Chemistry Question Bank

Bohr's theory is NOT applicable to:

Which of the following statements does NOT form a part of Bohr's model of hydrogen atom?

For a Bohr atom, angular momentum of the electron is (n = 1, 2, 3 …)

The velocity of an electron in the second shell of hydrogen atom is

The most probable radius (in pm) for finding the electron in He⁺ is

Which of the following electronic transitions in a hydrogen atom will require the largest amount of energy?

If the total energy of an electron in the 1st shell of H atom = 0.0 eV (reference shifted), then its potential energy in the 1st excited state would be

The ionization enthalpy of hydrogen atom is 1.312 × 10⁶ J mol⁻¹. The energy required to excite the electron from n = 1 to n = 2 is

The emission spectra of He⁺ ions show 6 different photons. What will be the minimum wavelength during the transition? (R_H = Rydberg constant)

The frequency of light emitted for the transition n = 4 to n = 2 of He⁺ is equal to the transition in H atom corresponding to which of the following?

[Manipal 2008] The radius of the nucleus of mass number A is given by r = 1.25 × 10⁻¹³ × A^(1/3) cm. The radius of the atom is 1.0 Å. For mass number A = 64, the fraction of atomic volume occupied by the nucleus is

[Manipal 2008] Deflection of a few α-particles back on hitting a thin gold foil shows that

[CBSE AIPMT 2008] If uncertainty in position and momentum are equal, then uncertainty in velocity is

[AMU 2009] Probability of finding an electron at the nodal surface is

[Haryana PMT 2009] The number of radial nodes of 3s and 2p-orbitals are respectively

[Haryana PMT 2009] The number of nodal planes in the pₓ orbital is

[AMU 2009] The radius of the Bohr orbit of the H-atom is r. Then the radius of the first orbit of Li²⁺ will be

[Manipal 2009] For f-orbital, the values of magnetic quantum number m are

[Manipal 2009] The uncertainty in position of an electron (m = 9.1 × 10⁻²⁸ g) moving with velocity 3.0 × 10⁴ cm s⁻¹ accurate to 0.011% will be (h = 6.626 × 10⁻²⁷ erg·s)

[CBSE AIPMT 2009] Which of the following is NOT a permissible arrangement of electrons in an atom?

[Haryana PMT 2010] The electronic configuration 1s², 2s², 2p¹ₓ 2p¹ᵧ 2p¹_z for nitrogen (not 1s², 2s², 2p²ₓ 2p¹ᵧ 2p⁰_z) is determined by

[RPMT 2010] Principal, azimuthal and magnetic quantum numbers are respectively related to

[AMU 2010] When the electron of a hydrogen atom jumps from n = 4 to n = 1 state, the number of spectral lines emitted is

[KCET 2010] The wave number of a spectral line in the emission spectrum of hydrogen will be equal to (8/9)R_H if the electron jumps from

[VMMC 2010] Which of the following pairs is isoelectronic?