Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
Bài 6:
\(n_{C_2Ag_2}=\dfrac{24}{240}=0,1\left(mol\right)\)
=> nC2H2 = 0,1 (mol)
Khí thoát ra khỏi dd Br2 là C2H6
\(n_{C_2H_6}=\dfrac{2,24}{22,4}=0,1\left(mol\right)\)
=> \(n_{C_2H_4}=\dfrac{6,72}{22,4}-0,1-0,1=0,1\left(mol\right)\)
\(\left\{{}\begin{matrix}m_{C_2H_2}=0,1.26=2,6\left(g\right)\\m_{C_2H_4}=0,1.28=2,8\left(g\right)\\m_{C_2H_6}=0,1.30=3\left(g\right)\end{matrix}\right.\)
Bài 7:
\(n_{C_3H_3Ag}=\dfrac{22,05}{147}=0,15\left(mol\right)\)
=> nC3H4 = 0,15 (mol)
Khí thoát ra khỏi binh đựng Br2 là C2H6
\(n_{C_2H_6}=\dfrac{2,24}{22,4}=0,1\left(mol\right)\)
=> \(n_{C_2H_4}=\dfrac{8,96}{22,4}-0,15-0,1=0,15\left(mol\right)\)
\(\left\{{}\begin{matrix}m_{C_2H_4}=0,15.28=4,2\left(g\right)\\m_{C_2H_6}=0,1.30=3\left(g\right)\\m_{C_3H_4}=0,15.40=6\left(g\right)\end{matrix}\right.\)
$C + O_2 \xrightarrow{t^o} CO_2$
$2C + O_2 \xrightarrow{t^o} 2CO$
Gọi $n_{CO_2} = a(mol) ; n_{CO} =b (mol)$
Ta có: $M_B = \dfrac{44a + 28b}{a + b} = 15.2 = 30(1)$
Theo PTHH : $n_{O_2} = a + 0,5b = \dfrac{2,88}{32} = 0,09(2)$
Từ (1)(2) suy ra : a = 0,02 ; b = 0,14
$\%V_{CO_2} = \dfrac{0,02}{0,02 + 0,14}.100\% = 12,5\%$
$\%V_{CO} = 100\% - 12,5\% = 87,5\%$
Câu 9
CTHH: CnH2n+2
\(n_{O_2}=\dfrac{21,84}{22,4}=0,975\left(mol\right)\)
PTHH: CnH2n+2 + \(\dfrac{3n+1}{2}\)O2 --> nCO2 + (n+1)H2O
\(\dfrac{1,95}{3n+1}\)<--0,975
=> \(M_{C_nH_{2n+2}}=14n+2=\dfrac{8,7}{\dfrac{1,95}{3n+1}}=\dfrac{58}{13}\left(3n+1\right)\)
=> n = 4
=> CTPT: C4H10
Câu 12
a) \(n_{H_2O}=\dfrac{16,2}{18}=0,9\left(mol\right)\)
\(n_{CO_2}=\dfrac{30,8}{44}=0,7\left(mol\right)\)
Do nCO2 < nH2O => 2 hidrocacbon là ankan
b)
Gọi công thức chung của 2 ankan là CnH2n+2
\(n_{C_nH_{2n+2}}=0,9-0,7=0,2\left(mol\right)\)
\(\overline{C}=\dfrac{0,7}{0,2}=3,5\)
Mà 2 ankan liên tiếp nhau
=> 2 ankan là C3H8 và C4H10
\(n_{C_4H_{10}}=\dfrac{3,36}{22,4}=0,15\left(mol\right)\)
PT: \(C_4H_{10}+\dfrac{13}{2}O_2\underrightarrow{t^o}4CO_2+5H_2O\)
Theo PT: \(n_{CO_2}=4n_{C_4H_{10}}=0,6\left(mol\right)\Rightarrow V_{CO_2}=0,6.22,4=13,44\left(l\right)\)
\(n_{O_2}=\dfrac{13}{2}n_{C_4H_{10}}=0,975\left(mol\right)\Rightarrow m_{O_2}=0,975.32=31,2\left(g\right)\)
Câu 18:
\(n_{NO}=\dfrac{3,36}{22,4}=0,15\left(mol\right)\\ \text{Đ}\text{ặt}:n_{Al}=a\left(mol\right);n_{Fe}=b\left(mol\right)\left(a,b>0\right)\\ Al+4HNO_3\rightarrow Al\left(NO_3\right)_3+NO+2H_2O\\ Fe+4HNO_3\rightarrow Fe\left(NO_3\right)_3+NO+2H_2O\\ \Rightarrow\left\{{}\begin{matrix}a+b=0,15\\27a+56b=5,5\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}a=0,1\\b=0,05\end{matrix}\right.\\ \Rightarrow\%m_{Al}=\dfrac{0,1.27}{5,5}.100\approx49,091\%;\%m_{Fe}\approx50,909\%\\ b,n_{HNO_3}=4.n_{NO}=0,6\left(mol\right)\\ V_{\text{dd}HNO_3}=\dfrac{0,6}{0,3}=2\left(M\right)\)
c) Dung dịch Y là dung dịch nào?
\(2M+xH2SO4-->M2\left(SO4\right)x+xH2\)
\(n_M=\frac{23,4}{M}\left(mol\right)\)
\(n_{M2\left(SO4\right)x}=\frac{52,2}{2M+96x}\left(mol\right)\)
Theo pthh
\(n_M=2n_{M2\left(SO4\right)x}\)
\(\Rightarrow\frac{23,4}{M}=\frac{104,4}{2M+96x}\Rightarrow104,4M=46,8M+2246,4x\)
\(\Rightarrow57,6M=2246,4x\Rightarrow M=\frac{2246,4x}{57,6}\)
\(x=1\Rightarrow M=39\left(K\right)\)
Vậy M là Kali