Xravi took three substances - p , q and r and burnt them one by one. he noted down his observations as given below : 1. substance p burns quickly producing heat and light. 2. substance q burns quickly producing heat , light and sound. 3. substance r burns in room temperature on it's own. a) from the above observations, identify the type of combustion in each case. b) what could the substances p.q and r possibly be?

Xravi took three substances - p , q and r and burnt them one by one. h

1.	Xravi took three substances - p , q and r and burnt them one by one. he noted down his observations as given below : 1. substance p burns quickly producing heat and light. 2. substance q burns quickly producing heat , light and sound. 3. substance r burns in room temperature on it's own. a) from the above observations, identify the type of combustion in each case. b) what could the substances p.q and r possibly be?
Answer» I don't know the 1 and 2 but 3 the substance is PHOSPHORUS and the combustion is SPONTANEOUS combustion