Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
PTHH: \(2KMnO_4\underrightarrow{t^o}K_2MnO_4+MnO_2+O_2\uparrow\)
\(4P+5O_2\underrightarrow{t^o}2P_2O_5\)
Ta có: \(\left\{{}\begin{matrix}n_{O_2}=\dfrac{1}{2}\cdot\dfrac{31,6}{158}\cdot50\%=0,05\left(mol\right)\\n_P=\dfrac{24,8}{31}=0,8\left(mol\right)\end{matrix}\right.\)
Xét tỉ lệ: \(\dfrac{0,8}{4}>\dfrac{0,05}{5}\) \(\Rightarrow\) Photpho còn dư, Oxi p/ứ hết
\(\Rightarrow n_{P_2O_5}=0,02\left(mol\right)\) \(\Rightarrow m_{P_2O_5}=0,02\cdot142=2,84\left(g\right)\)
PT: \(2KMnO_4\underrightarrow{t^o}K_2MnO_4+MnO_2+O_2\)
Ta có: \(n_{KMnO_4}=\dfrac{31,6}{158}=0,2\left(mol\right)\)
Theo PT: \(n_{O_2\left(LT\right)}=\dfrac{1}{2}n_{KMnO_4}=0,1\left(mol\right)\)
Mà: H% = 50%
\(\Rightarrow n_{O_2\left(TT\right)}=0,1.50\%=0,05\left(mol\right)\)
Ta có: \(n_P=\dfrac{24,8}{31}=0,8\left(mol\right)\)
PT: \(4P+5O_2\underrightarrow{t^o}2P_2O_5\)
Xét tỉ lệ: \(\dfrac{0,8}{4}>\dfrac{0,05}{5}\), ta được P dư.
Theo PT: \(n_{P_2O_5}=\dfrac{2}{5}n_{O_2}=0,02\left(mol\right)\)
\(\Rightarrow m_{P_2O_5}=0,02.142=2,84\left(g\right)\)
Bạn tham khảo nhé!
\(m_{KClO_3\left(pư\right)}=24.5\cdot0.5=12.25\left(g\right)\)
\(n_{KClO_3}=\dfrac{12.25}{122.5}=0.1\left(mol\right)\)
\(n_{Al}=\dfrac{2.7}{27}=0.1\left(mol\right)\)
\(2KClO_3\underrightarrow{t^0}2KCl+3O_2\)
\(0.1...........................0.15\)
\(4Al+3O_2\underrightarrow{t^0}2Al_2O_3\)
\(4............3\)
\(0.1..........0.15\)
\(LTL:\dfrac{0.1}{4}< \dfrac{0.15}{3}\Rightarrow O_2dư\)
\(m_{Al_2O_3}=0.05\cdot102=5.1\left(g\right)\)
Ta có: \(n_{KMnO_4}=\dfrac{31,6}{158}=0,2\left(mol\right)\)
PT: \(2KMnO_4\underrightarrow{t^o}K_2MnO_4+MnO_2+O_2\)
Theo PT: \(n_{K_2MnO_4}=n_{MnO_2}=n_{O_2}=\dfrac{1}{2}n_{KMnO_4}=0,1\left(mol\right)\)
\(\Rightarrow m_A=m_{K_2MnO_4}+m_{MnO_2}=0,1.197+0,1.87=28,4\left(g\right)\)
Ta có: \(n_{Fe}=\dfrac{11,2}{56}=0,2\left(mol\right)\)
PT: \(3Fe+2O_2\underrightarrow{t^o}Fe_3O_4\)
Xét tỉ lệ: \(\dfrac{0,2}{3}>\dfrac{0,1}{2}\), ta được Fe dư.
Chất rắn B gồm: Fe3O4 và Fe dư.
