Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a) \(n_{Mg}=\dfrac{4,8}{24}=0,2\left(mol\right)\)
PTHH: Mg + 2HCl --> MgCl2 + H2
0,2--------------------->0,2
=> VH2 = 0,2.22,4 = 4,48 (l)
b) \(n_{CuO}=\dfrac{24}{80}=0,3\left(mol\right)\)
PTHH: CuO + H2 --to--> Cu + H2O
Xét tỉ lệ: \(\dfrac{0,3}{1}>\dfrac{0,2}{1}\) => H2 hết, CuO dư
PTHH: CuO + H2 --to--> Cu + H2O
0,2<--0,2-------->0,2
=> mrắn sau pư = 24 - 0,2.80 + 0,2.64 = 20,8 (g)
c)
PTHH: RO + H2 --to--> R + H2O
0,2------>0,2
=> \(M_R=\dfrac{12,8}{0,2}=64\left(g/mol\right)\)
=> R là Cu
+) \(N_{Mg}\) = \(\dfrac{m}{M}\) = \(\dfrac{4,8}{24}\) = 0,2 mol
a) Mg + HCl -> \(MgCl_2\) + \(H_2\)
0,2 -> 0,2 (mol)
b) +) \(N_{CuO}\text{ }\)= \(\dfrac{m}{M}\) = \(\dfrac{24}{80}\) = 0,3 mol
+) \(H_2\) + CuO -> Cu + \(H_2O\)
+) Ta có: \(\dfrac{N_{H_2}}{1}\)= \(\dfrac{0,2}{1}\) < \(\dfrac{N_{CuO}}{1}\)= \(\dfrac{0,3}{1}\)
=> \(H_2\) hết. Tính toán theo \(N_{H_2}\)
+)\(H_2\) + CuO -> Cu + \(H_2O\)
Ban đầu: 0,2 0,3 0 0 }
P/ứng: 0,2 -> 0,2 -> 0,2 -> 0,2 } mol
Sau p/ư: 0 0,1 0,2 0,2 }
=> \(m_{Cu}\) = 12,8 gam .Thu được 2,8 gam Cu
a, \(n_{H_2}=\dfrac{13,44}{22,4}=0,6\left(mol\right)\)
PT: \(Fe+2HCl\rightarrow FeCl_2+H_2\)
Theo PT: \(n_{HCl}=2n_{H_2}=1,2\left(mol\right)\Rightarrow m_{HCl}=1,2.36,5=43,8\left(g\right)\)
\(n_{Fe}=n_{H_2}=0,6\left(mol\right)\Rightarrow m_{Fe}=0,6.56=33,6\left(g\right)\)
c, \(n_{CuO}=\dfrac{16}{80}=0,2\left(mol\right)\)
PT: \(CuO+H_2\underrightarrow{t^o}Cu+H_2O\)
Xét tỉ lệ: \(\dfrac{0,2}{1}< \dfrac{0,6}{1}\), ta được CuO pư hết.
a, nH2 = V/22,4 = 13,44/22,4 =0.6 (mol)
Fe + 2HCl \(\rightarrow \) FeCl2 + H2
TLM : 1 2 1 1
Đề cho: 0,6<--1,2<----------- 0,6 (mol)
mHCl = n . M = 1,2 . 36,5 = 43,8 (g)
mFe= n . M = 0,6 . 56 =33,6 (g)
c, nCuO = \(\dfrac{16}{80}\)= 0,2 (mol)
CuO + H2 \(\rightarrow \) Cu + H2O
TLM: 1 1 1 1
Vì \(\dfrac{nH_2}{1}\)= 0,6 < \(\dfrac{n_{CuO}}{1}\)= 0.2
=> CuO phản ứng hết.
