Find the correct sequence of filling of electrons for an atom having principal quantum number (n) equal to 6.

1. $\mathrm{ns}$ $\stackrel{}{\to }$ $\left(\mathrm{n}-1\right)$ $\mathrm{d}$ $\stackrel{}{\to }$ $\left(\mathrm{n}-2\right)$ $\mathrm{f}$ $\stackrel{}{\to }$ $\mathrm{np}$

2. $\mathrm{ns}$ $-$ $\left(\mathrm{n}-2\right)$ $\mathrm{f}$ $\stackrel{}{\to }$ $\mathrm{np}$ $\stackrel{}{\to }$ $\left(\mathrm{n}-1\right)$ $\mathrm{d}$

3. $\mathrm{ns}$ $-$ $\mathrm{np}$ $\stackrel{}{\to }$ $\left(\mathrm{n}-1\right)\mathrm{d}$ $\stackrel{}{\to }$ $\left(\mathrm{n}-2\right)$ $\mathrm{f}$

4. $\mathrm{ns}$ $\stackrel{}{\to }$ $\left(\mathrm{n}-2\right)$ $\mathrm{f}$ $\stackrel{}{\to }$ $\left(\mathrm{n}-1\right)$ $\mathrm{d}$ $\stackrel{}{\to }$ $\mathrm{np}$

The rule used to determine the maximum number of electrons in a subshell of an atom is:

Which of the following sets of quantum numbers is incorrect?
1. n= 4, l= 0, m= 0, s= -1/2
2. n= 5, l= 3, m= 0, s= +1/2
3. n= 3, l= 2, m= -3, s= -1/2
4. n= 3, l= 2, m= 2, s= -1/2

The orbital diagram in which both Pauli's exclusion principle and Hund's rule are violated is: 
 

1.
2.
3.
4.

Which of the following represents the correct order of the total number of nodes in atomic orbitals?

1.  4f > 6s > 5d

2.  6s > 5d > 4f

3.  4f > 5d > 6s

4.  5d > 4f > 6s

Which of the following statements correctly describes the number of nodes in an atomic orbital?

1.  Number of angular nodes = n - l - 1

2.  Number of radial nodes = l

3.  Total number of nodes = n -1

4.  All of the above

Orbitals having two spherical nodes are: 

The development of the wave mechanical model of the atom is based on which of the following concepts?

1.  De-Broglie concept of the dual nature of the electron.

2.  Heisenberg uncertainty principle.

3.  Schrodinger's principle

4.  All of the above

Which of the following statements about the properties of X-rays is incorrect?

1.  X-rays can ionize gases.

2.  X-rays produce fluorescence in zinc sulphide (ZnS).

3.  X-rays are deflected by electric and magnetic fields.

4.  X-rays have shorter wavelengths than ultraviolet rays.

For any H-like system, the ratio of velocities of I, II & III orbit i.e., ${\mathrm{V}}_1<mspace\; width="1em"></mspace>:<mspace\; width="1em"></mspace>{\mathrm{V}}_2<mspace\; width="1em"></mspace>:<mspace\; width="1em"></mspace>{\mathrm{V}}_3$ will be:

1.  1 : 2 : 3

2.  1 : 1/2 : 1/3

3.  3 : 2 : 1

4.  1 : 1 : 1