Ответ:

1) дано

W(C) = 87 . 5 % = 0.875

M(CxHy) = 96 g/mol

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CxHy - ?

W(H) = 100% - 87.5 = 12.5 % = 0.125

C: H / M(CxHy) = W(C) / Ar(C)  : W(H) / Ar(H)

C :  H  =  7 : 12

C7H12  

ответ  C7H12

2)

дано

W(N) = 38.7%

W(H) = 45.15%

W(O) = 16.15%

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NxHyOz - ?

W(C) = 38.7%     m(C) = 38.7 g      M(C) = 12 g/mol

W(N) = 45.15%    m(N) = 45.15 g     M(N) = 14 g/mol

W(H) = 16.15%     m(H) = 16.15 g      M(H) = 1 g/mol

n(C) = 38.7 / 12 = 3.225 mol

n(N) = 45.15 / 14= 3.225 mol

n(H) = 16.15 / 1 = 16,15 mol

n(C) : n(N) ; n(H) = 3.225 : 3.225 : 16.15 =  1 : 1 : 5

CNH5 == > CH2NH3

ответ CH2NH3

3)

дано

W(H) = 14.3%

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CxHy - ?

W(C) = 100% - 14.3 = 85,7%

n(C) : n(H) = 85.7 / 12 : 14.3 / 1 = 7 : 14

C7H14

овет C7H14

Объяснение: