Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
![](https://rs.olm.vn/images/avt/0.png?1311)
a, PT: \(2Mg+O_2\underrightarrow{t^o}2MgO\)
b, Ta có: \(n_{Mg}=\dfrac{2,4}{24}=0,1\left(mol\right)\)
Theo PT: \(n_{O_2}=\dfrac{1}{2}n_{Mg}=0,05\left(mol\right)\)
\(\Rightarrow V_{O_2}=0,05.22,4=1,12\left(l\right)\)
c, PT: \(2Zn+O_2\underrightarrow{t^o}2ZnO\)
Theo PT: \(n_{ZnO}=2n_{O_2}=0,1\left(mol\right)\)
\(\Rightarrow m_{ZnO}=0,1.81=8,1\left(g\right)\)
Bạn tham khảo nhé!
a. \(2Mg+O_2\rightarrow2MgO\)
b. \(n_{Mg}=\dfrac{2,4}{24}=0,1\left(mol\right)\)
\(\rightarrow n_{O_2}=\dfrac{1}{2}.n_{Mg}=0,05\left(mol\right)\)
\(V_{O_2}=0,05.22,4=1,12\left(l\right)\)
c.
\(2Zn+O_2\rightarrow2ZnO\)
0,1 ...... 0,05 .... 0,1 (mol)
\(\rightarrow m_{ZnO}=0,1.81=8,1\left(g\right)\)
![](https://rs.olm.vn/images/avt/0.png?1311)
a) \(n_{Zn}=\dfrac{6,5}{65}=0,1\left(mol\right)\)
PTHH: Zn + 2HCl --> ZnCl2 + H2
0,1-->0,2------>0,1-->0,1
=> VH2 = 0,1.22,4 = 2,24 (l)
mZnCl2 = 0,1.136 = 13,6 (g)
b) \(C\%_{dd.HCl}=\dfrac{0,2.36,5}{200}.100\%=3,65\%\)
c) \(n_{O_2}=\dfrac{3,36}{22,4}=0,15\left(mol\right)\)
PTHH: 2H2 + O2 --to--> 2H2O
Xét tỉ lệ: \(\dfrac{0,1}{2}< \dfrac{0,15}{1}\) => H2 hết, O2 dư
PTHH: 2H2 + O2 --to--> 2H2O
0,1--------------->0,1
=> mH2O = 0,1.18 = 1,8 (g)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(n_{Al}=\dfrac{5,4}{27}=0,2\left(mol\right)\\ 4Al+3O_2\rightarrow\left(t^o\right)2Al_2O_3\\ n_{O_2}=\dfrac{3}{4}.0,2=0,15\left(mol\right)\\ V_{O_2\left(đktc\right)}=0,15.22,4=3,36\left(l\right)\\ V_{kk\left(đktc\right)}=5.3,36=16,8\left(l\right)\\ b,n_{Al_2O_3}=\dfrac{0,2}{2}=0,1\left(mol\right)\\ m_{Al_2O_3}=0,1.102=10,2\left(g\right)\)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(PTHH:3Fe+2O_2\underrightarrow{t^o}Fe_3O_4\)
\(Áp.dụng.ĐLBTKL,ta.có:m_{Fe}+m_{O_2}=m_{Fe_3O_4}\\ \Rightarrow m_{O_2}=m_{Fe_3O_4}-m_{Fe}=23,2-16,8=6,4\left(g\right)\\ \Rightarrow n_{O_2}=\dfrac{m}{M}=\dfrac{6,4}{32}=0,2\left(mol\right)\\ \Rightarrow V_{O_2}=n.22,4=0,2.22,4=4,48\left(l\right)\)
3Fe+2O2->Fe3O4
nFe3O4=23,2/232=0,1 mol
=>nO2=0,1x2=0,2 mol
VO2=0,2x22,4=4,48 l
![](https://rs.olm.vn/images/avt/0.png?1311)
\(n_K=\dfrac{m}{M}=\dfrac{7,8}{39}=0,2\left(mol\right)\)
\(a,PTHH:4K+O_2\rightarrow2K_2O\)
\(0,2:0,05:0,1\left(mol\right)\)
\(K_2O+H_2O\rightarrow2KOH\)
\(0,1:0,1:0,2\left(mol\right)\)
\(b,V_{O_2}=n.22,4=0,05.22,4=1,12\left(l\right)\)
\(c,m_{KOH}=n.M=0,2.\left(39+16+1\right)=0,2.56=11,2\left(g\right)\)
nK=mM=7,839=0,2(mol)��=��=7,839=0,2(���)
a,PTHH:4K+O2→2K2O�,����:4�+�2→2�2�
0,2:0,05:0,1(mol)0,2:0,05:0,1(���)
K2O+H2O→2KOH�2�+�2�→2���
0,1:0,1:0,2(mol)0,1:0,1:0,2(���)
b,VO2=n.22,4=0,05.22,4=1,12(l)�,��2=�.22,4=0,05.22,4=1,12(�)
c,mKOH=n.M=0,2.(39+16+1)=0,2.56=11,2(g)�,����=�.�=0,2.(39+16+1)=0,2.56=11,2(�)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(n_B=\dfrac{4,48}{22,4}=0,2mol\)
