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a) PTHH: \(Zn+2HCl\rightarrow ZnCl_2+H_2\uparrow\)
b) Ta có: \(n_{H_2}=\dfrac{2,24}{22,4}=0,1\left(mol\right)=n_{Zn}\) \(\Rightarrow m_{Zn}=0,1\cdot65=6,5\left(g\right)\)
\(\Rightarrow\%m_{Zn}=\dfrac{6,5}{10}\cdot100\%=65\%\) \(\Rightarrow\%m_{Cu}=35\%\)
c) Theo PTHH: \(n_{HCl}=2n_{Zn}=0,2mol\)
\(\Rightarrow m_{ddHCl}=\dfrac{0,2\cdot36,5}{5\%}=146\left(g\right)\)
Sửa đề cho dễ làm : dd K2CO3 13,8%
PTHH: \(2CH_3COOH+K_2CO_3\rightarrow2CH_3COOK+H_2O+CO_2\uparrow\)
a+b) Ta có: \(n_{CH_3COOH}=\dfrac{150\cdot12\%}{60}=0,3\left(mol\right)\)
\(\Rightarrow n_{K_2CO_3}=n_{CO_2}=0,15\left(mol\right)\) \(\Rightarrow\left\{{}\begin{matrix}m_{ddK_2CO_3}=\dfrac{0,15\cdot138}{13,8\%}=150\left(g\right)\\V_{CO_2}=0,15\cdot22,4=3,36\left(l\right)\end{matrix}\right.\)
c) Theo PTHH:: \(n_{CH_3COOK}=0,3\left(mol\right)\) \(\Rightarrow m_{CH_3COOK}=0,3\cdot98=29,4\left(g\right)\)
Mặt khác: \(m_{CO_2}=0,15\cdot44=6,6\left(g\right)\)
\(\Rightarrow m_{dd}=m_{ddCH_3COOH}+m_{ddK_2CO_3}-m_{CO_2}=293,4\left(g\right)\)
\(\Rightarrow C\%_{CH_3COOK}=\dfrac{29,4}{293,4}\cdot100\%\approx10,02\%\)
\(n_{Fe}=\dfrac{11,2}{56}=0,2\left(mol\right)\)
a) PTHH : \(Fe+H_2SO_4\rightarrow FeSO_4+H_2\)
Theo Pt : \(n_{Fe}=n_{H2SO4}=n_{FeSO4}=n_{H2}=0,2\left(mol\right)\)
b) \(V_{H2\left(dktc\right)}=0,2.22,4=4,48\left(l\right)\)
c) \(C_{MddH2SO4}=\dfrac{0,2}{0,2}=1\left(M\right)\)
d) \(m_{muối}=m_{FeSO4}=0,2.152=30,4\left(g\right)\)
a)
$CH_3COOH + NaHCO_3 \to CH_3COONa + CO_2 + H_2O$
b)
n NaHCO3 = n CH3COOH = 100.12%/60 = 0,2(mol)
m dd NaHCO3 = 0,2.84/8% = 210(gam)
c)
n CO2 = n CH3COOH = 0,2(mol)
=> V CO2 = 0,2.22,4 = 4,48(lít)
d)
m dd = m dd CH3COOH + m dd NaHCO3 - m CO2 = 100 + 210 - 0,2.44 = 301,2(gam)
C% CH3COONa = 0,2.82/301,2 .100% = 5,44%
\(n_{CaCO_3}=\dfrac{10}{100}=0,1\left(mol\right)\\ n_{HCl}=\dfrac{150.14,6\%}{100\%}:36,5=0,6\left(mol\right)\)
\(CaCO_3+2HCl\rightarrow CaCl_2+H_2O+CO_2\)
0,1 -------> 0,2 -------->0,1---------------> 0,1
Xét \(\dfrac{0,1}{1}< \dfrac{0,6}{2}\)=> axit dư.
