The element with the electronic configuration 1s² 2s²2p⁶3s²3p⁶3d¹⁰4s¹ is

• Cu

• Ca

• Cr

• Co

Which of the following electron has minimum energy?

• n = 4; l = 0; m= 0; s = +$\frac{1}{2}$

• n= 4; l= 1; m = ±1; s = +$\frac{1}{2}$

• n = 5; l = 0; m = 0; s = +$\frac{1}{2}$

• n = 3; l = 2; m = -2; s = +$\frac{1}{2}$

How many emission spectral lines are possible when hydrogen atom is excited to nth energy level?

• $\frac{\mathrm{n}(\mathrm{n}+1)}{2}$

• $\frac{(\mathrm{n}+1)}{2}$

• $\frac{(\mathrm{n}-1)\mathrm{n}}{2}$

• $\frac{{\mathrm{n}}^2}{4}$

Which of the following corresponds to the energy of the possible excited state of hydrogen?

• -13.6 eV

• 13.6 eV

• -3.4 eV

• 3.4 eV

The quantum number of four electrons are given below:

I. n = 4	l = 2	ml = -2	ms = -$\frac{1}{2}$
II. n = 3	l = 2	ml = 1	ms = +$\frac{1}{2}$
III. n = 4	l = 1	ml = 0	ms = +$\frac{1}{2}$
IV. n = 3	l = 1	ml = 1	ms = -$\frac{1}{2}$

The correct order of these increasing energies will be:

• IV > III > II > I

• I > II > III > IV

• I > III > II > IV

• IV > II > III > I

The correct order of the spin only magnetic moment of metal ions in the following low spin complexes, [V(CN)₆]^4-, [Fe(CN)₆]^4-, [Ru(NH₃)₆]³⁺ and [Cr(NH₃)₆]²⁺ is

• V²⁺  > Cr²⁺ > Ru³⁺ > Fe²⁺

• V²⁺ > Ru³⁺ > Cr²⁺ > Fe²⁺

• Cr²⁺ > V²⁺ > Ru³⁺ > Fe²⁺

• Cr²⁺ > Ru³⁺ > Fe²⁺ > V²⁺

517.

Which one of the following about an electron occupying the 1s orbital in a hydrogen atom is incorrect? (The Bohr radius is represented by a₀).

• The electron can be found at a distance 2a₀ from the nucleus.

• The probability density of finding the electron is maximum at the nucleus.

• The total energy of the electron is maximum when it is at a distance a₀ from the nucleus.

• The magnitude of the potential energy is double that of its kinetic energy on a an average.

Hinsberg’s reagent is:

• C₆H₅SO₂Cl

• SOCl₂

• (COCl)₂

• C₆H₅COCl

If p is the momentum of the fastest electron ejected from a metal surface after the irradiation of light having wavelength λ, then for 1.5 p momentum of the photoelectron, the wavelength of the light should be: (Assume kinetic energy of ejected photoelectron to be very high in comparison to work function) :

• $\frac{2}{3}\mathrm{\lambda }$

• $\frac{4}{9}\mathrm{\lambda }$

• $\frac{3}{4}\mathrm{\lambda }$

• $\frac{1}{2}\mathrm{\lambda }$

The degenrate orbitals of [Cr(H₂O)₆]³⁺ are

• d_yz and d_z2

• d_x2 and d_xz

• d_xz and d_yz

• ${\mathrm{d}}_{{\mathrm{x}}^2-{\mathrm{y}}^2}$and d_xy