If electron has spin quantum number +1/2 and magnetic quantum number -1, it cannot be present in
Options
(a) d-orbital (b) f-orbital (c) p-orbital (d) s-orbital
Correct Answer:
s-orbital
Explanation:
No explanation available. […]
If r is the radius of the first orbit, the radius of nth-orbit of H-atom is given by
Options
(a) rn² (b) rn (c) r/n (d) r² n²
Correct Answer:
rn²
Explanation:
Radius […]
In the cyanide ion, the formal negative charge is on
Options
(a) C (b) N (c) Both C and N (d) resonate between C and N
Correct Answer:
resonate between C and N
Which of the following elements will have the lowest first ionisation energy?
Options
(a) Li (b) Mg (c) Ca (d) Rb
Correct Answer:
Rb
Explanation:
Rb belongs to I-A group and has maximum […]
When the first ionisation energies are plotted against atomic number, the peaks are occupied
Options
(a) alkali metals (b) halogens (c) transition metals (d) rare gases
Correct Answer:
rare gases
Explanation:
Rare gases […]
Pauling’s electro negativity values for elements are useful in predicting
Options
(a) Polarity of the molecules (b) Position in the E.M.F. series (c) Coordination numbers (d) Dipole moments
Correct Answer:
Polarity of the […]
What is the packet of energy called?
Options
(a) Electron (b) Photon (c) Positron (d) Proton
Correct Answer:
photon
Explanation:
According to Planck’s quantum theory of radiation, radient energy is emitted or absorbed […]
The shape of IF₇ molecule is
Options
(a) octahedral (b) trigonal bipyramidal (c) tetrahedral (d) pentagonal bipyramidal
Correct Answer:
pentagonal bipyramidal
Explanation:
Number of hybrid orbitals, H = 1/2 [V + M + […]
Which of the following species contains three bond pairs and one lone pair around the central atom?
Options
(a) H₂O (b) BF₃ (c) NH₂⁻ (d) PCl₃
Correct Answer:
PCl₃
Explanation:
PCl₃ is central […]
In a given atom no two electrons can have the same values for all the four quantum numbers.This is called
Options
(a) Hund’s Rule (b) Aufbau principle (c) Uncertainty principle (d) Pauli’s Exclusion […]
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