Chemistry NCERT Exemplar Solutions Class 11th Chapter Two

This is a Assertion and Reason Type Questions as classified in NCERT Exemplar

Ans: option (i)

 As the chemical properties depend upon the number of electrons present in the atom thus the isotopes resemble the same chemical properties as they have the same number of electrons i.e. atomic number.

This is a Matching Type Questions as classified in NCERT Exemplar

Ans:

(i) Cr                  (d)  [Ar] 3d⁵4s²

(ii) Fe²⁺             (c) [Ar]3d⁶4s⁰

(iii)Ni²⁺               (a) [Ar]3d⁸4s⁰

(iv)Cu  (b) [Ar]3d¹⁰4s¹

This is a Matching Type Questions as classified in NCERT Exemplar

Ans:

(i) Photon  (d) Exhibits both momentum and wavelength

(ii) Electron  (d) Exhibits both momentum and wavelength

(iii) ψ 2 (b) Probability density

                                          (c) Always positive value

(iv)  Principal quantum  (a) Value is 4 for N shell 

        number n  (c) Always positive value

This is a Matching Type Questions as classified in NCERT Exemplar

Ans:

(i) X-rays  (d) ν = 10¹⁸Hz

(ii) UV  (c) ν = 10¹⁶Hz

(iii) Long radio waves (a) ν = 10 -10⁴ Hz

(iv)Microwave  (b) ν = 10¹⁰ Hz

This is a Matching Type Questions as classified in NCERT Exemplar

Ans:

(i) Principal quantum number (b) energy and size of orbital

(ii) Azimuthal quantum number (d) shape of the orbital

(iii) Magnetic quantum number (a) orientation of the orbital

(iv) Spin quantum number (c) spin of electron

This is a Matching Type Questions as classified in NCERT Exemplar

Ans:

(i) Cu              (c) 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s¹

(ii) Cu²⁺            (d) 1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁹

(iii) Zn²⁺           (a)1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰

(iv) Cr³⁺          (e) 1s² 2s² 2p⁶ 3s² 3p⁶ 3d³

This is a Multiple Choice Questions as classified in NCERT Exemplar

Ans:  option (i)& (iv)

1. Principal quantum number (n): It represents the size and energy of orbitals.
2. Azimuthal quantum number (l): It represents the subshell and shape of orbitals.
3. Magnetic quantum number (ml): It represents the orientation of the orbitals.
4. Spin quantum number (ms): It represents the direction of spin of electrons in the orbitals.

This is a Multiple Choice Questions as classified in NCERT Exemplar

Ans:  option (i) & (iii)

Isoelectronic species are those species that possess the same number of electrons. Here both Na⁺, Mg²⁺ possess 10 electrons and both Na⁺, O^2– possess 10 electrons.

This is a Multiple Choice Questions as classified in NCERT Exemplar

Ans: option (ii) & (iii)

For the given value of n (principal quantum number) the value of l (Azimuthal quantum number) varies from 0 to n-1. However for the given value of l the m_l (magnetic quantum number) varies from -1 to +1.