Q15(a). B, I and the bond length of H³⁵Cl
¹H³⁵Cl has a rotational constant of 10.26 cm⁻¹. (i) Explain how the rotational constant is determined from the microwave spectrum. (3 marks) (ii) Calculate the moment of inertia of ¹H³⁵Cl. (4 marks) (iii) Calculate the bond length of the HCl molecule using the above data. (3 marks)
Answer in brief
(i) B = half the line spacing; (ii) I = 2.73 × 10⁻⁴⁷ kg m²; (iii) r = 129.5 pm.
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Coversrotational spectroscopymicrowave spectrumrotational constantmoment of inertiabond length of HCl
All parts of Question 15
- 15(a) B, I and the bond length of H³⁵Cl10 marks
- 15(b) Photolysis of HI: steady-state rate law and quantum yield10 marks