The coal does not vaporise on heating hence, it does not give out a ____ while burning.

Options

A. Combustion
B. Flame
C. Heating
D. Burning

Answer

To solve the question, we need to understand the properties of coal when it is heated and how it compares to other substances that do vaporize.

1. **Understanding Coal**: Coal is a solid fossil fuel that primarily consists of carbon. When heated, it does not turn into gas (vaporize) like some other substances do.

2. **Combustion Process**: During combustion, substances that vaporize can produce a flame because the vaporized gases ignite. This is typical for substances like wood or gasoline.

3. **Coal's Behavior on Heating**: When coal is heated, it undergoes a process called pyrolysis, where it decomposes into solid residues and gases, but it does not produce a flame because it does not vaporize.

4. **Conclusion**: Since coal does not vaporize when heated, it does not produce a flame while burning. Therefore, the blank in the question can be filled with the word "flame".

Final Answer: The coal does not vaporize on heating hence, it does not give out a **flame** while burning.