The magnetic quantum number for the last electron in sodium atom is equal to
2
3
0
1
The velocity of an electron in the third orbit of hydrogen atom is
7.27 × 107 cms-1
7.27 × 10-7 cms-1
3.64 × 107cms-1
None of these
The number of electrons in K19 which have n = 3 and l = 1 is
6
8
The fundamental particle which is responsible for keeping the nucleons together is
Electron
Proton
Positron
Meson
The observation that the ground state of nitrogen atom has 3 unpaired electrons in its electronic configuration is associated with
Heisenberg's uncertainty principle
Pauli's exclusion principle
Aufbau principle
Hund's rule of maximum multiplicity
Which orbit of He+ ion has h/π as its angular momentum of the electron ?
First
Second
Third
Fourth
When alpha particles are passed through a thin metal foil, most of them go straight through the foil because
Alpha particles are positively charged
Alpha particles are much heavier than electron.
Most part of the atom is empty.
Alpha particles move with high velocity
The energy of an electron in the 3rd Bohr orbit of hydrogen atom is -E. Then the energy of the electron in the first orbit will be
4 E
-E/6
-E/2
-9 E
Which orbital have zero electron density in xy plane ?
pz
dz2
dxy
dx2 - y2
The wave number of the first line of Balmer series of hydrogen is 15200cm-1. The wave number of the first line of He+ is
30400cm-1
60800cm-1
76000cm-1
45600cm-1
