In what respect will two dry samples of nitrogen gas differ from each other if sample 1 is prepared by completely removing CO₂ and O₂ from air, and sample 2 is prepared by passing purified nitrogen(i)oxide over heated copper? sample 1 is

• A.purer than sample 2
• B.slightly denser than sample 2
• C.in all respects the same as sample 2
• D.colourless but sample 2 has a light brown colour
• E.slightly less reactive than sample 2