Indian Forest Service Chemistry Paper I 2023

Q1.

(a) SECTION-A 1. An oxygen atom has a total of eight electrons.

(b) Write the four quantum numbers (in tabular form) for each of the eight electrons in the ground state. Use the Born-Haber cycle to calculate the enthalpy of formation of LiF. Use the following data in the calculation: \Delta H_sub = 161 \text kJ/mol \Delta H_{\textdis} = 79 kJ/mol \Delta H_{\textion} = 531 \text kJ/mol \Delta H_{\textEA} = -328 \text kJ/mol \Delta H_{\textxtal} = -1239 \text kJ/mol Iron
(II) oxide, FeO, crystal has a cubic structure and each edge of the unit cell c ) is 5.0 Å. Taking density of oxide as 4.0 \textg cm^-3, calculate the number of \textFe²⁺ and \textO^2- ions present in each unit cell. Derive the following thermodynamic relations : (d)
(i) S = -(δ A)/(δ T))_V
(ii) P = -(δ A)/(δ V))_T
(iii) S = -(δ G)/(δ T))
(iv) V = (δ G)/(δ P))_T (e) What is meant by ionic atmosphere? How can we eliminate it?
(i) Differentiate between Faraday current and Diffusion current.
(ii) 4 + 4 = 8 Find the wavelength of light emitted when 5 × 10^-28 g particles in a 3 Å

Q1. (a) SECTION-A 1. An oxygen atom has a total of eight electrons.

(a) SECTION-A 1. An oxygen atom has a total of eight electrons.

(b) Write the four quantum numbers (in tabular form) for each of the eight electrons in the ground state. Use the Born-Haber cycle to calculate the enthalpy of formation of LiF. Use the following data in the calculation: \Delta H_sub = 161 \text kJ/mol \Delta H_{\textdis} = 79 kJ/mol \Delta H_{\textion} = 531 \text kJ/mol \Delta H_{\textEA} = -328 \text kJ/mol \Delta H_{\textxtal} = -1239 \text kJ/mol Iron
(II) oxide, FeO, crystal has a cubic structure and each edge of the unit cell c ) is 5.0 Å. Taking density of oxide as 4.0 \textg cm^-3, calculate the number of \textFe²⁺ and \textO^2- ions present in each unit cell. Derive the following thermodynamic relations : (d)
(i) S = -(δ A)/(δ T))_V
(ii) P = -(δ A)/(δ V))_T
(iii) S = -(δ G)/(δ T))
(iv) V = (δ G)/(δ P))_T (e) What is meant by ionic atmosphere? How can we eliminate it?
(i) Differentiate between Faraday current and Diffusion current.
(ii) 4 + 4 = 8 Find the wavelength of light emitted when 5 × 10^-28 g particles in a 3 Å

• (a) SECTION-A 1. An oxygen atom has a total of eight electrons.
• (b) Write the four quantum numbers (in tabular form) for each of the eight electrons in the ground state. Use the Born-Haber cycle to calculate the enthalpy of formation of LiF. Use the following data in the calculation: \Delta H_sub = 161 \text kJ/mol \Delta H_{\textdis} = 79 kJ/mol \Delta H_{\textion} = 531 \text kJ/mol \Delta H_{\textEA} = -328 \text kJ/mol \Delta H_{\textxtal} = -1239 \text kJ/mol Iron

Q2. 2. (a)
(i) One-dimensional box goes from n = 2 to n = 1 level. Verify Hψ = Eψ for the particle in a one-dimensional box.
(ii) Draw the molecular orbital diagram for NO molecule. Predict the magnetic behaviour and bond order. Comment on the stability of NO+ ion.

• (a) (i) one-dimensional box goes from n = 2 to n = 1 level. Verify H\psi = E\psi for the particle in a one-dimensional box.
• (b) Draw the molecular orbital diagram for NO molecule. Predict the magnetic behaviour and bond order. Comment on the stability of NO + ion. Calculate the bond order of the following molecules : |c| O₂ and CO BJKE-U-CHM/42 \overline{\mathbfc}

Q2. (a) (i) one-dimensional box goes from n = 2 to n = 1 level. Verify H\psi = E\psi for the particle in a one-dimensional box.
(ii) 8 + 7 = 15

(a) (i) one-dimensional box goes from n = 2 to n = 1 level. Verify H\psi = E\psi for the particle in a one-dimensional box.
(ii) 8 + 7 = 15

(b) Draw the molecular orbital diagram for NO molecule. Predict the magnetic behaviour and bond order. Comment on the stability of NO + ion. Calculate the bond order of the following molecules : |c| O₂ and CO BJKE-U-CHM/42 \overline{\mathbfc}

• (a) (i) one-dimensional box goes from n = 2 to n = 1 level. Verify H\psi = E\psi for the particle in a one-dimensional box.
• (b) Draw the molecular orbital diagram for NO molecule. Predict the magnetic behaviour and bond order. Comment on the stability of NO + ion. Calculate the bond order of the following molecules : |c| O₂ and CO BJKE-U-CHM/42 \overline{\mathbfc}

Q3. 3. Calculate the bond order of the following molecules: O2 and CO.

Q4. 4. Derive the following thermodynamic relations:
(i) S = - (δA/δT)_V;
(ii) P = - (δA/δV)_T;
(iii) S = - (δG/δT);
(iv) V = (δG/δP)_T.

Q5. 5. What is meant by ionic atmosphere? How can we eliminate it?
(i) Differentiate between Faraday current and Diffusion current.
(ii) Find the wavelength of light emitted when 5 × 10^-28 g particles in a 3 Å.