Cho 7,2 gam magie tác dụng với axit HCl dư. Dẫn toàn bộ hidro sinh ra qua hỗn hợp rắn gồm FeO CuO ZnO nung đỏ. Sau phản ứng kết thúc, để nguội, khối lượng hỗn hợp rắn sẽ giảm bao nhiêu gam?( biết các phản ứng xảy ra hoàn toàn)
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
Ta có: \(m_{giảm}=m_{O\left(oxit\right).tham.gia.phản.ứng}\)
=> \(n_O=\dfrac{8}{16}=0,5\left(mol\right)\)
PTHH:
\(Fe_3O_4+4H_2\xrightarrow[]{t^o}3Fe+4H_2O\\ ZnO+H_2\xrightarrow[]{t^o}Zn+H_2O\)
Theo PT: \(n_{H_2}=n_{O\left(oxit\right)}=0,5\left(mol\right)\)
=> VH2 = 0,5.22,4 = 11,2 (l)
`a) SO_3, SO_2, Al_2O_3`
`SO_3 + 2KOH -> K_2SO_4 + H_2O`
`SO_2 + 2KOH -> K_2SO_3 + H_2O`
`Al_2O_3 + 2KOH -> 2KAlO_2 + H_2O`
`b) K_2O, CuO, Al_2O_3,SO_3,Fe_2O_3`
`K_2O + H_2SO_4 -> K_2SO_4 + H_2O`
`SO_3 + H_2SO_4(đặc) -> H_2SO_4.nSO_3`
`Fe_2O_3 + 3H_2SO_4 -> Fe_2(SO_4)_3 + 3H_2O`
`Al_2O_3 + 3H_2SO_4 -> Al_2(SO_4)_3 + 3H_2O`
`c) SO_3, Al_2O_3`
a) \(Fe_2O_3+3H_2SO_4\rightarrow Fe_2\left(SO_4\right)_3+3H_2O\)
b) \(n_{Fe_2O_3}=\dfrac{64}{160}=0,4\left(mol\right)\)
Theo PTHH: \(n_{Fe_2\left(SO_4\right)_3}=n_{Fe_2O_3}=0,4\left(mol\right)\Rightarrow m_{Fe_2\left(SO_4\right)_3}=0,4.400=160\left(g\right)\)
c) Theo PTHH: \(n_{H_2SO_4}=3.n_{Fe_2O_3}=1,2\left(mol\right)\)
=> \(m_{H_2SO_{\text{4}}}=1,2.98=117,6\left(g\right)\Rightarrow C\%_{H_2SO_4}=\dfrac{117,6}{180}.100\%=65,33\%\)
a) \(ZnO+H_2SO_4\rightarrow ZnSO_4+H_2O\)
b) \(n_{H_2SO_4}=0,15.2=0,3\left(mol\right)\)
PTHH: \(ZnO+H_2SO_4\rightarrow ZnSO_4+H_2O\)
0,3<----0,3--------->0,3
=> mZnO = 0,3.81 = 24,3 (g)
c) \(m_{ZnSO_4}=0,3.161=48,3\left(g\right)\)
a)
\(n_{M_xO_y}=\dfrac{3,06}{x.M_M+16y}\left(mol\right)\)
PTHH: \(M_xO_y+2yHNO_3\rightarrow xM\left(NO_3\right)_{\dfrac{2y}{x}}+yH_2O\)
\(n_{M\left(NO_3\right)_{\dfrac{2y}{x}}}=\dfrac{5,22}{M_M+\dfrac{124y}{x}}\left(mol\right)\)
Theo PTHH: \(x.n_{M_xO_y}=n_{M\left(NO_3\right)_{\dfrac{2y}{x}}}\)
=> \(\dfrac{3,06x}{x.M_M+16y}=\dfrac{5,22}{M_M+\dfrac{124y}{x}}\)
=> \(3,06.x.M_M+379,44y=5,22.x.M_M+83,52y\)
=> \(M_M=68,5.\dfrac{2y}{x}\left(g/mol\right)\)
Xét \(\dfrac{2y}{x}=2\) thỏa mãn => MM = 137 (g/mol)
=> M là Ba
b)
Chất rắn không tan sau khi hòa tan cặn vào dd HCl là tạp chất
=> \(\%m_{tạp.chất}=\dfrac{0,012}{7,05}.100\%=0,17\%\)
Ta có: \(m_{BaCO_3}=0,209-0,012=0,197\left(g\right)\Rightarrow n_{BaCO_3}=\dfrac{0,197}{197}=0,001\left(mol\right)\)
