jjmiyhnujy

2 năm trước

Xác định CTPT củaA chứa 85.81%C ; 14,29%C biết 1 lít khí A ở đttc nặng 1,25g?

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nguyentransondhy

2 năm trước

Đáp án:

C2H4

Giải thích các bước giải:

Ta có: nA=1/22,4 mol

-> MA=mA/nA=1,25/(1/22,4)=28

A chứa 85,71% C và 14,29% H -> A có dạng CxHy

-> 12x+y=28

->%C=12x/28=85,71% -> x=2 -> y=4 -> C2H4

Văn Giang

2 năm trước

Đáp án: Bn tham khảo nha.

nA=5\112mol =>MA=28 g\mol

Gọi Ct của A là CxHy ta có

12x\%C=y\%H=MA\100

<=> 12x\85,81=28\100 =>x=2

<=> y\14,29=28\100 => y=4

Vậy A là C2H4

Giải thích các bước giải:

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Xác định CTPT củaA chứa 85.81%C ; 14,29%C biết 1 lít khí A ở đttc nặng 1,25g?

2 câu trả lời

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Choose the best answer.I think that ______ cauliflower is not enough for 3 people. Let’s buy one more.

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