chem 急問!! 聽日考na!!

1.
Ethyl ethanaote is a common organic solvent, which can dissolve expanded polystyrene (an organic substance). Therefore, ethyl ethanoate cannot be held by expanded polystyrene cup.

2.
This is because air does not contain hydrogen. The Earth was cooled down from a hot planet. At high temperature, hydrogen and oxygen reacted to form water. Since oxygen was in excess and hydrogen was the limiting reactants, all hydrogen was reacted and some unreacted oxygen was left in the atmosphere. Therefore, air contains oxygen, but not hydrogen.
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D
Fractional distillation of air usually uses air at -200℃.
Boiling point of hydrogen is below it.

http://en.wikipedia.org/wiki/Hydrogen

1) Both are organic compound. They will dissolve together.



2) fractional distillation is applicable in separating 2 or more '''miscible liquid"" with similar boilin g point.