I wish to to know the correct usage of "than" in the following sentences

[1]. The melting temperature of solvent A is comparatively lower than those/than that of other binary solvents involving B and C manufactured by the firm.

[2]. Usain Bolt ran his 100 m final race at London 2012 faster than in 100 m race at Rio 2016.

How to modify [2] such that the second "100 m race" does not appear.

Thank you---Suddhasattwa Ghosh, India