The ionization enthalpy of a hydrogen atom is 1.312 × 106Jmol−1. The energy required to excite the electron in the atom from n = 1 to n = 2 is
8.51 × 105 Jmol−1
6.56 × 105 Jmol−1
7.56 × 105 Jmol−1
7.56 × 105 Jmol−1
Which of the following sets of quantum numbers represents the highest energy of an atom?
n = 3, l = 1, m = 1, s = +½
n = 3, l = 2, m = 1, s = +½
n = 4, l = 0, m = 0, s = +½
n = 4, l = 0, m = 0, s = +½
According to Bohr’s theory, the angular momentum of an electron in 5th orbit is
25h/ π
1.0h/π
10/π
10/π
Uncertainty in the position of an electron (mass = 9.1 × 10–31 kg) moving with a velocity 300 ms–1, accurate upto 0.001%, will be
19.2 × 10–2 m
5.76 × 10–2 m
1.92 × 10–2 m
1.92 × 10–2 m
The “spin-only” magnetic moment [in units of Bohr magneton,(µB )] of Ni2+ in aqueous solution would be (Atomic number of Ni = 28)
2.84
4.90
1
1
Which of the following sets of quantum numbers is correct for an electron in 4f orbital?
n = 4, I =3, m = +4, s = + 1/ 2
n = 3, I = 2, m = -2, S = + 1/2
n =4, I = 3, m = +1, s = + 1/ 2
n =4, I = 3, m = +1, s = + 1/ 2
Consider the ground state of Cr atom (Z = 24). The number of electrons with the azimuthal quantum numbers I =1 and 2 are respectively
12 and 4
16 and 5
16 and 4
16 and 4
D.
16 and 4
The wavelength of the radiation emitted, when in hydrogen atom electron falls from infinity to stationary state 1, would be (Rydberg constant = 1.097×107 m-1)
91 nm
9.1×10-8 nm
406 nm
406 nm
If the given four electronic configurations,
(i) n = 4, l = 1
(ii) n = 4, l = 0
(iii) n = 3, l = 2
(iv) n = 3, l = 1
are arranged in order of increasing energy, then the order will be
(iv) < (ii) < (iii) < (i)
(ii) < (iv) < (i) < (iii)
(i) < (iii) < (ii) < (iv)
(iii) < (i) < (iv) < (ii)
Which of the following sets of quantum numbers represents the 19th electron of Cr(Z = 24)?
(4, 1, -1, +)
(4, 0, 0, +)
(3, 2, 0, -)
(3, 2, -2, +)