Study the experimental set up of apparatus shown below.
![Studying experimental set up of an apparatus](https://www.easyelimu.com/images/form_4_past_papers/Term_3_2021/Mocks_/Chemistry/Studying_experimental_set_up_of_an_apparatus.JPG)
- State the observation made in the combustion tube as the experiment progressed.
- Using an equation, explain the change that occurred in the conical flask after a long time.
- Why was the gas burned at point x?