\(C+O_2\underrightarrow{t^o}CO_2\)
\(S+O_2\underrightarrow{t^o}SO_2\)
\(\Rightarrow\Sigma n_B=\Sigma n_{O_2}=0,2mol\)
\(\Rightarrow V_{O_2}=0,2\cdot22,4=4,48l\)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(2Cu+O_2\rightarrow\left(t^o\right)2CuO\\ n_{CuO}=n_{Cu}=\dfrac{6,4}{64}=0,1\left(mol\right);n_{O_2}=\dfrac{0,1}{2}=0,05\left(mol\right)\\ a,V_{O_2\left(đktc\right)}=0,05.22,4=1,12\left(l\right)\\ V_{kk\left(đktc\right)}=\dfrac{100.1,12}{20}=5,6\left(l\right)\\ b,m_{CuO}=0,1.80=8\left(g\right)\\ c,2R+O_2\rightarrow\left(t^o\right)2RO\\ n_R=2.n_{O_2}=2.0,05=0,1\left(mol\right)\\ M_R=\dfrac{2,4}{0,1}=24\left(\dfrac{g}{mol}\right)\\ \Rightarrow R:Magie\left(Mg=24\right)\)
![](https://rs.olm.vn/images/avt/0.png?1311)
2K + O2 → 2K2O
nK2O = \(\dfrac{18,8}{94}\)= 0,2 mol => nKphản ứng = 0,2 mol , nO2phản ứng = 0,1 mol
VO2 = 0,1.22,4 = 2,24 lít . Oxi chiếm 1/5 thể tích không khí => V không khí = 2,24.5 = 11,2 lít
mK = 0,2.39 = 7,8 gam
2K + O2 → 2K2O
Nếu có 3,36 lít Oxi phản ứng với 0,2 mol kali => nO2 = \(\dfrac{3,36}{22,4}\)= 0,15mol
Ta có tỉ lệ \(\dfrac{0,2}{2}< \dfrac{0,15}{1}\)=> Oxi dư , kali hết .
Khối lượng sp thu được vẫn tính theo kali => nK2O = 0,2 mol
<=> mK2O = 0,2.94 = 18,8 gam
![](https://rs.olm.vn/images/avt/0.png?1311)
10.
\(n_{Fe}=\dfrac{16.8}{56}=0.3\left(mol\right)\)
\(4Fe+3O_2\underrightarrow{^{^{t^0}}}2Fe_2O_3\)
\(0.3.....0.225....0.15\)
\(V_{O_2}=0.225\cdot22.4=5.04\left(l\right)\)
\(Fe_2O_3+3H_2SO_4\rightarrow Fe_2\left(SO_4\right)_3+3H_2O\)
\(0.15...........0.45\)
\(m_{H_2SO_4}=0.45\cdot98=44.1\left(g\right)\)
11.
\(n_{Fe_2O_3}=\dfrac{48}{160}=0.3\left(mol\right)\)
\(Fe_2O_3+6HCl\rightarrow2FeCl_3+3H_2O\)
\(0.3...........1.8...........0.6\)
\(m_{FeCl_3}=0.6\cdot162.5=97.5\left(g\right)\)
\(m_{HCl}=1.8\cdot36.5=65.7\left(g\right)\)
Bài 10:
\(a,n_{Fe}=\dfrac{16,8}{56}=0,3(mol)\\ PTHH:4Fe+3O_2\xrightarrow{t^o}2Fe_2O_3\\ Fe_2O_3+3H_2SO_4\to Fe_2(SO_4)_3+3H_2O\\ \Rightarrow n_{O_2}=\dfrac{3}{4}n_{Fe}=0,225(mol)\\ \Rightarrow V_{O_2}=0,225.22,4=5,04(l)\\ b,n_{H_2SO_4}=3n_{Fe_2O_3}=3.\dfrac{1}{2}n_{Fe}=0,45(mol)\\ \Rightarrow m_{H_2SO_4}=0,45.98=44,1(g)\)
Bài 11:
\(a,n_{Fe_2O_3}=\dfrac{48}{160}=0,3(mol)\\ PTHH:Fe_2O_3+6HCl\to 2FeCl_3+3H_2O\\ \Rightarrow n_{FeCl_3}=2n_{Fe_2O_3}=0,6(mol)\\ \Rightarrow m_{FeCl_3}=0,6.162,5=97,5(g)\\ b,n_{HCl}=6n_{Fe_2O_3}=1,8(mol)\\ \Rightarrow m_{HCl}=1,8.36,5=65,7(g)\)
\(n_P=\dfrac{6,2}{31}=0,2mol\\ 4P+5O_2\underrightarrow{t^{^{ }0}}2P_2O_5\\ n_{O_2}=\dfrac{5}{4}n_P=0,25mol\\ V_{O_2}=22,4.0,25=5,6L\\ n_S=\dfrac{3,2}{32}=0,1mol\\ S+O_2\underrightarrow{t^{^{ }0}}SO_2\\ Có:\dfrac{n_S}{1}=0,1< \dfrac{n_{O_2}}{1}=0,25\\ \Rightarrow Tính.theo.S\\ n_{SO_2}=0,1mol\\ m_{SO_2}=0,1.64=6,4g\)