Notice in each case that the molecule is effectively twisted on its long axis. The twist is what makes it chiral, by eliminating any plane of symmetry.
| Dimethylallene | Dichlorospiroheptane |
|---|---|
| Dibromobiphenyl | trans-Cyclooctene |
The IUPAC rules for designating absolute configuration include rules that apply to compounds like these. You are not responsible for these, but if you're curious, you can check those rules HERE.