Nhờ mn giải ạ,đang càn gâppp ạ

Đáp án:

\(a)m_{hh}^{} = 20,25 + 8,16 = 28,41\;{\text{g}}\)

\(\% ZnO = \frac{{20,25}}{{28,41}}.100 = 71,27\% \)

\(\% Al_2^{}O_3^{} = 100 - 71,27 = 28,73\% \)

\(b)\)

\(n_{ZnO}^{} = 0,25\;{\text{mol}} \to n_{Zn}^{} = 0,25\;{\text{mol}}\)

\(n_{Al_2^{}O_3^{}}^{} = \frac{{8,16}}{{102}} = 0,08\;{\text{mol}} \to n_{Al}^{} = 0,08.2 = 0,16\;{\text{mol}}\)

\(m_{Zn}^{} = 0,25.65 = 16,25\;g\)

\(m_{Al}^{} = 0,16.27 = 4,32{\text{ g}}\)