Q2(a)(ii). CO₂ linear, SO₂ bent
Explain the following: Carbon dioxide has a linear structure whereas sulphur dioxide is a bend molecule.
Answer in brief
C uses all four valence electrons in two C=O bonds and has no lone pair: two electron domains, linear, 180°. S has six valence electrons: two S=O bonds plus one lone pair, three domains in a trigonal-planar arrangement, so SO₂ is bent (119.5°).
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All parts of Question 2
- 2(a)(i) Dipole moments of CF₄ and CH₂F₂5 marks
- 2(a)(ii) CO₂ linear, SO₂ bent5 marks
- 2(a)(iii) Bond order of NO and NO⁺; magnetic behaviour10 marks
- 2(b) Partition function as a product of two partition functions10 marks
- 2(c) Adsorption theory of catalysis: steps and example10 marks