbit of the hydrogen atom is $-$328 kJ mol$-$1; hence the energy of fourth Bohr orbit would be
A.
$-$ 41 kJ mol$-$1
B.
$-$82 kJ mol$-$1
C.
$-$164 kJ mol$-$1
D.
$-$1312 kJ mol$-$1
2004
Q57
NEET
MCQ
10 Mar 2026
The frequency of radiation emitted when the electron falls from n = 4 to n = 1 in hydrogen atom will be (Given ionization energy of H = 2.18 $ \times $ 10$-$18 J atom$-$1 and h = 6.625 $ \times $ 10$-$34 J s)
A.
1.54 $ \times $ 1015 s$-$1
B.
1.03 $ \times $ 1015 s$-$1
C.
3.08 $ \times $ 1015 s$-$1
D.
2.00 $ \times $ 1015 s$-$1
2003
Q58
NEET
MCQ
10 Mar 2026
The velocity of Planck's constant is 6.63 $ \times $ 10$-$34 J s.
The velocity of light is 3.0 $ \times $ 108 m s$-$1. Which value is closest to the wavelength in nanometers of a quantum of light with frequency of 8 $ \times $ 1015 s$-$1 ?
The velocity of light is 3.0 $ \times $ 108 m s$-$1. Which value is closest to the wavelength in nanometers of a quantum of light with frequency of 8 $ \times $ 1015 s$-$1 ?
A.
2 $ \times $ 10$-$25
B.
5 $ \times $ 10$-$18
C.
$4 \times {10^1}$
D.
3 $ \times $ 107
2002
Q59
NEET
MCQ
10 Mar 2026
In hydrogen atom, energy of first excited state is $-$ 3.4 eV. Then find out K.E. of same orbit of hydrogen atom
A.
+3.4 eV
B.
+6.8 eV
C.
$-$ 13.6 eV
D.
+13.6 eV
2001
Q60
NEET
MCQ
10 Mar 2026
The following quantum numbers are possible for how many orbitals :
n = 3, $l$ = 2, m = +2 ?
n = 3, $l$ = 2, m = +2 ?
A.
1
B.
2
C.
3
D.
4
2001
Q61
NEET
MCQ
10 Mar 2026
Main axis of a diatomic molecule is z, molecular orbital px and py overlap to from which of the following orbitals.
A.
$\pi $ molecular orbital
B.
$\sigma $ molecular orbital
C.
$\delta $ molecular orbital
D.
No bond will form
2000
Q62
NEET
MCQ
10 Mar 2026
Isoelectronic species are
A.
CO, CN$-$, NO+, C${_2^{2 - }}$
B.
CO$-$, CN, NO,
C.
$C_2^ - $
D.
CO, CN, NO, C2
2000
Q63
NEET
MCQ
10 Mar 2026
For given energy, E = 3.03 $ \times $ 10$-$19 Joules corresponding wavelength is (h = 6.626 $ \times $ 10$-$34 J sec, c = 3 $ \times $ 108 m/sec)
A.
65.6 nm
B.
6.56 nm
C.
3.4 nm
D.
656 nm