⇒ mB = mFe3O4 + mFe (dư) = mFe + mO2 = 11,2 + 0,1.32 = 14,4 (g)
\(n_{KMnO_4}=\dfrac{15.8}{158}=0.1\left(mol\right)\)
\(2KMnO_4\underrightarrow{t^0}K_2MnO_4+MnO_2+O_2\)
\(n_{O_2}=\dfrac{0.1}{2}=0.05\left(mol\right)\)
\(V_{O_2}=0.05\cdot22.4=1.12\left(l\right)\)
\(b.\)
\(n_P=\dfrac{6.2}{31}=0.2\left(mol\right)\)
\(4P+5O_2\underrightarrow{t^0}2P_2O_5\)
\(4.........5\)
\(0.2........0.05\)
\(LTL:\dfrac{0.2}{4}>\dfrac{0.05}{5}\Rightarrow Pdư\)
\(m_{P\left(dư\right)}=\left(0.2-0.04\right)\cdot31=4.96\left(g\right)\)
PTHH:2KMnO4--- K2MnO4+MnO2 +O2
ADCT nKmno4=15,8/158=0,1 mol
a, theo pt có nO2/nKmno4= 1/2
nO2=0,05 mol
ADCT V=n*22,4
VO2=0,05*22,4 =1,12 l
b, PTHH: 5O2+4P---2P2O5
ADCTnP=6,2/31=0,2 mol
Theo pt
nO2/5=0,01 bé hơn nP/4=0,05
P dư
theo pt nP(pư)/nO2=4/5
nP(p/ư)=0,04 mol
nP(dư)=0,05-0,04 =0,01 mol
ADCT:m=n*M
mP(dư)=0,01*31=0,31g
a)\(n_{KMnO_4}=\dfrac{31,6}{158}=0,2\left(m\right)\)
\(PTHH:2KMnO_4\underrightarrow{t^o}K_2MnO_4+MnO_2+O_2\)
tỉ lệ :2 1 1 1
số mol :0,2 0,1 0,1 0,1
\(V_{O_2}=0,1.22,4=2,24\left(l\right)\)
b)\(n_{Fe}=\dfrac{11,2}{56}=0,2\left(m\right)\)
\(PTHH:3Fe+2O_2\underrightarrow{ }Fe_3O_4\)
theo phương trình ta có tỉ lệ\(\dfrac{0,2}{3}>\dfrac{0,1}{2}\)=>Fe dư
\(PTHH:3Fe+2O_2\xrightarrow[]{}Fe_3O_4\)
tỉ lệ :3 2 1
số mol :0,15 0,1 0,05
\(m_{Fe_3O_4}=0,05.232=11,6\left(g\right)\)
$n_{KClO_3} = \dfrac{12,25}{122,5} = 0,1(mol)$
$2KClO_3 \xrightarrow{t^o} 2KCl + 3O_2$
Theo PTHH : $n_{O_2} = \dfrac{3}{2}n_{KClO_3} = 0,15(mol)$
$n_P = \dfrac{15,5}{31} = 0,5(mol)$
$4P + 5O_2 \xrightarrow{t^o} 2P_2O_5$
Ta thấy : $n_P : 4 > n_{O_2} : 5$ nên P dư
$n_{P_2O_5} = \dfrac{2}{5}n_{O_2} = 0,06(mol)$
$m_{P_2O_5} = 0,06.142 = 8,52(gam)$
PT: \(2KMnO_4\underrightarrow{t^o}K_2MnO_4+MnO_2+O_2\)
Ta có: \(n_{KMnO_4}=\dfrac{31,6}{158}=0,2\left(mol\right)\)
Theo PT: \(n_{O_2\left(LT\right)}=\dfrac{1}{2}n_{KMnO_4}=0,1\left(mol\right)\)
Mà: H% = 80%
\(\Rightarrow n_{O_2\left(TT\right)}=0,1.80\%=0,08\left(mol\right)\)
\(\Rightarrow V_{O_2}=0,08.22,4=1,792\left(l\right)\)
PT: \(4P+5O_2\underrightarrow{t^o}2P_2O_5\)
Ta có: \(n_P=\dfrac{3,1}{31}=0,1\left(mol\right)\)
Xét tỉ lệ: \(\dfrac{0,1}{4}>\dfrac{0,08}{5}\), ta được P dư.
Theo PT: \(n_{P\left(pư\right)}=\dfrac{4}{5}n_{O_2}=0,064\left(mol\right)\)
\(\Rightarrow n_{P\left(dư\right)}=0,1-0,064=0,036\left(mol\right)\)
\(\Rightarrow m_{P\left(dư\right)}=0,036.31=1,116\left(g\right)\)
Bạn tham khảo nhé!
\(n_P=\dfrac{6,2}{31}=0,2\left(mol\right)\\ n_{O_2}=\dfrac{8,96}{22,4}=0,4\left(mol\right)\\ PTHH:4P+5O_2\underrightarrow{t^o}2P_2O_5\\ LTL:\dfrac{0,2}{4}< \dfrac{0,4}{5}\Rightarrow O_2dư\)
\(n_{O_2\left(pư\right)}=\dfrac{5}{4}n_P=\dfrac{5}{4}.0,2=0,25\left(mol\right)\\ n_{O_2\left(dư\right)}=0,4-0,25=0,15\left(mol\right)\)
\(n_{P_2O_5\left(lt\right)}=\dfrac{1}{2}n_P=\dfrac{1}{2}.0,2=0,1\left(mol\right)\\ m_{P_2O_5\left(lt\right)}=0,1.142=14,2\left(g\right)\\ m_{P_2O_5\left(tt\right)}=0,1.142.80\%=11,36\left(g\right)\)
\(n_{KMnO_4} = \dfrac{31,6}{158} = 0,2(mol) \Rightarrow n_{KMnO_4\ pư} = 0,2.50\% = 0,1(mol)\\ 2KMnO_4 \xrightarrow{t^o} K_2MnO_4 + MnO_2 + O_2\\ n_{O_2} = \dfrac{n_{KMnO_4}}{2} = 0,05(mol)\\ n_P = \dfrac{24,8}{31} = 0,8(mol)\\ 4P + 5O_2 \xrightarrow{t^o} 2P_2O_5\\ \dfrac{n_P}{4} = 0,2 > \dfrac{n_{O_2}}{5} = 0,01 \to P\ dư\\ n_{P_2O_5} = \dfrac{2}{5}n_{O_2} = 0,02(mol)\\ m_{P_2O_5} = 0,02.142 = 2,84(gam)\)