a) Air is first passed through concentrated sodium hydroxide to remove carbon (IV) oxide. It is then cooled to -25oC to remove water. through repeated compression and expansion, air is cooled to liquid at -200oC.
b) (i) Sulphuric (IV) acid
ii) $H_2SO_{4(aq)} + SO_{3(g)} \rightarrow H_2S_2O_{7(l)}$
johnmulu answered the question on April 20, 2017 at 09:25
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