cho 0,8g MgO tác dung 50g đ axit sunfuric chx rõ nồng độ sau phản ứng thu đc dd A a) tính nồng độ phần trăm của đ axit phản ứng
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
a)
$n_{Al} = \dfrac{5,4}{27} = 0,2(mol)$
$2Al + 3H_2SO_4 \to Al_2(SO_4)_3 + 3H_2$
Theo PTHH:
$n_{H_2SO_4} = n_{H_2} = \dfrac{3}{2}n_{Al} = 0,3(mol)$
$V_{dd\ H_2SO_4} = \dfrac{0,3}{2} = 0,15(lít)$
$n_{Al_2(SO_4)_3} = \dfrac{1}{2}n_{Al} = 0,1(mol)$
$C_{M_{Al_2(SO_4)_3}} = \dfrac{0,1}{0,15} = 0,67M$
b)
$V_{H_2} = 0,3.22,4 = 6,72(lít)$
![](https://rs.olm.vn/images/avt/0.png?1311)
\(n_{CuO}=\dfrac{3,2}{80}=0,04\left(mol\right)\)
\(n_{H_2SO_4}=\dfrac{100.20\%}{98}=0,204\left(mol\right)\)
PTHH:
\(CuO+H_2SO_4\rightarrow CuSO_4+H_2O\)
0,04 0,04 0,04
\(\dfrac{0,04}{1}< \dfrac{0,204}{1}\) --> H2SO4 dư
\(C\%_{CuSO_4}=\dfrac{0,04.160}{3,2+100}.100\%=6,2\%\)
\(C\%_{H_2SO_4\left(dư\right)}=\dfrac{0,2.98}{3,2+100}.100\%=19\%\)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(n_{Zn}=\dfrac{6,5}{65}=0,1\left(mol\right)\)
PTHH: \(Zn+2HCl\rightarrow ZnCl_2+H_2\)
0,1 0,4
0,1 0,2
0 0,2 0,1 0,1
\(a,V_{H_2}=0,1.22,4=2,24\left(l\right)\\ b,m_{dd}=6,5+0,4.36,5+50-0,1.2=70,9\left(g\right)\\ C\%_{ZnCl_2}=\dfrac{0,1.136}{70,9}.100\%=19,18\%\)
![](https://rs.olm.vn/images/avt/0.png?1311)
a)
$Fe + H_2SO_4 \to FeSO_4 + H_2$
Theo PTHH :
$n_{Fe} = n_{H_2} = \dfrac{3,36}{22,4} = 0,15(mol)$
$m_{Fe} = 0,15.56 = 8,4(gam)$
b)
$n_{H_2SO_4} = n_{H_2} = 0,15(mol)$
$C_{M_{H_2SO_4}} = \dfrac{0,15}{0,05} = 3M$
c)
$n_{FeSO_4} = n_{H_2} = 0,15(mol)$
$C_{M_{FeSO_4}} = \dfrac{0,15}{0,05} = 3M$
![](https://rs.olm.vn/images/avt/0.png?1311)
a.
2Al+6HCl => 2AlCl3+3H2(1)
Ta có:
mAl=5,4g
=> nAl=0,2mol
=> nHCl=3nAl=0,6mol
mHCl=0,6.36,5=21,9g
b.
mddHCl=21,9/14%=156,43g
=> nAlCl3=nAl=0,2mol và nH2=3/2nAl=0,3mol
=> mAlCl3=12,5
=> mddsau=mddHCl+mAl-mH2 = 156,43+5,4-0,3.2=161,23g
C%muối=(12,5/161,23).100%=7,75%
![](https://rs.olm.vn/images/avt/0.png?1311)
Ta có: \(n_{MgO}=\dfrac{4}{40}=0,1\left(mol\right)\)
PTHH: MgO + 2HCl ---> MgCl2 + H2.
Theo PT: \(n_{MgCl_2}=n_{MgO}=0,1\left(mol\right)\)
=> \(m_{MgCl_2}=0,1.95=9,5\left(g\right)\)
Ta có: \(m_{dd_{MgCl_2}}=4+100=104\left(g\right)\)
=> \(C_{\%_{MgCl_2}}=\dfrac{9,5}{104}.100\%=9,13\%\)
![](https://rs.olm.vn/images/avt/0.png?1311)
ADCT: nCaCO3=m/M=50/100=0,5(mol)
a,PTHH: CaCO3+2CH3COOH-->(CH3COO)2Ca+CO2+H2O
b, Theo pt: 1 mol CaCO3: 2 mol CH3COOH: 1 mol (CH3COOH)2Ca: 1 mol CO2
Theo đb: 0,5 mol CaCO3: x mol CH3COOH: y mol (CH3COOH)2Ca: z mol CO2
-->x=1 mol
-->y=0,5 mol
-->z=0,5 mol -->mCO2=n.M=0,5.44=22(g)
ADCT: mCH3COOH=n.M=1.60=60(g)
ADCT: C%CH3COOH= (mct/mdd).100%=(60/200).100=30(g)
c, ADCT: m(CH3COOH)2Ca=n.M=0,5.120=60(g)
-->mdd(CH3COOH)2Ca sau p/ứ=(50+200)-22=228(g)
ADCT: C%(CH3COOH)2Ca=(mct/mdd).100%=(60/228).100~26,31(%)
Vậy b, C%CH3COOH=30%
c, C%(CH3COOH)2Ca~26,31 %
![](https://rs.olm.vn/images/avt/0.png?1311)
\(n_{Fe_2O_3}=\dfrac{8}{160}=0,05\left(mol\right)\)
PTHH: Fe2O3 + 3H2SO4 --> Fe2(SO4)3 + 3H2O
______0,05------>0,15--------->0,05
=> mH2SO4 = 0,15.98 = 14,7(g)
=> \(C\%\left(H_2SO_4\right)=\dfrac{14,7}{100}.100\%=14,7\%\)
\(C\%\left(Fe_2\left(SO_4\right)_3\right)=\dfrac{0,05.400}{8+100}.100\%=18,52\%\)
PTHH: Fe2(SO4)3 + 6NaOH --> 2Fe(OH)3\(\downarrow\) + 3Na2SO4
________0,05----------------------->0,1
=> mFe(OH)3 = 0,1.107=10,7(g)
\(n_{MgO}=\dfrac{0,8}{40}=0,02\left(mol\right)\)
\(MgO+H_2SO_4\rightarrow MgSO_4+H_2O\)
\(n_{H_2SO_4}=n_{MgO}=0,02\left(mol\right)\)
\(\Rightarrow C\%_{H_2SO_4}=\dfrac{0,02.98}{50}.100\%=3,92\%\)
\(n_{MgO}=\dfrac{0,8}{40}=0,02\left(mol\right)\)
PTHH :
\(MgO+H_2SO_4\rightarrow MgSO_4+H_2O\)
0,02 0,02
\(a,m_{H_2SO_4}=0,02.98=1,96\left(g\right)\)
\(C\%=\dfrac{1,96}{50}.100\%=3,92\%\)