Alkynes have the general molecular formula C_nH_2n-2. Thus, when n= 2, the alkyne is C₂H₂ etc. If an alkyne has a molecular mass between 75 and 85, this alkyne is ________.

Question

Quizplus · Accepted Answer

The molecular mass of an alkyne with the formula C_nH_2n-2 is 12n+2(1)-2 = 12n. If the molecular mass is between 75 and 85, then 75 ≤ 12n ≤ 85, which gives 6.25 ≤ n ≤ 7.08. Since n must be an integer, the only possible value is n = 6. Therefore, the alkyne is C₆H₁₀.

Alkynes Have the General Molecular Formula CnH2n-2

Alkynes Have the General Molecular Formula C_nH_2n-2