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\(n_{H_2}=\dfrac{11,2}{22,4}=0,5\left(mol\right)\)
PTHH :
\(2Na+2H_2O\rightarrow2NaOH+H_2\uparrow\)
1 0,5
\(b,m_{NaOH}=1.40=40\left(g\right)\)
\(c,H_2+O_2\underrightarrow{t^o}2H_2O\)
0,5 0,5
\(V_{O_2}=0,5.22,4=11,2\left(l\right)\)
\(V_{kk}=11,2.5=56\left(l\right)\)
a. \(n_{Fe}=\dfrac{33.6}{56}=0,6\left(mol\right)\)
PTHH : Fe + 2HCl -> FeCl2 + H2
0,6 0,6
\(V_{H_2}=0,6.22,4=13,44\left(l\right)\)
b. \(n_{Fe}=\dfrac{80}{56}=\dfrac{10}{7}\left(mol\right)\)
PTHH: Fe2O3 + 3H2 -> 2Fe + 3H2O
0,6 0,4
Ta thấy : \(\dfrac{\dfrac{10}{7}}{3}\) > \(\dfrac{0.6}{3}\) => Fe dư , H2 đủ
\(m_{Fe\left(dư\right)}=\left(\dfrac{\dfrac{10}{7}}{3}-0,4\right).56\approx4,266\left(g\right)\)
a) 2Na+2H2O→2NaOH+H2(1)
2K+2H2O→2KOH+H2(2)
b) nNa=\(\dfrac{4,6}{23}\)=0,2(mol)
Theo PTHH (1): nNa:nH2=2:1
⇒nH2(1)=nNa.12=0,2.12=0,1(mol)
⇒VH2(1)=0,1.22,4=2,24(l)
nK=\(\dfrac{3,9}{39}\)=0,1(mol)
Theo PTHH (2): nK:nH2=2:1
⇒nH2(2)=nK.12=0,1.12=0,05(mol)
⇒VH2(2)=0,05.22,4=1,12(l)
⇒Vh2=2,24+1,12=3,36(l)
c) Dung dịch thu được sau phản ứng làm giấy quỳ tím chuyển đổi thành màu xanh vì nó là dung dịch bazơ.
d)
Fe2O3+3H2-to>2Fe+3H2O
0,15------0,1
n Fe2O3=0,1 mol
=>Fe2O3 dư
=>m Fe=0,1.56=5,6g
\(n_{Zn}=\dfrac{13}{65}=0,2\left(mol\right)\)
\(n_{FeO}=\dfrac{64,8}{72}=0,9\left(mol\right)\)
PTHH: Zn + 2HCl ---> ZnCl2 + H2
0,2------------------------->0,2
=> VH2 = 0,2.22,4 = 4,48 (l)
PTHH: FeO + H2 --to--> Fe + H2O
LTL: 0,9 > 0,2 => FeO dư
Theo pthh: nFe = nH2 = 0,2 (mol)
=> mFe = 0,2.56 =11,2 (g)
\(n_{Fe_2O_3}=\dfrac{14.4}{160}=0.09\left(mol\right)\)
\(Fe_2O_3+3H_2\underrightarrow{^{t^0}}2Fe+3H_2O\)
\(0.09.........0.27...0.18\)
\(V_{H_2}=0.27\cdot22.4=6.048\left(l\right)\)
\(m_{Fe}=0.18\cdot56=10.08\left(g\right)\)
a, PT: \(Zn+2HCl\rightarrow ZnCl_2+H_2\)
b, Ta có: \(n_{Zn}=\dfrac{6,5}{65}=0,1\left(mol\right)\)
Theo PT: \(n_{H_2}=n_{Zn}=0,1\left(mol\right)\Rightarrow V_{H_2}=0,1.22,4=2,24\left(l\right)\)
c, PT: \(Fe_2O_3+3H_2\underrightarrow{t^o}2Fe+3H_2O\)
Theo PT: \(n_{Fe}=\dfrac{2}{3}n_{H_2}=\dfrac{1}{15}\left(mol\right)\Rightarrow m_{Fe}=\dfrac{1}{15}.56=\dfrac{56}{15}\left(g\right)\)
\(n_{Cu}=\dfrac{6,4}{64}=0,1mol\)
\(CuO+H_2\rightarrow\left(t^o\right)Cu+H_2O\)
0,1 0,1 ( mol )
\(\left\{{}\begin{matrix}m_{CuO}=0,1.80=8g\\m_{FeO}=12-8=4g\end{matrix}\right.\)
a)
FeO + H2 --to--> Fe + H2O
CuO + H2 --to--> Cu + H2O
b) \(n_{Cu}=\dfrac{6,4}{64}=0,1\left(mol\right)\)
PTHH: CuO + H2 --to--> Cu + H2O
0,1<--0,1<-----0,1
=> \(m_{FeO}=12-0,1.80=4\left(g\right)\)
=> \(n_{FeO}=\dfrac{4}{72}=\dfrac{1}{18}\left(mol\right)\)
FeO + H2 --to--> Fe + H2O
\(\dfrac{1}{18}\)-->\(\dfrac{1}{18}\)----->\(\dfrac{1}{18}\)
=> \(V_{H_2}=\left(0,1+\dfrac{1}{18}\right).22,4=\dfrac{784}{225}\left(l\right)\)
c) \(m_{Fe}=\dfrac{1}{18}.56=\dfrac{28}{9}\left(g\right)\)
d) \(\left\{{}\begin{matrix}m_{CuO}=0,1.80=8\left(g\right)\\m_{FeO}=4\left(g\right)\end{matrix}\right.\)
a) PTHH:
2Na + 2H2O \(\rightarrow\) 2NaOH +H2
b) nNa = \(\dfrac{m}{M}\) = \(\dfrac{9,2}{23}=0,4\) mol
- PTHH:
2Na + 2H2O \(\rightarrow\) 2NaOH +H2
2mol 1mol
0,4mol ?
- Theo PTHH, ta có:
nH2 = \(\dfrac{0,4.1}{2}=0,2\) mol
VH2 (dktc)= n. 22,4 = 0,2 . 22,4 = 4,48(l)
c)-PTHH:
3H2 + Fe2O3 \(\rightarrow\) 2Fe + 3H2O
3mol 2mol
0,2mol ?
- Theo PTHH, ta có:
nFe = \(\dfrac{0,2.2}{3}=\dfrac{2}{15}\approx0,13\) mol
mFe = \(n.M\) = 0,13 . 56 = 7,28 (g)
a) PTHH: 2Na + 2H2O -> 2NaOH + H2
Ta có: \(n_{Na}=\dfrac{9,2}{23}=0,4\left(mol\right)\)
b) Ta có: \(n_{H_2}=\dfrac{0,4}{2}=0,2\left(mol\right)\)
=> \(V_{H_2\left(đktc\right)}=0,2.22,4=4,48\left(l\right)\)
c) PTHH: 3H2 + Fe2O3 -to-> 2Fe + 3H2O
Ta có: \(n_{H_2}=0,2\left(mol\right)\)
Ta có: \(n_{Fe}=\dfrac{2.0,2}{3}=\dfrac{2}{15}\left(mol\right)\)
=> \(m_{Fe}=56.\dfrac{2}{15}\approx7,467\left(g\right)\)