дано
W(C) = 37. 2% = 0. 37,2
W(H) = 7. 8% = 0. 078
W(CL) = 54. 9% = 0. 549
D(возд) = 2. 22
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CxHyCLz - ?
определяем молекулярную массу вещества
M(CxHyCLz) = D(возд) * 29 = 2. 22*29 = 64. 38 g/mol
CxHyCLz / M(CxHyCLz) = W(C) / Ar(C) : WH) / Ar(H) : W(CL) / Ar(CL)
CxHYCLz / 64. 38 = 0. 37. 2 / 12 : 0. 078 / 1 : 0. 549 / 35. 5
CxHyCLz = 2 : 5 : 1
C2H5CL
C2H5CL