For a complete combustion, $0.100$ mol of propan-1-ol is burnt in $12.0~\text{dm}^3$ of oxygen, with both volumes measured at room conditions. What is the volume of the gas mixture at the end, measured at room conditions?
- A$7.20~ ext{dm}^3$
- B$8.40~ ext{dm}^3$
- C$16.80~ ext{dm}^3$
- D$18.00~ ext{dm}^3$