If a glass plate/slide is held into the luminous part of candle flame we see a circular blackish ring that represents:A.unburnt carbon particlesB.formation of coalC.burnt carbon particlesD.Both burnt carbon particles & formation of coal

The innermost zone of flame of a candle isA Yellow B Blue C Black D White

Subject: ScienceScenario : Have you observed the flame of the candle? Have you noticed three different colour shades in a flame? Do you wonder why there are different colour shades in the flame of the same candle? These are three different zones of flame. The image shows three zones of flame with their names.The innermost zone of flame is also known as the dark zone, the middle zone of flame is also known as the luminous zone and the outermost zone of flame is also known as the non-luminous zone. Wax candle vaporises during burning and so forms flame. Due to the combustion process of these wax vapours, all these three zones of flame have different colours. The table shows the combustion process in different zones of flame. Flame Zone Combustion Processinnermost no combustionmiddle partial combustionoutermost complete combustionQuestion:7 )  Which zone of the flame gets sufficient oxygen for combustion?A)   middle zoneB)    outermost zoneC)    Both the middle and outermost zoneD)    Both the innermost and middle zone

Why do substances burn with or without a flame?Have you ever observed either a coal or a wood fire? If not, the next time you get achance, take close note of what happens when the wood or coal starts to burn. Youhave seen above that a candle or the LPG in the gas stove burns with a flame. However,you will observe the coal or charcoal in an ‘angithi’ sometimes just glows red andgives out heat without a flame. This is because a flame is only produced when gaseoussubstances burn. When wood or charcoal is ignited, the volatile substances presentvapourise and burn with a flame in the beginning.A luminous flame is seen when the atoms of the gaseous substance are heated andstart to glow. The colour produced by each element is a characteristic property ofthat element. Try and heat a copper wire in the flame of a gas stove and observe itscolour. You have seen that incomplete combustion gives soot which is carbon. Onthis basis, what will you attribute the yellow colour of a candle flame to?

The middle zone of a candle flame is also called the zone of ______ combustion.

Which of the following is an example of rapid combustion?A.CandleB.CrackerC.White phosphorusD.Sulphur