If the position of the electron were measured with an accuracy of +0.002 nm, the uncertainty in the momentum of the electron would be: 

1. 5.637 × 10^–23 kg m s^–1

2. 4.637 × 10^–23 kg m s^–1

3. 2.637 × 10^–23 kg m s^–1

4. 3.637 × 10^–23 kg m s^–1

The quantum numbers of six electrons are given below. Arrange them in order of increasing energies. 

1. n = 4, l = 2, ml = –2 , ms = –1/2

2. n = 3, l = 2, ml = 1 , ms = +1/2

The electron of a Br atom that experiences the lowest effective nuclear charge is:

1. 2p and 3p

2. 4p

3. 2p

4. 3p

Among the following pairs of orbitals the orbital that will experience the larger effective nuclear charge respectively is -

(i) 2s and 3s, (ii) 4d and 4f, (iii) 3d and 3p.

1. 2s, 4d, 3p

2. 3s, 4f, 3d

3. 3s, 4f, 3p

4. 2s, 4d, 3d

The unpaired electrons in Al and Si are present in the 3p orbital. The electrons that will experience a more effective nuclear charge from the nucleus are :

1. Electrons in the 3p orbital of silicon

2. Electrons in the 5d orbital of aluminium

3. Electrons in the 3p orbital of aluminium

4. Electrons in the 5p orbital of silicon

Among the given options, the element having the highest number of unpaired electrons in the ground state is

1. P

2. Fe

3. Kr

4. Cr

The number of electrons that can be present in the subshells having m_s value of \(-\frac{1}{2}\) for n = 4 are:

1. 36

2. 4

3. 16

4. 2

The atomic number of elements whose outermost electronic configuration are represented by 3s¹ and 2p⁵ respectively, is:

The circumference of the Bohr orbit for the H atom is related to the de Broglie wavelength associated with the electron revolving around the orbit by the following relation: 

$1.$ $2\mathrm{\pi r}=\mathrm{n\lambda }$

$2.$ $\mathrm{\pi r}$ $=$ $2\mathrm{n\lambda }$

$3.$ $\mathrm{mvr}$ $=$ $\mathrm{n\lambda }$

$4.$ $\mathrm{vr}$ $=$ $2\mathrm{n\lambda }$

Which among the following are isoelectronic species?

1. ${\mathrm{Na}}^{+}, {\mathrm{K}}^{+}, {\mathrm{Ca}}^{2+}, {\mathrm{Mg}}^{2+}$

2. ${\mathrm{Ca}}^{2+}, {\mathrm{Mg}}^{2+}, {\mathrm{S}}^{2-}, {\mathrm{K}}^{+}$

3. ${\mathrm{Ca}}^{2+}, \mathrm{Ar}, {\mathrm{S}}^{2-}, {\mathrm{K}}^{+}$

4. None of the above