PTHH: \(BaO+CO_2\rightarrow BaCO_3\)
0,001<--0,001<--0,001
=> \(\%m_{BaO\left(biến.thành.muối.cacbonat\right)}=\dfrac{0,001.153}{7,05-0,012}.100\%=2,174\%\)
\(m_{tăng}=m_{CO_2}+m_{H_2O}\)
=> \(0,001.44+18.n_{H_2O}=7,184-7,05\)
=> \(n_{H_2O}=0,005\left(mol\right)\)
PTHH: \(BaO+H_2O\rightarrow Ba\left(OH\right)_2\)
0,005<--0,005
=> \(\%m_{BaO\left(bị.hút.ẩm\right)}=\dfrac{0,005.153}{7,05-0,012}.100\%=10,87\%\)
Gọi \(\left\{{}\begin{matrix}n_{K_2CO_3}=a\left(mol\right)\\n_{KCl}=b\left(mol\right)\\n_{KHCO_3}=c\left(mol\right)\end{matrix}\right.\)
=> 138a + 74,5b + 100c = 39,09 (1)
PTHH: \(K_2CO_3+2HCl\rightarrow2KCl+CO_2+H_2O\)
a------->2a------->2a----->a
\(KHCO_3+HCl\rightarrow KCl+CO_2+H_2O\)
c-------->c-------->c------>c
=> \(a+c=\dfrac{6,72}{22,4}=0,3\) (2)
dd sau pư chứa \(\left\{{}\begin{matrix}KCl:2a+b+c\left(mol\right)\\HCl_{dư}:x\left(mol\right)\end{matrix}\right.\)
=> Mỗi phần chứa \(\left\{{}\begin{matrix}KCl:a+0,5b+0,5c\left(mol\right)\\HCl_{dư}:0,5x\left(mol\right)\end{matrix}\right.\)
- Phần 1:
nNaOH = 0,25.0,4 = 0,1 (mol)
PTHH: \(NaOH+HCl\rightarrow NaCl+H_2O\)
0,1---->0,1
=> 0,5x = 0,1
=> x = 0,2
- Phần 2:
\(n_{AgCl}=\dfrac{51,66}{143,5}=0,36\left(mol\right)\)
PTHH: \(KCl+AgNO_3\rightarrow AgCl\downarrow+KNO_3\)
(a+0,5b+0,5c)-------->(a+0,5b+0,5c)
\(HCl+AgNO_3\rightarrow AgCl\downarrow+HNO_3\)
0,1--------------->0,1
=> a+0,5b+0,5c + 0,1 = 0,36
=> a + 0,5b + 0,5c = 0,26 (3)
(1)(2)(3) => a = 0,2 (mol); b = 0,02 (mol); c = 0,1 (mol)
\(\left\{{}\begin{matrix}m_{K_2CO_3}=0,2.138=27,6\left(g\right)\\m_{KCl}=0,02.74,5=1,49\left(g\right)\\m_{KHCO_3}=0,1.100=10\left(mol\right)\end{matrix}\right.\)
nHCl(bđ) = 2a + c + x = 0,7 (mol)
=> mHCl(bd) = 0,7.36,5 = 25,55 (g)
=> \(m_{dd.HCl}=\dfrac{25,55.100}{10,52}\approx242,87\left(g\right)\)
=> \(V_{dd.HCl}=\dfrac{242,87}{1,05}\approx231,3\left(ml\right)\)
Gọi kim loại đó là R
=> CT oxit, muối sunfat là RO, RSO4
Gọi \(\left\{{}\begin{matrix}n_R=a\left(mol\right)\\n_{RO}=b\left(mol\right)\\n_{RSO_4}=c\left(mol\right)\end{matrix}\right.\)
=> \(aM_R+b\left(M_R+16\right)+c\left(M_R+96\right)=14,8\) (1)
\(n_{H_2}=\dfrac{4,48}{22,4}=0,2\left(mol\right);n_{CuSO_4}=0,2.2=0,4\left(mol\right)\)
PTHH:
\(R+H_2SO_4\rightarrow RSO_4+H_2\)
a----------------->a-------->a
\(RO+H_2SO_4\rightarrow RSO_4+H_2O\)
b-------------------->b
