Why does paper burn with a yellow flame ?
A yellow flame comes about when there is insufficient supply of oxygen. It is a luminous flame. In this case the hydrocarbons do not burn completely, the temperature of the flame is lower than that of the blue flame. The yellow flame also leaves behind a black soot or residue.
What are combustible and non-combustible substances ? Explain with examples.
Why is a match stick rubbed against a rough surface to light it ?
What is supposed to be the cause of global warming ?
Goldsmiths blow the outermost zone of a flame with a metallic blow pipe for melting gold and silver. Why do they use the outermost zone of the flame ?