\(a,n_{Fe_2O_3}=\dfrac{8}{160}=0,05\left(mol\right)\\ PTHH:Fe_2O_3+3H_2\underrightarrow{t^o}2Fe+3H_2O\\ Mol:0,05\rightarrow0,15\rightarrow0,1\\ m_{Fe}=0,1.56=5,6\left(g\right)\\ b,V_{H_2}=0,15.22,4=3,36\left(l\right)\\ c,n_{O_2}=\dfrac{1,12}{22,4}=0,05\left(mol\right)\\ \\ PTHH:3Fe+2O_2\underrightarrow{t^o}Fe_3O_4\\ LTL:\dfrac{0,1}{3}>\dfrac{0,05}{2}\Rightarrow Fe.dư\\ n_{Fe_3O_4}=\dfrac{0,05}{2}=0,025\left(mol\right)\\ m_{Fe_3O_4}=0,025.232=5,8\left(g\right)\)
nFe2O3 = 8 : 160 = 0,05 (mol)
pthh: Fe2O3 + 3H2 -t--> 2Fe + 3H2O
0,05--------0,15----->0,1 (mol)
=> VH2= 0,15 . 22,4 = 3,36 (L)
=> mFe = 0,1 . 56 = 5,6 (g)
nO2 = 1,12 : 22,4 = 0,05 (mol)
pthh : 2H2+ O2 -t-> 2H2O
LTL :
0,15/2 > 0,05/1
=> H2 du
theo pt , nH2O = 2 nO2 = 0,1 (mol)
=> mH2O = 0,1 .18 = 1,8 (g)
`a)PTHH:`
`Zn + 2HCl -> ZnCl_2 + H_2 \uparrow`
`0,1` `0,2` `0,1` `(mol)`
`H_2 + CuO` $\xrightarrow{t^o}$ `Cu + H_2 O`
`0,1` `0,1` `(mol)`
`n_[Zn]=[6,5]/65=0,1(mol)`
`n_[HCl]=[10,95]/[36,5]=0,3(mol)`
Ta có: `[0,1]/1 < [0,3]/2`
`=>HCl` dư
`b)V_[H_2]=0,1.22,4=2,24(l)`
`m_[Cu]=0,1.64=6,4(g)`
a) \(n_{Mg}=\dfrac{2,4}{24}=0,1\left(mol\right)\)
PTHH: Mg + H2SO4 --> MgSO4 + H2
0,1---->0,1------->0,1---->0,1
=> \(m_{dd.H_2SO_4}=\dfrac{0,1.98}{4,9\%}=200\left(g\right)\)
b) mdd sau pư = 2,4 + 200 - 0,1.2 = 202,2 (g)
mMgSO4 = 0,1.120 = 12 (g)
\(C\%_{MgSO_4}=\dfrac{12}{202,2}.100\%=5,9\%\)
c)
\(n_{CuO}=\dfrac{20}{80}=0,25\left(mol\right)\)
PTHH: CuO + H2 --to--> Cu + H2O
Xét tỉ lệ: \(\dfrac{0,25}{1}>\dfrac{0,1}{1}\) => Hiệu suất tính theo H2
\(n_{Cu}=\dfrac{3,2}{64}=0,05\left(mol\right)\)
PTHH: CuO + H2 --to--> Cu + H2O
0,05<-----0,05
=> \(H=\dfrac{0,05}{0,1}.100\%=50\%\)
a, \(n_{Mg}=\dfrac{2,4}{24}=0,1\left(mol\right)\)
PTHH: Mg + H2SO4 ---> MgSO4 + H2
0,1--->0,1---------->0,1-------->0,1
\(m_{dd\left(H_2SO_4\right)}=\dfrac{0,1.98}{4,9\%}=200\left(g\right)\)
b, \(m_{dd\left(sau.pư\right)}=2,4+200-0,2.2=202,2\left(g\right)\)
\(\rightarrow C\%_{MgSO_4}=\dfrac{0,1.120}{202,2}.100\%=5,93\%\)
c, \(n_{CuO}=\dfrac{20}{80}=0,25\left(mol\right)\)
PTHH: CuO + H2 --to--> Cu + H2O
LTL: 0,25 > 0,1 => CuO dư
\(n_{Cu}=\dfrac{3,2}{64}=0,05\left(mol\right)\)
Theo pt: \(n_{H_2}=n_{Cu}=0,05\left(mol\right)\)
=> \(H=\dfrac{0,05}{0,1}.100\%=50\%\)
Phải dùng 4,2 g Fe
Cần 6g sắt (III) oxit tác dụng với H2 dư
Bài 3:
\(n_{H_2}=\dfrac{8,96}{22,4}=0,4\left(mol\right)\)
a, PTHH: Fe3O4 + 4H2 --to--> 3Fe + 4H2O
0,1<------0,4
Zn + 2HCl ---> ZnCl2 + H2
0,4<-------------------------0,4
b, mFe3O4 = 0,1.232 = 23,2 (g)
c, mZn = 0,4.65 = 26 (g)
Bài 4:
\(n_{Zn}=\dfrac{6,5}{65}=0,1\left(mol\right)\)
a, PTHH: Zn + 2HCl ---> ZnCl2 + H2
0,1---->0,2---------------->0,1
b, VH2 = 0,1.22,4 = 2,24 (l)
c, \(C_{M\left(HCl\right)}=\dfrac{0,2}{0,2}=1M\)
`H_2 + CuO` $\xrightarrow{t^o}$ `Cu + H_2 O`
`0,3` `0,3` `(mol)`
`n_[H_2]=[7,437]/[22,4]=0,3(mol)`
`@ m_[Cu]=0,3.64=19,2(g)`
`@Mg + H_2 SO_4 -> MgSO_4 + H_2`
`0,3` `0,3` `(mol)`
`=>m_[H_2 SO_4]=0,3.98=29,4(g)`