giúp mik với ạ
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Những câu hỏi liên quan
NH
1
MN
6 tháng 5 2021
CT : CnH2n+1OH
nCO2 = 13.2/44 = 0.3 (mol)
nH2O = 7.2/18 = 0.4 (mol)
CnH2n+1OH + 3n/2O2 -to-> nCO2 + (n+1)H2O
...........................................n............n+1
...........................................0.3...........0.4
=> 0.4n = 0.3(n+1)
=> n = 3
CTPT : C3H7OH
CTCT :
CH3 - CH2 - CH2 - OH : propan - 1 - ol
CH3 - CH(CH3)-OH : propan - 2 - ol
BT
Bùi Thế Nghị
Giáo viên
5 tháng 5 2021
a) Gọi số mol của phenol và rượu etylic lần lượt là x và y mol
C6H5OH + Na → C6H5ONa + 1/2H2
x -> x/2
C2H5OH + Na → C2H5ONa + 1/2H2
y -> y/2
nH2 = 2,24 : 22,4 = 0,1 mol
Ta có hệ pt \(\left\{{}\begin{matrix}94x+46y=14\\x+y=0,2\end{matrix}\right.\) => x = 0,1 và y = 0,1
=> %mC6H5OH = \(\dfrac{0,1.94}{14}\).100% = 67,14%
<=> %mC2H5OH = 100 - 67,14 = 32,86%
b)Khi X tác dụng với dung dịch brom thì chỉ có phenol phản ứng
C6H5OH + 3Br2 → C6H2OH(Br)3 ↓ + 3HBr
=> mC6H2OH(Br)3 = 0,1.331 = 33,1 gam
c)
mC6H5OH = 0,1.94 = 9,4 gam.
mC2H5OH = 0,1.46 = 4,6 gam.
MH
Giúp mik với, mik đang cần gấp ạ!!!
1
4 tháng 12 2021
a: Xét ΔABC có
M là trung điểm của bC
I là trung điểm của AC
Do đó: MI là đường trung bình của ΔABC
Suy ra: MI=AB/2=3(cm)
HH
0
UT
giúp mik với ạ mik cần gấp chiều thi huhu
0
28. Traffic law must be obeyed by people.
29. Why should homeless people be given more help by the government?
30. No river in the world is longer than the Nile.
31. I went to see a boy whose bike was stolen outside my shop.
32. If my mother has a passport, she can go abroad.
33. If you don't mind me asking, why not purchase the house?
34. If the house is cheap, he can buy it.
35. Mr Nam said he had gone abroad for a holiday the year before.
36. He said he had finished his project the day before.
37. Tea can't be made with water by people
38. Messi is the most skillful in the club.
39.The boy whose his parents are my father's friend is naughty.
40. I like the students whose behaviour is good.
41. The building which is the tallest in the city near my house.
42. Mr Nam said he had done his homework the night before .
28 Traffic law must be obeyed
29 Why should more help be given to the homeless by government?
30 No river in the world is as long as the Nile
31 I went to see the boy whose bike was stolen outside my shop
32 If my mother had a passport, she could go abroad
33 If I were you, I would buy the house
34 If the house weren't expensive, he could buy it
35 Mr Nam said that he had gone abroad for a holiday the year before