What is the wavelength associated with a tennis ball of mass 10³ g and travelling at a velocity of 6.626 ms^-1 ?[h = 6.626 x 10^-34 Js^-1].

• 10^-34 m

• 10^-31 m

• 6.626 m

• 6.626 × 10^-31 m

What is the energy required to move the electron from ground state of H atom to the first excited state? Given that the ground state energy of H atom is 13.6 eV and that the energy E_n of an electron in nth orbital of an atom or ion of atomic number Z is given by the equation En= - (13.6Z² /n²).

• 13.6 eV

• 3.4 eV

• 10.2 eV

• -10.2 eV

243.

Which electron orbitals are designated by
(i) n = 2, l = 1, m = 0;
(ii) n = 3, l=2, m = O;
(iii) n=4, l = 2, m=1 and
(iv) n = 5, l=3, m=3 respectively?

• 2p, 3d, 4d and 5f, respectively

• 2p, 3d, 4d and 5d, respectively

• 2p, 3d, 4f and 5f, respectively

• 2p, 3p, 4d and 5f, respectively

Which one of the following represents the correct ratio of the energy of electron in ground state of H atom to that of the electron in the first excited state of Li⁺?

• 4 : 9

• 9 : 4

• 1 : 4

• 4 : 1

Which one of the following complexes is an outer orbital complex?

(Atomic number of Mn = 25; Fe = 26; Co = 27 and Ni = 28)

• [Fe(CN)₆]^4-

• [Mn(CN)₆]^4-

• [Co(NH₃)₆]³⁺

• [Ni(NH₃)₆]²⁺

Which of the following has the largest number of atoms?

• 0.5 gm atom of Cu

• 0.635 gm of Cu

• 0.25 moles of Cu atoms

• 1 gm of Cu

Which of the following will violate Pauli's exclusion principle?

• 

• 

• Both (a) and (b)

• None of the above

The ratio of the difference in energy between the first and second Bohr orbit to that between the second and third Bohr orbit is

• $\frac{1}{2}$

• $\frac{1}{27}$

• $\frac{4}{9}$

• $\frac{27}{5}$

Which pair of elements has same chemical properties?

• 13, 22

• 3, 11

• 4, 24

• 2, 4

The wave number of hydrogen atom in Lyman series is 82200 cm^-1. The electron goes from

• n₃ → n₂

• n₂ → n₁

• n₄ → n₃

• None of these