Đáp án:
Bạn tham khảo lời giải ở dưới nhé!!!
Giải thích các bước giải:
Câu 1:
\(\begin{array}{l}
NaN{O_3}\\
M = 85\\
\% Na = \dfrac{{23}}{{85}} \times 100\% = 27,06\% \\
\% N = \dfrac{{14}}{{85}} \times 100\% = 16,47\% \\
\% O = \dfrac{{16 \times 3}}{{85}} \times 100\% = 56,47\% \\
{K_2}C{O_3}\\
M = 138\\
\% K = \dfrac{{39 \times 2}}{{138}} \times 100\% = 56,52\% \\
\% C = \dfrac{{12}}{{138}} \times 100\% = 8,7\% \\
\% O = \dfrac{{16 \times 3}}{{138}} \times 100\% = 34,78\% \\
Al{(OH)_3}\\
M = 78\\
\% Al = \dfrac{{27}}{{78}} \times 100\% = 34,62\% \\
\% O = \dfrac{{16 \times 3}}{{78}} \times 100\% = 61,53\% \\
\% H = \dfrac{3}{{78}} \times 100\% = 3,85\% \\
S{O_2}\\
M = 64\\
\% S = \dfrac{{32}}{{64}} \times 100\% = 50\% \\
\% O = \dfrac{{16 \times 2}}{{64}} \times 100\% = 50\% \\
S{O_3}\\
M = 80\\
\% S = \dfrac{{32}}{{80}} \times 100\% = 40\% \\
\% O = \dfrac{{16 \times 3}}{{80}} \times 100\% = 60\% \\
F{e_2}{O_3}\\
M = 160\\
\% Fe = \dfrac{{56 \times 2}}{{160}} \times 100\% = 70\% \\
\% O = \dfrac{{16 \times 3}}{{160}} \times 100\% = 30\%
\end{array}\)
Câu 2:
Gọi hợp chất có công thức là: \({X_2}{O_5}\)
\(\begin{array}{l}
\% X = \dfrac{{2X}}{{2X + 16 \times 5}} \times 100 = 43,67\% \\
\to X = 31\\
\to {P_2}{O_5}
\end{array}\)
Câu 3:
\(\begin{array}{l}
\% O = 100\% - 15,79\% - 28,07\% = 56,14\% \\
{m_{Al}} = \dfrac{{15,79 \times 342}}{{100}} = 54g\\
\to {n_{Al}} = 2mol\\
{m_S} = \dfrac{{28,07 \times 342}}{{100}} = 96g\\
\to {n_S} = 3mol\\
{m_O} = \dfrac{{56,14 \times 342}}{{100}} = 192g\\
\to {n_O} = 12mol\\
\to {n_{Al}}:{n_S}:{n_O} = 2:3:12\\
\to A{l_2}{(S{O_4})_3}
\end{array}\)
