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\(n_{SO_2}=\dfrac{7.84}{22.4}=0.07\left(mol\right)\)
\(2SO_2+O_2\underrightarrow{^{t^0}}2SO_3\)
\(0.07.............0.07\)
\(m_{dd_{H_2SO_4}}=57.2\cdot1.5=85.8\left(g\right)\)
\(m_{H_2SO_4}=85.8\cdot60\%=51.48\left(g\right)\)
\(SO_3+H_2O\rightarrow H_2SO_4\)
\(0.07..................0.07\)
\(m_{dd}=0.07\cdot80+85.8=91.4\left(g\right)\)
\(\sum n_{H_2SO_4}=0.07\cdot98+51.48=58.34\left(g\right)\)
\(C\%_{H_2SO_4}=\dfrac{58.34}{91.4}\cdot100\%=63.8\%\)
mdd H2SO4 = 57.2 * 1.5 = 85.8 (g)
mH2SO4 = 85.8 * 60/100 = 51.48 (g)
nSO3 = 3.36/22.4 = 0.15 (mol)
SO3 + H2O => H2SO4
0.15......................0.15
mH2SO4 (tổng) = 0.15*98 + 51.48 = 66.18 (g)
mdd sau phản ứng = 0.15*80 + 85.8 = 97.8 (g)
C% H2SO4 = 66.18 / 97.8 * 100% = 67.66%
a)
$Fe + 2HCl \to FeCl_2 + H_2$
n H2 = n Fe = 11,2/56 = 0,2(mol)
V H2 = 0,2.22,4 = 4,48(lít)
b)
n HCl = 2n Fe = 0,2.2 = 0,4(mol)
=> CM HCl = 0,4/0,4 = 1M
c)
$CuO + H_2 \xrightarrow{t^o} Cu + H_2O$
Ta thấy :
n CuO = 64/80 = 0,8 > n H2 = 0,2 nên CuO dư
Theo PTHH :
n CuO pư = n Cu = n H2 = 0,2(mol)
n Cu dư = 0,8 - 0,2 = 0,6(mol)
Vậy :
%m Cu = 0,2.64/(0,2.64 + 0,6.80) .100% = 21,05%
%m CuO = 100% -21,05% = 78,95%
Bài 5:
Ta có: \(n_P=\dfrac{6,2}{31}=0,2\left(mol\right)\)
a, PT: \(4P+5O_2\underrightarrow{t^o}2P_2O_5\)
_____0,2__0,25__0,1 (mol)
b, VO2 = 0,25.22,4 = 5,6 (l)
c, PT: \(P_2O_5+3H_2O\rightarrow2H_3PO_4\)
______0,1______________0,2 (mol)
\(\Rightarrow m_{H_3PO_4}=0,2.98=19,6\left(g\right)\)
\(\Rightarrow C\%_{H_3PO_4}=\dfrac{19,6}{120}.100\%\approx16,33\text{ }\%\)
Bạn tham khảo nhé!
\(n_{Na_2CO_3}=\dfrac{10,6}{106}=0,1\left(mol\right)\\ \rightarrow C_{M\left(Na_2CO_3\right)}=\dfrac{0,1}{0,2}=0,5M\)
Ta có: \(C\%=\dfrac{C_M.M}{10.D}\)
\(\rightarrow C\%=\dfrac{0,5.106}{10.1,05}=5,05\%\)
Câu 5. a) \(SO_2+\dfrac{1}{2}O_2-^{t^o,V_2O_5}\rightarrow SO_3\)
\(n_{SO_3}=n_{SO_2}=0,1\left(mol\right)\)
\(SO_3+H_2O\rightarrow H_2SO_4\)
\(n_{H_2SO_4}=n_{SO_3}=0,1\left(mol\right)\)
=> \(CM_{H_2SO_4}=\dfrac{0,1}{0,2}=0,5M\)
b) \(n_{Zn}=0,05\left(mol\right)\)
\(Zn+H_2SO_4\rightarrow ZnSO_4+H_2\)
Lập tỉ lệ : \(\dfrac{0,05}{1}< \dfrac{0,1}{1}\)=> Sau phản ứng H2SO4 dư
=> \(m_{H_2SO_4\left(dư\right)}=\left(0,1-0,05\right).98=4,9\left(g\right)\)
Câu 5 . \(n_{Al_2O_3}=0,2\left(mol\right);n_{H_2SO_4}=0,8\left(mol\right)\)
\(Al_2O_3+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2O\)
Lập tỉ lệ: \(\dfrac{0,2}{1}< \dfrac{0,8}{3}\) => Sau phản ứng H2SO4 dư
\(m_{H_2SO_4}=\left(0,8-0,2.3\right).98=19,6\left(g\right)\)
b)\(n_{Al_2\left(SO_4\right)_3}=n_{Al_2O_3}=0,2\left(mol\right)\)
\(m_{Al_2\left(SO_4\right)_3}=0,2.342=68,4\left(g\right)\)
a) \(n_{Fe}=\dfrac{1,12}{56}=0,02\left(mol\right)\)
PTHH: Fe + H2SO4 ---> FeSO4 + H2
0,02->0,02------------------>0,02
b) \(V_{H_2}=0,02.22,4=0,448\left(l\right)\)
c) \(C\%_{H_2SO_4}=\dfrac{0,02.98}{100}.100\%=1,96\%\)
d) \(n_{CuO}=\dfrac{0,8}{80}=0,01\left(mol\right)\)
PTHH: CuO + H2 --to--> Cu + H2O
LTL: 0,01 < 0,02 => H2 dư
Theo pthh: nCu = nCuO = 0,01 (mol)
=> mCu = 0,01.64 = 0,64 (g)
$2SO_2 + O_2 \xrightarrow{t^o,xt} 2SO_3$
n SO3 = n SO2 = 7,84/22,4= 0,35(mol)
$SO_3 + H_2O \to H_2SO_4$
m dd H2SO4 60% = 57,2.1,5 = 85,8(gam)
Sau khi pha :
m H2SO4 = 85,8.60% + 0,35.98 = 85,78(gam)
m dd = 85,8 + 0,35.80 = 113,8(gam)
C% H2SO4 = 85,78/113,8 .100% = 75,38%