trả lời:
C4H10
giải thích:
Đặt CTPT X là CnH2n+2
2,9n/(14n+2) = 4,48/22,4 ⇒ n = 4
⇒ CTPT: C4H10
Vì X là Ankan nên ta có CTPT là: $C_{n}$ $H_{2n+2}$
Ta có:
2,9n/(14n+2)=4,48/22,4=0,2
==> n=4
Vậy CTPT của X là: C4H10.
Nếu đươc làm cử tri em sẽ chọn những ngừời như thế nào vào làm đại biểu quốc hội hoặc hội đồng nhân dân các cấp
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