Problem 1
Millikan's oil drop method is used to determine: (a) Velocity of electron (b) Mass of electron (c) Charge of electron (d) \(\mathrm{e} / \mathrm{m}\) ratio of electron
Problem 3
To explain the structure of atom the first use of quantum theory was made by: (a) Heisenberg (b) Bohr (c) Planck (d) Einstein
Problem 4
What is the packet of energy called? (a) Proton (b) Photon (c) Positron (d) Electron
Problem 5
Which one of the following forms a colourless solution in aqueous medium? (a) \(\mathrm{Fe}^{+2}\) (b) \(\mathrm{Cr}^{3+}\) (c) \(\mathrm{Mn}^{+2}\) (d) \(\mathrm{Zn}^{2+}\)
Problem 6
The incorrect configuration is: (a) \(\mathrm{K}=[\mathrm{Ar}] 4 \mathrm{~s}^{1}\) (b) \(\mathrm{Cr}=[\mathrm{Ar}] 3 \mathrm{~d}^{5} 4 \mathrm{~s}^{1}\) (c) \(\mathrm{Cr}=[\mathrm{Ar}] 3 \mathrm{~d}^{4} 4 \mathrm{~s}^{2}\) (d) \(\mathrm{Cu}=[\mathrm{Ar}] 3 \mathrm{~d}^{10} 4 \mathrm{~s}^{1}\)
Problem 7
Which of the following elements has least number of electrons in its \(\mathrm{M}\) shell? (a) \(\mathrm{Mn}\) (b) \(\mathrm{Ni}\) (c) \(\mathrm{K}\) (d) \(\mathrm{Sc}\)
Problem 8
In which orbital the angular momentum of an electron is zero? (a) \(2 \mathrm{p}\) (b) \(2 \mathrm{~s}\) (c) \(3 \mathrm{~d}\) (d) \(4 \mathrm{f}\)
Problem 9
Chromiumis representedby the electronic configuration: (a) \([\mathrm{Ne}] 3 \mathrm{~s}^{2} 3 \mathrm{p}^{6} 3 \mathrm{~d}^{1} 4 \mathrm{~s}^{2}\) (b) \([\mathrm{Ne}] 3 \mathrm{~s}^{2} 3 \mathrm{p}^{6} 3 \mathrm{~d}^{2} 4 \mathrm{~s}^{1}\) (c) \([\mathrm{Ne}] 3 \mathrm{~s}^{2} 3 \mathrm{p}^{6} 3 \mathrm{~d}^{5} 4 \mathrm{~s}^{1}\) (d) \([\mathrm{Ne}] 3 \mathrm{~s}^{2} 3 \mathrm{p}^{6} 4 \mathrm{~s}^{2} 3 \mathrm{~d}^{4}\)
Problem 10
The correct set of quantum numbers is: (a) \(\mathrm{n}=2, l=1, \mathrm{~m}=-2, \mathrm{~s}=0\) (b) \(\mathrm{n}=2, l=-2, \mathrm{~m}=1, \mathrm{~s}=+\frac{1}{2}\) (c) \(\mathrm{n}=2, l=2, \mathrm{~m}_{-}=-1, \mathrm{~s}=-\frac{1}{2}\) (d) \(\mathrm{n}=2, l=1, \mathrm{~m}=0, \mathrm{~s}=+\frac{1}{2}\)
Problem 11
The values of four quantum numbers of valence electron of an element are \(\mathrm{n}=4, l=0, \mathrm{~m}=0\) and \(\mathrm{s}=+\frac{1}{2} .\) The element is: (a) \(\mathrm{Ti}\) (b) \(\mathrm{K}\) (c) \(\mathrm{Na}\) (d) \(\mathrm{Sc}\)
