a)
Gọi công thức chung 2 kim loại là T
\(n_T=\dfrac{8,5}{M_T}\left(mol\right)\)
PTHH: \(2T+2H_2O\rightarrow2TOH+H_2\)
\(\dfrac{8,5}{M_T}\)------------->\(\dfrac{8,5}{M_T}\)
=> \(\dfrac{8,5}{M_T}\left(M_T+17\right)=13,6\)
=> MT = 28,333 (g/mol)
=> 2 kim loại là Na và K
Gọi \(\left\{{}\begin{matrix}n_{Na}=a\left(mol\right)\\n_K=b\left(mol\right)\end{matrix}\right.\)
=> 23a + 39b = 8,5 (1)
PTHH: \(2Na+2H_2O\rightarrow2NaOH+H_2\)
\(2K+2H_2O\rightarrow2KOH+H_2\)
=> \(\left\{{}\begin{matrix}n_{NaOH}=a\left(mol\right)\\n_{KOH}=b\left(mol\right)\end{matrix}\right.\) => 40a + 56b = 13,6 (2)
(1)(2) => a = 0,2 (mol); b = 0,1 (mol)
\(\left\{{}\begin{matrix}m_{Na}=0,2.23=4,6\left(g\right)\\m_K=0,1.39=3,9\left(g\right)\end{matrix}\right.\)
b) \(n_{H_2}=0,5a+0,5b=0,15\left(mol\right)\)
=> V = 0,15.22,4 = 3,36 (l)
\(m_{H_2O}=100.1=100\left(g\right)\)
mY = 8,5 + 100 - 0,15.2 = 108,2 (g)