When you put a fresh piece of wood or paper on a hot fire, the smoke you see is volatile hydrocarbons evaporating from the wood. They start vaporizing at a temperature of about 300 degrees F. If the temperature gets high enough, these compounds burst into flame. Once they start burning, there is no smoke because the hydrocarbons are turned into carbon dioxide and water (both invisible) when they burn. What is that temperature in Celsius, to the nearest whole number?

The fire point is the lowest temperature at which the vapour of oil burns continuously for at least ________ when a small flame is brought near to it.a.1 Secondb.4 Secondsc.5 Secondsd.2 Seconds

For combustion of ethanol C2H5OH(l) + 3O2(g) → 2CO2(g) + 3H2O(l), the amount of heat produced as measured in bomb calormeter, is 1364.47 kJ/mol at 25°C. Assuming all gases are behaving ideally, the enthalpy of combustion ΔCH, for ethanol will be : (R = 8.314 kJ/mol)

Combustion of alkane will produceGroup of answer choicesCarbon dioxide, water, and heatWaterHeatCarbon dioxide

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?

A piece of tungsten of mass 50 g is placed over a flame for long time. The metal is then quickly transferred to a well-insulated aluminum calorimeter of mass 120 g containing 300 g of water at 22 °C. After some time the temperature of the water reaches a maximum value of 31 °C. You may use these values of specific heat capacity : water 4.2 × 103 J kg−1 K−1; tungsten 1.05 × 102 J kg−1 K−1; aluminium 9.45 × 102 J kg−1 K−1. What is the temperature of the flame?