\(n_{HCl.dư}=0,6-0,2=0,4\left(mol\right)\)
\(m_{dd}=10+150-0,1.44=155,6\left(g\right)\)
\(C\%_{CaCl_2}=\dfrac{0,1.111.100\%}{155,6}=7,13\%\)
\(C\%_{HCl}=\dfrac{0,4.36,5.100\%}{155,6}=9,38\%\)
Câu1: Hòa tan 30gam CaCO3 vào dd CH3COOH dư. Tính thể tích CO2 thoát ra( đktc)
CaCO3+2CH3COOH->(CH3COO)2Ca+CO2+H2O
0,3------------------------------------------------------0,3
n CaCO3=\(\dfrac{30}{100}\)=0,3 mol
=>VCO2=0,3.22,4=6,72l
Câu2: Cho 4,6 gam rượu etylic vào dd axit axetic dư. Tính khối lượng etylaxetat thu được( biết hiệu suất phản ứng 30%)
C2H5OH+CH3COOH->CH3COOC2H5+H2O
0,1-------------------------------------------0,1
n C2H5OH=0,1 mol
=>H=30%
m CH3COOC2H5=0,1.88.30%=2,64g
a) \(n_{Br_2\left(p\text{ư}\right)}=\dfrac{200.8\%}{160}=0,1\left(mol\right);n_{hh}=\dfrac{7,437}{24,79}=0,3\left(mol\right)\)
PTHH: \(C_2H_4+Br_2\rightarrow C_2H_4Br_2\)
0,1<-----0,1
b) \(\left\{{}\begin{matrix}\%V_{C_2H_4}=\dfrac{0,1}{0,3}.100\%=33,33\%\\\%V_{CH_4}=100\%-33,33\%=66,67\%\end{matrix}\right.\)
c) \(n_{CH_4}=0,3-0,1=0,2\left(mol\right)\)
PTHH: \(CH_4+2O_2\xrightarrow[]{t^o}CO_2+2H_2O\)
0,2--->0,4
\(C_2H_4+3O_2\xrightarrow[]{t^o}2CO_2+2H_2O\)
0,1--->0,3
\(\Rightarrow V_{O_2}=\left(0,3+0,4\right).24,79=17,353\left(l\right)\)
\(a,n_{Mg}=\dfrac{4,8}{24}=0,2\left(mol\right)\\ Mg+2HCl\rightarrow MgCl_2+H_2\\ b,n_{MgCl_2}=n_{H_2}=n_{Mg}=0,2\left(mol\right)\\ b,V_{H_2\left(25\text{đ}\text{ộ}C,1bar\right)}=0,2.24,79=4,958\left(l\right)\\ c,n_{HCl}=2.0,2=0,4\left(mol\right)\\ m_{\text{dd}HCl}=\dfrac{0,4.36,5.100}{10}=146\left(g\right)\\ m_{\text{dd}A}=m_{Mg}+m_{\text{dd}HCl}-m_{H_2}=4,8+146-0,2.2=150,4\left(g\right)\\ d,C\%_{\text{dd}MgCl_2}=\dfrac{95.0,2}{150,4}.100\approx12,633\%\)
a. PTPỨ: Fe + H2SO4 ---> FeSO4 + H2
b. Ta có: nFe = \(\dfrac{11,2}{56}=0,2\left(mol\right)\)
Theo PT: \(n_{H_2}=n_{Fe}=0,2\left(mol\right)\)
=> \(V_{H_2}=0,2.22,4=4,48\left(lít\right)\)
a, \(CaCO_3+2CH_3COOH\rightarrow\left(CH_3COO\right)_2Ca+CO_2+H_2O\)
b, \(n_{CaCO_3}=\dfrac{10}{100}=0,1\left(mol\right)\)
Theo PT: \(n_{CO_2}=n_{CaCO_3}=0,1\left(mol\right)\Rightarrow V_{CO_2}=0,1.22,4=2,24\left(l\right)\)
c, \(n_{\left(CH_3COO\right)_2Ca}=n_{CaCO_3}=0,1\left(mol\right)\)
\(n_{CH_3COOH}=2n_{CaCO_3}=0,2\left(mol\right)\Rightarrow m_{CH_3COOH}=0,2.60=12\left(g\right)\)
\(\Rightarrow m_{ddCH_3COOH}=\dfrac{12}{5\%}=240\left(g\right)\)
Ta có: m dd sau pư = 10 + 240 - 0,1.44 = 245,6 (g)
\(\Rightarrow C\%_{\left(CH_3COO\right)_2Ca}=\dfrac{0,1.158}{245,6}.100\%\approx6,43\%\)
a)
$CaCO_3 + 2CH_3COOH \to (CH_3COO)_2Ca + CO_2 + H_2O$
b)
$n_{CaCO_3} = \dfrac{10}{100} = 0,1(mol)$
Theo PTHH :
$n_{CO_2} = n_{CaCO_3} = 0,1(mol)$
$V_{CO_2} = 0,1.22,4 = 2,24(lít)$
c)
$n_{CH_3COOH} = 2n_{CaCO_3} = 0,2(mol)$
$m_{dd\ CH_3COOH} = \dfrac{0,2.60}{5\%} = 240(gam)$
$m_{dd\ sau\ pư} = 10 + 240 - 0,1.44 = 245,6(gam)$
$n_{(CH_3COO)_2Ca} = n_{CaCO_3} = 0,1(mol)$
$C\%_{(CH_3COO)_2Ca} = \dfrac{0,1.158}{245,6}.100\% = 6,4\%$