Last seen: Oct 19, 2020
(e) If the Assertion is incorrect but the Reason is correct. Explanation: Isobars have the same atomic mass (sum of protons and neutrons) but diff...
(c) If the Assertion is correct but Reason is incorrect. Explanation: Atom is electrically neutral. Atoms necessarily contain equal number of prot...
(a) 5 → 2 Explanation: The lines falling in the visible region comprise Balmer series. Hence the third line would be n1 = 2, n2 = 5 i.e. 5 → 2
(d) n = 2 to n = 1 Explanation: For He+ ion, 2s.png
(a) M2 = 2M1 Explanation: 2010Ne contains 10 protons and 10 neutrons ∴ M1 = 10mp + 10mn 4020Ca contains 20 protons and 20 neutrons ∴ M2 = 20...
(c) For n = 1, the electron has a more negative energy than it does for n = 6 which mean that the electron is more loosely bound in the smallest allow...
(c) Paschen series Explanation: Series limit is the last line of the series, i.e. n2 = ∞. ∴ The line belongs to Paschen series. 2s.png
(a) (iv) < (ii) < (iii) < (i) Explanation: (n + l) rule the higher the value of (n + l), the higher is the energy. When (n + l) value is ...
(c) CO, NO+, CN-, C2-2 Explanation: The species CO, NO+, CN- and C2-2 contain 14 electrons each.
(b) n= 2, l = 0, m = 0, ms = - 1/2
(b) 2 : 1 Explanation: E = hc/λ ; E1/E2 = λ2/λ1 = 6000/3000 = 2 : 1
(c) 7.5 × 1021 sec-1 Explanation: Using E = hv, we get v = E/h = 5.0 x 10-5 erg/6.63 x 10-34Js = 5.0 x 10-5 erg/6.63 x 10-34 x 107 erg sec [...
(a) 2 Explanation: Using the relation, Δx.Δv = h/4πm [Heisenberg' uncertainty principle] or ΔxA = h/4π x 0.05 x m .....(i) ΔxB = h/4π x 0...
(a) 6.626 x 10-34 m Explanation: λ = h/mv = h/√2mE = 6.6 x 10-34 /√(2 x 1 x 0.5) = 6.626 x 10-34 m
(c) 26.5 Explanation: Bohr's radius (r) = 0.529 x 10-10n2 / Z m = 52.9 n2/Z pm Here n (No of shell) = 1 Z (At. No) = 2 ∴ r = 52.9 x 12/2 ...
(d) ClO-2 and ClF2+ Explanation: No. of electrons in ClO-2 = 17 + 16 + 1 = 34 No. of electrons in ClF2+ =17 + 9 ×2 – 1 = 34
(b) 7 Explanation: For n = 4 and l = 3, the orbital is 4 f. No. of values of m = (2l + 1) = 7.
(c) the spatial orientation of the orbital Explanation: Magnetic quantum no. ‘m’ represents the spatial orientation of the orbital.
(b) angular momentum of electron Explanation: Azimuthal quantum no. 'm' defines angular momentum of electron.
(a) H Explanation: Li2+ will have only one electron in its outermost electron. Its spectrum will be very similar to that of hydrogen.