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[Trần Văn Quyết]

1.([Cu(NH3)4](2+) === Cu(2+) + 4NH3) ; K = 10^-12
4.(NH3 + H(+) === NH4(+)) ; Ka^-1 = 10^9.25
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[Cu(NH3)4](2+) + 4H(+) === Cu(2+) + 4NH4(+) ; K = K.Ka^-4 = 10^25

_______[Cu(NH3)4](2+) + 4H(+) === Cu(2+) + 4NH4(+) ; K = 10^25
Co |____1______________?_________0________0
dC|__-0.999__________3.996______0.999____3.996
[] |___10^-3__________h________0.999_____3.996

K = ( 0.999 * 3.996^4 ) / (10^-3*h^4) = 10^25
=> h = 10^-4.898483
Mình làm sai chỗ nào nhỉ?