Molecular formula of an alkene if its molecular weight is 70 g / mol

Let’s execute the solution:
1. Let’s write down the data on the condition of the problem:
Given: СnH2n – alkene;
M (CxHy) = 70 g / mol;
Determine the formula for organic matter.
2. We make calculations:
M (CnH2n) = 70 g / mol;
12n + 2 = 70;
12n = 68;
n = 5.6;
C5H10;
Verification: M (C5H10) = 12 * 5 + 1 * 10 = 70 g / mol.
Answer: C5H10 – pentene.