The shortest wavelength in hydrogen spectrum of Lyman series when RH = 109678 cm-1 is
1002.7 Å
1215.67 Å
1127.30 Å
911.7 Å
The electrons, identified by quantum numbers n and l,
(I) n = 3; l = 2; (II) n = 5; l = 0; (III) n = 4; l = 1; (IV) n = 4; l = 2; (V) n = 4; l = 0;
can be placed in order of increasing energy as-
I < V < III < IV < II
I < V < III < II < IV
V < I < III < II < IV
V < I < II < III < IV
The number of photons emitted per second by a 60 W source of monochromatic light of wavelength 663 nm is (h = 6 .63 × 10-34 Js)
4 × 10-20
1.5 × 1020
3 × 10-20
2 × 1020
Energy released, when one atom of uranium undergoes nuclear fission according to the following reaction is (atomic mass of U = 235.060; n = 1.009; Ba= 143.881 and Kr = 89.94 7) about
92U235 + 0n1 → 56Ba144 + 36Kr90 + 2 0n1
235 MeV
208 MeV
931.5 MeV
5.33 x 1023 MeV
Identify the nuclear reaction that differs from the rest.
γ- decay
κ- capture
Positron emission
β-decay
Which diagram best represents the appearance of the line spectrum of atomic hydrogen in the visible region?
C.
Line spectrum of atomic hydrogen in the visible region.
The correct set of quantum numbers (n, l and m respectively) for the unpaired electron of chlorine atom is :
2, 1, 0
2, 1, 1
3, 1, 1
3, 2, 1
The relationship between the energy E1 of the radiation with a wavelength 8000 Å and the energy E2 of the radiation with a wavelength Å 16000 is:
E1 = 6E2
E1 = 2E2
E1 = 4E2
E1 = 4E2
Calculate the mass loss in the following.
[Given the masses : 2H = 2.014;3H = 3.016; He = 4.004; n = 1.008 amu]
0.018 amu
0.18 amu
0.0018 amu
1.8 amu
The observation that the ground state of nitrogen atom has 3 unpaired electrons in its electronic configuration and not otherwise is associated with:
Pauli's exclusion principle
Hund's rule of maximum multiplicity
Heisenberg's uncertainty relation
Ritz combination principle