Paragraph for Question Nos. 41 to 43 In a mixture of H - He + gas (He + is singly ionized He atom), H atoms and He + ions are excited to their respective first excited states. Subsequently, H atoms transfer their total excitation energy to He + ions (by collisions). Assume that the Bohr model of atom is exactly valid. Ques. The quantum number n of the state finally populated in He + ions is 1. 2 2. 3 3. 4 4. 5 4 marks Q. 42 The wavelength of light emitted in the visible region by He + ions after collisions with H atoms is 1. 6.5 × 10 -7 m 2. 5.6 × 10 -7 m 3. 4.8 × 10 -7 m 4. 4.0 × 10 -7 m 4 marks Q. 43 The ratio of the kinetic energy of the n = 2 electron for the H atom to that of He + ion is 1. 2. 3. 1 4. 2

	Paragraph for Question Nos. 41 to 43 In a mixture of H - He+ gas (He+ is singly ionized He atom), H atoms and He+ ions are excited to their respective first excited states. Subsequently, H atoms transfer their total excitation energy to He+ ions (by collisions). Assume that the Bohr model of atom is exactly valid. Ques. The quantum number n of the state finally populated in He+ ions is
	1.	2
	2.	3
	3.	4
	4.	5
4 marks

Q. 42	The wavelength of light emitted in the visible region by He+ ions after collisions with H atoms is
	1.	6.5 × 10-7 m
	2.	5.6 × 10-7 m
	3.	4.8 × 10-7 m
	4.	4.0 × 10-7 m
4 marks

Q. 43	The ratio of the kinetic energy of the n = 2 electron for the H atom to that of He+ ion is
	1.
	2.
	3.	1
	4.	2