It is difficult to burn a heap of green leaves but dry leaves catch fire easily. Explain.

Which zone of a flame does a goldsmith use for melting gold and silver and why?

Can the process of rusting be called combustion? Discuss.

Abida and Ramesh were doing an experiment in which water was to be heated in a beaker. Abida kept the beaker near the wick in the yellow part of the candle flame. Ramesh kept the beaker in the outermost part of the flame. Whose water will get heated in a shorter time?