Tính phần trăm mỗi nguyên tố có trong các hợp chất: Al2O3, MgCl2, Na2S, (NH4)2CO3

Đối với hợp chất Al₂O₃

\(\%Al\hspace{0.278em}=\hspace{0.278em}\frac{KLNT\hspace{0.278em}(Al)\times2\hspace{0.278em}}{KLPT\hspace{0.278em}(Al_2O_3)}\times\hspace{0.278em}100\%=\frac{27\hspace{0.278em}\times\hspace{0.278em}2}{\hspace{0.278em}27\hspace{0.278em}\times\hspace{0.278em}2\hspace{0.278em}+\hspace{0.278em}16\hspace{0.278em}\times\hspace{0.278em}3}\hspace{0.278em}\times\hspace{0.278em}100\%\hspace{0.278em}=\hspace{0.278em}52,94\%\)

%O = 100% - 52,94% = 47,06%

Đối với hợp chất MgCl₂

\(\%Mg\;=\;\frac{KLNT\;(Mg)\times1\;}{KLPT\;(MgCl_2)}\times\;100\%=\frac{24\;\times\;1}{\;24\;\times\;1\;+\;35,5\;\times\;2}\;\times\;100\%\;=\;25,26\%\)

%Cl = 100% - 25,26% = 74,74%

Đối với hợp chất Na₂S

\(\%Na=\;\frac{KLNT\;(Na)\times2\;}{KLPT\;(Na_2S)}\times\;100\%=\frac{23\;\times\;2}{\;23\;\times\;2\;+\;32\;\times\;1}\;\times\;100\%\;=29,49\%\)

%S = 100% - 29,49% = 70,51%

Đối với hợp chất (NH4)2CO3

\(\%N=\;\frac{KLNT\;(N)\times2\;}{KLPT\;({(NH_4)}_2CO_3)}\times\;100\%\\=\frac{14\;\times\;2}{14\;\times\;2\;+1\times4\times2+\;12\;+16\times\;3}\;\times\;100\%\;=29,17\%\)

\(\%H=\;\frac{KLNT\;(H)\times4\times2\;}{KLPT\;({(NH_4)}_2CO_3)}\times\;100\%\\=\frac{1\times4\;\times\;2}{14\;\times\;2\;+1\times4\times2+\;12\;+16\times\;3}\;\times\;100\%\;=8,33\%\)

\(\%C=\;\frac{KLNT\;(C)\times1}{KLPT\;({(NH_4)}_2CO_3)}\times\;100\%\\=\frac{12\;\times1}{14\;\times\;2\;+1\times4\times2+\;12\;+16\times\;3}\;\times\;100\%\;=12,5\%\)

%O = 100% - %N - %H - %C = 100% - 29,17% - 8,33% - 12,5% = 50%

Hợp chất Al2O3:

%Al = 27.2/(27.2+16.3) . 100% ≈ 52,94%

%O = 16.3/(27.2+16.3) . 100% ≈ 47,06%

Hợp chất MgCl₂:

%Mg = 24/(24+35,5.2) . 100% ≈ 25,26%

%Cl = 35,5.2/(24+35,5.2) . 100% ≈ 74,74%

Hợp chất Na₂S:

%Na = 23.2(23.2+32) . 100% ≈ 58.97%

% S = 32/(23.2+32) . 100% ≈ 41,03%

Hợp chất (NH₄)₂CO₃:

%N = 14.2/[(14+1.4).2+12+16.3] . 100% ≈ 29,2%

%H = 1.4.2/[(14+1.4).2+12+16.3] . 100% ≈ 8,3%

%C = 12/[(14+1.4).2+12+16.3] . 100% = 12.5%

%O = 16.3/[(14+1.4).2+12+16.3] . 100% = 50%

Đối với hợp chất Al₂O₃

\(\%Al\hspace{0.278em}=\hspace{0.278em}\frac{KLNT\hspace{0.278em}(Al)\times2\hspace{0.278em}}{KLPT\hspace{0.278em}(Al_2O_3)}\times\hspace{0.278em}100\%=\frac{27\hspace{0.278em}\times\hspace{0.278em}2}{\hspace{0.278em}27\hspace{0.278em}\times\hspace{0.278em}2\hspace{0.278em}+\hspace{0.278em}16\hspace{0.278em}\times\hspace{0.278em}3}\hspace{0.278em}\times\hspace{0.278em}100\%\hspace{0.278em}=\hspace{0.278em}52,94\%\)

%O = 100% - 52,94% = 47,06%

\(\%Al\hspace{0.278em}=\hspace{0.278em}\frac{KLNT\hspace{0.278em}(Al)\times2\hspace{0.278em}}{KLPT\hspace{0.278em}(Al_2O_3)}\times\hspace{0.278em}100\%=\frac{27\hspace{0.278em}\times\hspace{0.278em}2}{\hspace{0.278em}27\hspace{0.278em}\times\hspace{0.278em}2\hspace{0.278em}+\hspace{0.278em}16\hspace{0.278em}\times\hspace{0.278em}3}\hspace{0.278em}\times\hspace{0.278em}100\%\hspace{0.278em}=\hspace{0.278em}52,94\%\)

%O = 100% - 52,94% = 47,06%

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