\(\text{*cho vào nước}\)
\(\text{Ba+2H2O-->Ba(OH)2+H2}\)
\(\text{0.4< --------------------0.4}\)
\(\text{*cho vào NaOH}\)
nH2=0.55
\(\text{Ba+2H2O-->Ba(OH)2+H2}\)
\(\text{0.4--------------------->0.4}\)
nH2 ở phản ứng sau là 0.55-0.4=0.15
\(\text{2Al+ 2NaOH+ 2H2O-->2NaAlO2+ 3H2}\)
\(\text{0.1< ----------------------------------0.15}\)
\(\text{*cho vào HCl dư}\)
nH2=0.6
\(\text{Ba+ 2HCl-->BaCl2+H2}\)
\(\text{0.4------------------>0.4}\)
\(\text{2Al+6HCl-->2AlCl3+3H2}\)
\(\text{0.1------------------->0.15}\)
nH2 sinh ra ở phản ứng sau là 0.6-0.4-0.15=0.05
\(\text{Mg+2HCl-->MgCl2+H2}\)
\(\text{0.05< -----------------0.05}\)
Vậy m=0,4.137+0,1.27+0,05.24=58,7
\(\Rightarrow\left\{{}\begin{matrix}\text{%mBa=0.4*137/58.7=93.35%}\\\text{%mMg=0.05*24/58.7=2.04%}\\\text{%mAl=4,61%}\end{matrix}\right.\)