Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a)
\(Mg + H_2SO_4 \to MgSO_4 + H_2\\ n_{H_2} = n_{Mg} = \dfrac{3,6}{24} = 0,15(mol)\\ b)\\ CuO + H_2 \xrightarrow{t^o} Cu + H_2O\\ n_{Cu} = n_{H_2} = 0,15(mol)\\ \Rightarrow m_{Cu} = 0,15.64 = 9,6(gam)\)
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%
a) Fe + H2SO4 --> FeSO4 + H2
b) \(n_{Fe}=\dfrac{5,6}{56}=0,1\left(mol\right)\)
PTHH: Fe + H2SO4 --> FeSO4 + H2
0,1------------------------>0,1
=> VH2 = 0,1.22,4 = 2,24 (l)
c) \(n_{CuO}=\dfrac{12}{80}=0,15\left(mol\right)\)
PTHH: CuO + H2 --to--> Cu + H2O
Xét tỉ lệ: \(\dfrac{0,15}{1}>\dfrac{0,1}{1}\) => CuO dư, H2 hết
PTHH: CuO + H2 --to--> Cu + H2O
0,1<--0,1------->0,1
=> mCuO(dư) = (0,15 - 0,1).80 = 4 (g)
mCu = 0,1.64 = 6,4 (g)
a, PT: \(Fe+H_2SO_4\rightarrow H_2SO_4+H_2\)
b, Ta có: \(n_{Fe}=\dfrac{5,6}{56}=0,1\left(mol\right)\)
Theo PT: \(n_{H_2}=n_{Fe}=0,1\left(mol\right)\)
\(\Rightarrow V_{H_2}=0,1.22,4=2,24\left(l\right)\)
c, Ta có: \(n_{CuO}=\dfrac{12}{80}=0,15\left(mol\right)\)
PT: \(CuO+H_2\underrightarrow{t^o}Cu+H_2O\)
Xét tỉ lệ: \(\dfrac{0,15}{1}>\dfrac{0,1}{1}\), ta được CuO dư.
Theo PT: \(n_{Cu}=n_{CuO\left(pư\right)}=n_{H_2}=0,1\left(mol\right)\)
\(\Rightarrow n_{CuO\left(dư\right)}=0,05\left(mol\right)\Rightarrow m_{CuO\left(dư\right)}=0,05.80=4\left(g\right)\)
\(m_{Cu}=0,1.64=6,4\left(g\right)\)
Bạn tham khảo nhé!
Bài 1.
\(n_{Fe}=\dfrac{5,6}{56}=0,1mol\)
\(Fe+H_2SO_4\rightarrow FeSO_4+H_2\)
0,1 0,1 0,1 0,1
\(V_{H_2}=0,1\cdot22,4=2,24l\)
\(n_{CuO}=\dfrac{12}{80}=0,15mol\)
\(CuO+H_2\rightarrow Cu+H_2O\)
0,15 0,1
\(\Rightarrow CuO\) dư và dư \(\left(0,15-0,1\right)\cdot80=4g\)
Bài 2.
\(n_P=\dfrac{3,1}{31}=0,1mol\)
\(4P+5O_2\underrightarrow{t^o}2P_2O_5\)
0,1 0,125
\(V_{O_2}=0,125\cdot22,4=2,8l\)
\(n_{Zn}=\dfrac{19,5}{65}=0,3mol\)
\(2Zn+O_2\underrightarrow{t^o}2ZnO\)
0,3 0,125 0
0,25 0,125 0,25
0,05 0 0,25
\(\Rightarrow ZnO\) dư và dư \(0,05\cdot81=4,05g\)
Bài 1.
a, \(n_{Fe}=\dfrac{5,6}{56}=0,1\left(mol\right)\)
PTHH: Fe + H2SO4 ---> FeSO4 + H2
Mol: 0,1 0,1
b, \(V_{H_2}=0,1.22,4=2,24\left(l\right)\)
c, \(n_{CuO}=\dfrac{12}{80}=0,15\left(mol\right)\)
Ta có: \(\dfrac{0,15}{1}>\dfrac{0,1}{1}\) ⇒ CuO dư, H2 hết
PTHH: CuO + H2 ---to----> Cu + H2O
Mol: 0,1 0,1
\(m_{CuOdư}=\left(0,15-0,1\right).80=4\left(g\right)\)
a) 2Al + 3H2SO4 --> Al2(SO4)3 + 3H2
b) \(n_{Al}=\dfrac{10,8}{27}=0,4\left(mol\right)\)
PTHH: 2Al + 3H2SO4 --> Al2(SO4)3 + 3H2
0,4--->0,6-------------------->0,6
=> VH2 = 0,6.22,4 = 13,44 (l)
c) \(V_{dd.H_2SO_4}=\dfrac{0,6}{1}=0,6\left(l\right)\)
d) \(n_{Fe_2O_3}=\dfrac{16}{160}=0,1\left(mol\right)\)
PTHH: Fe2O3 + 3H2 --to--> 2Fe + 3H2O
Xét tỉ lệ: \(\dfrac{0,1}{1}< \dfrac{0,6}{3}\) => Fe2O3 hết, H2 dư
PTHH: Fe2O3 + 3H2 --to--> 2Fe + 3H2O
0,1----------------->0,2
=> mFe = 0,2.56 = 11,2 (g)
a, PT: \(Fe+H_2SO_4\rightarrow FeSO_4+H_2\)
b, Ta có: \(n_{Fe}=\dfrac{19,6}{56}=0,35\left(mol\right)\)
Theo PT: \(n_{H_2}=n_{Fe}=0,35\left(mol\right)\)
\(\Rightarrow V_{H_2}=0,35.22,4=7,84\left(l\right)\)
c, Ta có: \(n_{CuO}=\dfrac{12}{80}=0,15\left(mol\right)\)
PT: \(CuO+H_2\underrightarrow{t^o}Cu+H_2O\)
Xét tỉ lệ: \(\dfrac{0,15}{1}< \dfrac{0,35}{1}\), ta được H2 dư.
Theo PT: \(n_{H_2\left(pư\right)}=n_{CuO}=0,15\left(mol\right)\)
\(\Rightarrow n_{H_2\left(dư\right)}=0,35-0,15=0,2\left(mol\right)\)
\(\Rightarrow m_{H_2\left(dư\right)}=0,2.2=0,4\left(g\right)\)
\(n_{Zn}=\dfrac{13}{65}=0,2\left(mol\right)\)
\(PTHH:Zn+H_2SO_4\rightarrow ZnSO_4+H_2\)
(mol)_____0,2____0,2______0,2____0,2__
\(a.V_{H_2}=22,4.0,2=4,48\left(l\right)\)
\(b.m_{ddH_2SO_4}=\dfrac{0,2.98.100}{24,5}=80\left(g\right)\)
\(c.m_{ddspu}=13+80-0,2.2=92,6\left(g\right)\\ \Rightarrow C\%_{ddspu}=\dfrac{0,2.136}{92,6}.100=29,4\left(\%\right)\)
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)