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200ml = 0,2l
\(n_{KOH}=1.0,2=0,2\left(mol\right)\)
Pt : \(2KOH+H_2SO_4\rightarrow K_2SO_4+2H_2O|\)
2 1 1 2
0,2 0,1
\(n_{H2SO4}=\dfrac{0,2.1}{2}=0,1\left(mol\right)\)
⇒ \(m_{H2SO4}=0,1.98=9,8\left(g\right)\)
\(C_{ddH2SO4}=\dfrac{9,8.100}{49}=20\)0/0
Chúc bạn học tốt
a, \(n_{KOH}=0,3.1=0,3\left(mol\right)\)
PT: \(2KOH+H_2SO_4\rightarrow K_2SO_4+2H_2O\)
Theo PT: \(n_{K_2SO_4}=\dfrac{1}{2}n_{KOH}=0,15\left(mol\right)\)
\(\Rightarrow m_{K_2SO_4}=0,15.174=26,1\left(g\right)\)
b, \(C_{M_{K_2SO_4}}=\dfrac{0,3}{0,3+0,2}=0,6\left(M\right)\)
a, \(2NaOH+H_2SO_4\rightarrow Na_2SO_4+2H_2O\)
\(2KOH+H_2SO_4\rightarrow K_2SO_4+2H_2O\)
Ta có: 40nNaOH + 56nKOH = 25,44 (1)
\(n_{H_2SO_4}=\dfrac{1}{2}n_{NaOH}+\dfrac{1}{2}n_{KOH}=0,3.0,9=0,27\left(mol\right)\left(2\right)\)
Từ (1) và (2) \(\Rightarrow\left\{{}\begin{matrix}n_{NaOH}=0,3\left(mol\right)\\n_{KOH}=0,24\left(mol\right)\end{matrix}\right.\)
\(\Rightarrow\left\{{}\begin{matrix}m_{NaOH}=0,3.40=12\left(g\right)\\m_{KOH}=0,24.56=13,44\left(g\right)\end{matrix}\right.\)
b, \(m_{ddH_2SO_4}=300.1,14=342\left(g\right)\)
\(\Rightarrow C\%_{H_2SO_4}=\dfrac{0,27.98}{342}.100\%\approx7,74\%\)
\(n_{Fe}=\dfrac{5,6}{56}=0,1\left(mol\right)\)
PTHH: Fe + H2SO4 → FeSO4 + H2
Mol: 0,1 0,1
\(C\%_{ddH_2SO_4}=\dfrac{0,1.98.100\%}{100}=9,8\%\)
\(n_{Al\left(OH\right)_3}=\dfrac{7,8}{78}=0,1mol\\ 2Al\left(OH\right)_3+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+6H_2O\\ 0,1................0,15.............0,05............0,3\\ C_{\%H_2SO_4}=\dfrac{0,15.98}{300}\cdot100\%=4,9\%\\ C_{\%Al_2\left(SO_4\right)_3}=\dfrac{0,05.342}{7,8+300}\cdot100\%=5,56\%\)
nK2SO3=15.8\158=0.1(mol)
K2SO3+H2SO4→K2SO4+SO2+H2O
0.1...........................0.1..........0.1
VSO2=0.1⋅22.4=2.24(l)
CMK2SO4=0.1\0.2=0.5(M)
a)
$CuO + H_2SO_4 \to CuSO_4 + H_2O$
$n_{H_2SO_4} = n_{CuO} = \dfrac{1,6}{80} = 0,02(mol)$
$C\%_{H_2SO_4} = \dfrac{0,02.98}{100}.100\% = 1,96\%$
b)
$2NaOH + H_2SO_4 \to Na_2SO_4 + 2H_2O$
$n_{NaOH} = 2n_{H_2SO_4} = 0,04(mol)$
$m_{NaOH} = 0,04.40 = 1,6(gam)$
c)
$Cu + 2H_2SO_4 \to CuSO_4 + SO_2 + 2H_2O$
Cu dư nên $n_{SO_2} = \dfrac{1}{2}n_{H_2SO_4} = 0,05(mol)$
$V_{SO_2} = 0,05.22,4 = 1,12(lít)$
PTHH:\(CaO+H_2SO_4\rightarrow CaSO_4+H_2O \)
tl 1 : 1 : 1 : 1 (mol)
br \(\dfrac{1}{7}\) -> \(\dfrac{1}{7}\)
n\(_{CaO}=\dfrac{8}{56}=\dfrac{1}{7}\left(mol\right)\)
Đổi 200ml=0,2l
=>\(C_{MH_2SO_4}=\dfrac{\dfrac{1}{7}}{0,2}=\dfrac{5}{7}\left(M\right)\)
\(n_{CaO}=\dfrac{m}{M}=\dfrac{8}{56}=0,14\left(mol\right)\)
PTHH:\(CaO+H_2SO_4\rightarrow CaSO_4+H_2O\)
0,14 0,14
\(CM=\dfrac{n_{ct}}{V_{dd}}=\dfrac{0,14}{0,2}=0,7\left(M\right)\)
cho 3,2 g cuo tác dụng vừa đủ với dung dịch H2SO4 , 4,9%. Tính nồng độ phần trăm của dung dịch CuSO4
nCuO=0,04 mol
CuO + H2SO4 =>CuSO4 + H2O
0,04 mol=>0,04 mol=>0,04 mol
mH2SO4=0,04.98=3,92 gam
=>m dd H2SO4=3,92/4,9%=80 gam
mCuSO4 sau=0,04.160=6,4 gam
mdd CuSO4=3,2+80=83,2 gam
C% dd CuSO4=6,4/83,2.100%=7,69%
cho \(m_{CuO}=3,2g\Rightarrow n_{CuO}=\frac{3,2}{80}=0,04mol\)
PTHH:
CuO + H2SO4 -> CuSO4 + H2O
0,04mol----------->0,04mol--------->0,04mol
ta có: \(m_{H_2SO_4}=0,04.98=3,92g\)
\(C\%_{d^2H_2SO_{4_{ }}}=4,9\%\)
=. \(m_{d^2H_2SO_4}=\frac{m_{H_2SO_4}.100}{C\%}=\frac{3,92.100}{4,9}=80g\)
áp dụng ĐLBTKL ta có: \(m_{d^2CUSO_4}=m_{CuO}+m_{d^2H_2SO_4}=3,2+80=83,2g\)
\(m_{CuSO_4}=0,04.160=6,4g\)
\(\Rightarrow C\%_{d^2CuSO_4}=\frac{m_{CuSO_4}}{m_{d^2CuSO_4}}.100=\frac{6,4}{83,2}.100=7,69\%\)
200ml = 0,2l
\(n_{KOH}=1.0,2=0,2\left(mol\right)\)
Pt : \(2KOH+H_2SO_4\rightarrow K_2SO_4+2H_2O|\)
2 1 1 2
0,2 0,1
\(n_{H2SO4}=\dfrac{0,2.1}{2}=0,1\left(mol\right)\)
⇒ \(m_{H2SO4}=0,1.98=9,8\left(g\right)\)
\(C_{ddH2SO4}=\dfrac{9,8.100}{49}=20\)0/0
Chúc bạn học tốt