Calculate the molecular masses of the following compounds:

(a) Methane, CH4


(b) Ethane, C2 H6


(c) Ethene, C2 H4


(d) Ethyne, C2 H2


(Atomic masses: C = 12 u; H = 1 u)

(a). Molecular mass of methane (CH4) = 12 + 4 = 16 u

(b). Molecular mass of ethane (C2H6) = 2 x 12 + 6 x 1 = 30 u


(c). Molecular mass of ethane (C2H4) = 2 x 12 + 4 x 1 = 28 u


(d). Molecular mass of ethyne (C2H2) = 2 x 12 + 2 x 1 = 26 u


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