\(2NaOH+H_2SO_4\rightarrow Na_2SO_4+2H_2O\\ RSO_4+2NaOH\rightarrow R\left(OH\right)_2\downarrow+Na_2SO_4\)
(a + b + c)------------>(a + b + c)
\(R\left(OH\right)_2\xrightarrow[]{t^o}RO+H_2O\)
(a + b + c)->(a + b + c)
=> a = 0,2 (2)
\(\left(a+b+c\right)\left(M_R+16\right)=14\) (3)
\(R+CuSO_4\rightarrow RSO_4+Cu\downarrow\)
ban đầu 0,2 0,4
p/ứ 0,2--->0,2
sau p/ứ 0 0,2
=> \(0,2.160+\left(0,2+c\right)\left(M_R+96\right)=62\) (4)
(1),(2),(3),(4) => \(\left\{{}\begin{matrix}a=0,2\\b=0,1\\c=0,05\\M_R=24\end{matrix}\right.\)
=> R là Mg
=> Oxit kim loại là MgO
A: O2
B: SO2
C: SO3
D: BaSO3
E: Ba(HSO3)2
\(2KClO_3\underrightarrow{t^o}2KCl+3O_2\)
\(S+O_2\underrightarrow{t^o}SO_2\)
\(2SO_2+O_2\underrightarrow{t^o,V_2O_5}2SO_3\)
\(SO_3+H_2O\rightarrow H_2SO_4\)
\(Cu+2H_2SO_{4\left(đ,n\right)}\rightarrow CuSO_4+SO_2+2H_2O\)
\(SO_2+Ba\left(OH\right)_2\rightarrow BaSO_3\downarrow+H_2O\)
\(BaSO_3+SO_2+H_2O\rightarrow Ba\left(HSO_3\right)_2\)
\(Ba\left(HSO_3\right)_2\underrightarrow{t^o}BaSO_3+SO_2+H_2O\)
Gọi \(\left\{{}\begin{matrix}n_{O_2\left(bđ\right)}=a\left(mol\right)\\n_{SO_2\left(bđ\right)}=b\left(mol\right)\end{matrix}\right.\)
Ta có: \(\dfrac{32a+64b}{a+b}=24.2=48(g/mol)\)
=> a = b
Giả sử a = b = 1 (mol)
=> mkhí sau pư = 1.32 + 1.64 = 96 (g)
Gọi số mol O2 pư là x (mol)
PTHH: \(2SO_2+O_2\underrightarrow{t^o,V_2O_5}2SO_3\)
Bđ 1 1
Pư: 2x<-----x---------->2x
Sau pư: (1-2x) (1-x) 2x
Ta có: \(\dfrac{96}{\left(1-2x\right)+\left(1-x\right)+2x}=30.2=60\left(g/mol\right)\)
=> x = 0,4 (mol)
Sau pư thu được \(\left\{{}\begin{matrix}SO_2:0,2\left(mol\right)\\O_2:0,6\left(mol\right)\\SO_3:0,8\left(mol\right)\end{matrix}\right.\)
=> \(\left\{{}\begin{matrix}\%V_{SO_2}=\dfrac{0,2}{0,2+0,6+0,8}.100\%=12,5\%\\\%V_{O_2}=\dfrac{0,6}{0,2+0,6+0,8}.100\%=37,5\%\\\%V_{SO_3}=\dfrac{0,8}{0,2+0,6+0,8}.100\%=50\%\end{matrix}\right.\)
\(\%O_2\left(pư\right)=\dfrac{0,4}{1}.100\%=40\%\)
\(\%SO_2\left(pư\right)=\dfrac{0,8}{1}.100\%=80\%\)
\(n_{Mg}=\dfrac{7,2}{24}=0,3\left(mol\right)\)
PTHH: \(Mg+2HCl\rightarrow MgCl_2+H_2\) (1)
0,3---------------------------->0,3
\(FeO+H_2\xrightarrow[]{t^o}Fe+H_2O\) (2)
\(CuO+H_2\xrightarrow[]{t^o}Cu+H_2O\) (3)
\(ZnO+H_2\xrightarrow[]{t^o}Zn+H_2O\) (4)
Theo PT (2),(3),(4): \(n_{O\left(pư\right)}=n_{H_2}=0,3\left(mol\right)\)
=> \(m_{giảm}=m_O=0,3.16=4,8\left(g\right)\)
n Mg=0,3 mol
Mg+2HCl->MgCl2+H2
0,3----------------------0,3
->mgiảm=0,3.16=4,6g