Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
\(a/2Al+3H_2SO_4\xrightarrow[]{}Al_2\left(SO_4\right)_3+3H_2\)
\(b/30ml=0,03l\\ n_{H_2SO_4}=0,5.0,03=0,0015\left(mol\right)\\ n_{Al}=\dfrac{0,0015.2}{3}=0,001\left(mol\right)\\ m_{Al}=0,001.27=0,027\left(g\right)\\ n_{Al_2\left(SO_4\right)_3}=\dfrac{0,0015}{2}=0,00075\left(mol\right)\\ m_{Al_2\left(SO_4\right)_3}=0,00075.342=0,2565\left(g\right)\)
\(c/n_{H_2}=\dfrac{0,0015.3}{3}=0,0015\left(mol\right)\\ V_{H_2}=0,0015.24,79=0,037185\left(l\right)\)
\(a.2Al+3H_2SO_4->Al_2\left(SO_4\right)_3+3H_2\\ b.n_{Al}=1,5.0,5.0,03=0,0375mol\\ m_{Al}=0,0375.27=1,0125g\\ m_{Al_2\left(SO_4\right)_3}=342\cdot\dfrac{1}{3}\cdot0,03\cdot0,5=1,71g\\V_{H_2}=24,79.0,5.0,03=0,37185L\)
Oxit kim loại : R2On
\(\%R = \dfrac{2R}{2R + 16n}.100\% = 60\%\\ \Rightarrow R = 12n\)
Với n = 2 thì R = 24(Magie)
Vậy oxit là MgO
\(MgO+ H_2SO_4 \to MgSO_4 + H_2O\\ n_{MgSO_4} = n_{H_2SO_4} = n_{MgO} = \dfrac{20}{40} = 0,5(mol)\\ \Rightarrow m_{dd\ H_2SO_4} =\dfrac{0,5.98}{10\%} = 490(gam)\\ m_{dd\ sau\ pư} = 20 + 490 = 510(gam)\\ \Rightarrow C\%_{MgSO_4} = \dfrac{0,5.120}{510}.100\% = 11,76\%\)
\(n_{Al}=\dfrac{2,7}{27}=0,1mol\\ a.2Al+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2\)
0,1 0,15 0,05 0,15
\(b.V_{H_2}=0,15.24,79=3,7185l\\ c.m_{Al_2\left(SO_4\right)_3}=0,05.342=17,1g\\ d.C_{M_{H_2SO_4}}=\dfrac{0,15}{0,4}=0,375M\)
\(m_{H_2SO_4}=\dfrac{200\cdot9,8\%}{100\%}=19,6\left(g\right)\\ n_{H_2SO_4}=\dfrac{19,6}{98}=0,2\left(mol\right)\\ PTHH:2KOH+H_2SO_4\rightarrow K_2SO_4+2H_2O\\ \Rightarrow n_{KOH}=2n_{H_2SO_4}=0,4\left(mol\right)\\ \Rightarrow m_{KOH}=0,4\cdot\left(39+16+1\right)=22,4\left(g\right)\)
\(n_{HCl}=\dfrac{200\cdot7.3\%}{36.5}=0.4\left(mol\right)\)
\(Ba\left(OH\right)_2+2HCl\rightarrow BaCl_2+2H_2O\)
\(0.2..................0.4\)
\(m_{Ba\left(OH\right)_2}=0.2\cdot171=34.2\left(g\right)\)
Bạn ơi cho mình hỏi sao nHCl=mdd.C%/M vậy bạn? Cái này là làm gộp đúng không ạ? Nếu làm chậm thì bước đấy làm thế nào vậy ạ?
\(n_{XCl_3}=\dfrac{a}{M_X+106,5}\left(mol\right)\)
PTHH: 2X + 6HCl --> 2XCl3 + 3H2
=> \(n_X=\dfrac{a}{M_X+106,5}\left(mol\right)\)
\(n_{X_2\left(SO_4\right)_3}=\dfrac{b}{2.M_X+288}\left(mol\right)\)
PTHH: 2X + 3H2SO4 --> X2(SO4)3 + 3H2
=> \(n_X=\dfrac{b}{M_X+144}\left(mol\right)\)
nH2SO4 = 49/98 = 0.5 (mol)
CMH2SO4 = 0.5/0.15 = 3.3 (M)
Zn + H2SO4 => ZnSO4 + H2
...........0.5.............0.5.........0.5
VH2 = 0.5 * 22.4 = 11.2 (l)
CMZnSO4 = 0.5 / 0.15 = 10/3 (M)
C%ZnSO4 = CM*M / 10D = 10/3 * 161 / 10 * 1.25 = 42.9 %
\(n_{H_2SO_4}=0,15.1=0,15\left(mol\right)\)
PT: \(Al_2O_3+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2O\)
_______________0,15______0,05 (mol)
\(\Rightarrow m_{Al_2\left(SO_4\right)_3}=0,05.342=17,1\left(g\right)\)