Why is flame seen when substances burn?Can susbtances burn without flame?What is petrol?What is vinegar?

Question

please give answer in datail to all the four questions.

Is some BIOTECHNOLOGY used in them?

Answer 1

Vinegar is acetic acid -- CH3-CH-OOH
Petrol is a bunch of Alkanes, from pentane up to octane.
Flame is the glow of the gases which have been heated so much that they are radiating light. If you get anything hot enough, eg lava, steel, carbon, any of the metals, glass etc-it will glow.
Substances can burn without flame.

Answer 2

To add to what others have already said, a transpiration burner is one in which gas can be used to burn and produce heat for a home, for example, without visible flame. They are made of a sort of porous ceramic, through which the gas filters, then is ignited at the surface, just where it emerges.

Answer 3

Combustion is an exothermic reaction.
Meaning that it gives out heat when there is a chemical reaction.

Answer 4

Why is flame seen when substances burn?
A flame is the product of a highly exothermic reaction (for example ,combustion) a self-sustaining oxidation reaction, or nuclear fusion in the sun. In other words, a flame could be said to be the visible part of a fire.

The color and temperature of the flame are dependent on the type of fuel involved in the combustion. For example: when a lighter is held to a candle. This applied heat causes the fuel molecules to evaporate, in this state they can then react with oxygen, giving off enough heat in the exothermic reaction to sustain a consistent flame. The resulting increases in temperature tear apart some of the fuel molecules, forming various incomplete combustion products and free radicals. Sufficient energy in the flame will excite the electrons in these products, which results in the emission of visible light. As the combustion temperature increases, so does the energy of the electromagnetic radiation given off by the flame. This is why the hottest visible flame is in the blue/violet region of the visible spectrum.

Can susbtances burn without flame?
Combustion or burning is a complex sequence of chemical reactions between a fuel and an oxidant accompanied by the production of heat or both heat and light in the form of either a glow or flames.

So substances can burn with heat only and no flame.

What is petrol?
Gasoline, also called petrol, is a petroleum-derived liquid mixture consisting primarily of hydrocarbons and enhanced with benzenes to increase octane ratings, used as fuel in internal combustion engines.

Many Commonwealth countries use the term petrol (abbreviated from petroleum spirit). The term gasoline is commonly used in North America. The word is commonly shortened in colloquial usage to "gas" (see other meanings). The term mogas, short for motor gasoline, for use in cars is used to distinguish it from avgas, aviation gasoline used in aircraft. This should be distinguished in usage from genuinely gaseous fuels used in internal combustion engines such as LPG.

What is vinegar?
Vinegar is a sour-tasting liquid made from the oxidation of ethanol in wine, cider, beer, fermented fruit juice, or nearly any other liquid containing alcohol. It can also be made by certain bacteria operating on sugar-water solutions directly, without intermediary conversion to ethanol (see acetic acid). Commercially available vinegar usually has a pH of about 2.4.

The word Vinegar comes from the Old French vin aigre, meaning "sour wine."

Is some BIOTECHNOLOGY used in them?
Biotechnology generally refers to the use of microorganisms to produce certain chemical compounds. Long before the term "biotechnology" was coined for the process of using living organisms to produce improved commodities, people were utilizing living micro-organisms to produce valuable products.
You could say that Biotechnology is used for all of these products:
Proving bread with leaven prehistoric period
Fermentation of juices to alcoholic beverages prehistoric period
Knowledge of vinegar formation from fermented juices prehistoric period
Cultivation of vine before 2000 BC
Manufacture of beer in Babylonia and Egypt 3rd century BC
Wine growing promoted by Roman Emperor Marcus Aurelius Probus 3rd century AD
Production of spirits of wine (ethanol) 1150
Vinegar manufacturing industry 14th century
Discovery of the fermentation properties of yeast by Erxleben 1818
Description of lactic acid fermentation by Pasteur 1857
Detection of fermentation enzymes in yeast by Buchner 1897
Discovery of penicillin by Fleming 1928/29
Discovery of many other antibiotics from about 1945