Which of the following statements do not form a part of Bohr's model of hydrogen atom ?
Energy of the electrons in the orbits are quantized
The electron in the orbit nearest the nucleus has the lowest energy
Electrons revolve in different orbits around the nucleus
The position and velocity of electrons in the orbit cannot be determined simultaneously
If uncertainty in position and momentum are equal, then uncertainty in velocity is
The number of spherical nodes in 3p orbital is/are
one
three
two
None of these
The position of both, an electron and a helium atom is known within 1.0 mm. Further the momentum of the electron is known within 5.0×10-26 kg ms-1 .The minimum uncertainty in the measurement of the momentum of the helium atom is
50 kg ms-1
80 kg ms-1
80×10-26 kg ms-1
5.0×10-26 kg ms-1
The radius of hydrogen atom in the ground state is 0.53 Å. The radius of Li2+ ion (atomic number = 3) in a similar state is
0.17 Å
0.53 Å
0.265 Å
1.06 Å
10 g of hydrogen and 64 g of oxygen were filled in a steel vessel and exploded. Amount of water produced in this reaction will be
2 moles
3 moles
4 moles
1 mole
The frequency of radiation emitted when the electron falls from n = 4 to n = 1 in a hydrogen atom will be (Given ionisation energy of H = 2.18×10-18 J atom-1 and h = 6.625×10-34 Js)
1.54×1015 s-1
1.03×1015 s-1
3.08×1015 s-1
2.00×1015 s-1
Which of the following is not permissible arrangement of electrons in an atom ?
n = 4, l = 0, m = 0, s = -1/2
n = 5, l = 3, m = 0, s = + 1/2
n = 3, l = 2, m = -3, s = -1/2
n = 3, l = 2, m = -2, s = -1/2
Maximum number of electrons in a sub shell of an atom in determined by the following
4l + 2
2l + 1
4l -2
2n2
Which of the following is never true for cathode rays ?
They possess kinetic energy
They are electromagnetic waves
They produce heat
They produce mechanical pressure
