1)
дано
PH3
C3H8
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D(H2)-?
D(O2)-?
D(возд)-?
M(PH3) = 34 g/mol
D(PH3/H2) = 34 / 2 = 17
D(PH3 / O2) = 34 / 32 = 1.0625
D(PH3/возд) = 34 / 29 = 1.172
M(C3H8) = 44 g/mol
D(C3H8/H2) = 44 / 2 = 22
D(C3H8/O2) = 44 / 32 = 1.375
D(C3H8/ возд) = 44 / 29 = 1.517
2)
дано
D(H2) = 32
-------------------
D(O2)-?
M(г) = D(H2) * 2 = 32 * 2 = 64 g/mol
D(O2) = M(г) / M(O2) = 64 / 32 = 2
ответ : 2