The relative density of alkane vapor in air is 2.414. deduce the molecular formula of the alkene.

Let’s execute the solution:
By the condition of the task, we write the data:
1. Given: CxNu – hydrocarbon, alkene;
D (air) = 2.414;
M (air) = 29 g / mol;
Determine: molecular formula.
2. Determine the molecular weight:
M (CxHy) = D (air) * M (air) = 2.14 * 29 = 70 g / mol.
3. Let us establish the formula based on calculations according to the general formula for alkenes:
CnH2n = 70;
12n + 2 = 70;
12n = 68;
n = 5.6;
C5H10;
Checking: M (C5H10) = 5 * 12 + 10 = 70 g / mol.
Answer: pentene – C5H10.