The Chemical Change in a Candle

The following article includes pertinent information that may cause you to reconsider what you thought you understood. The most important thing is to study with an open mind and be willing to revise your understanding if necessary. If you don't have accurate details regarding science, then you might make a bad choice on the subject. Don't let that happen: keep reading.

We all must have been familiar with candles. Yes, a thing that can give light in darkness. But have we ever wondered how a candle can light a fire? In this article I will try to describe it in a concise and hopefully easy to understand.

Candles made of flammable substance called paraffin. In a paraffin wax contains  the element Carbon (C).  When paraffin exposed to fire, the molecules in the paraffin will turn into another molecules form contains of  carbon. This molecules is floating around the fire and the candles, and the candle combines it with Oxygen  (O2) from the air into Carbon Dioxide (CO2) and produce an energy. The energy is light and heat. When we look at the size of a burned candle, the candle will slowly shrinking. It is not because the fire consumes the candle, but because the paraffin wax has been changed into energy molecules that produce fire and heat. The life of fire relies heavily on the paraffin wax, so when the paraffin has gone there will be no other energy that can provide fire and heat. This is what we call a chemical change

The changing process of  paraffin  molecules into a fire can not be seen with our eye. But try to look at when we blow out a burning candle, when the candle is out, there will be milky white smoke coming out and also the smell of  paraffin. This is because  paraffin has been changed back from the energy molecules into smoke before it disappears along with the air. This white smoke is the rest of paraffin that has not turned yet into a  flame because there is no source to generate fire and heat anymore.

Paraffin can not be lit by themselves. Like the fire that needs a paraffin wax, but paraffin also needs a fire source to be able to create a flame. Now we will prove through a small experiment that the smoke comes out from a candle when it's blown out is the paraffin molecules that turns into smoke. My friends thought that I used some magic trick when I did this : ). There is no magic in this thing, it is completely science.

Things to prepare:
1..Set up a candle and a match.
2.Light the candle with a match until the flame of the candle burns perfectly.











3.Then blow the candle until the flame dies and the white smoke comes out from the candles.













4.Light your match and direct the fire into the smoke but  not too far from the wick.
 


































5.Don't be too long because the fumes of paraffin will soon be gone with the air and  the smoke is left only a residue of burning wick, so it won't work. Try it and Abracadabra ... see for your self that the candles can be lit without you touching the wick.
   
So now you know a little bit about science. Even if you don't know everything, you've done something worthwhile: you've expanded your knowledge.....  

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What is an Echo?

Have you ever gone to mountain or a valley? If you get there try to shout "Hello" then within seconds there will be a voice that respond. Whatever you shout that voice will say the same thing. That's not a ghost voice but our voice is returning. This is what we call an echo.
The word Echo comes from the Greek. In ancient times in Greece echo is described as the voice of a girl named Echo who fell in love with a man, but unfortunately he did not love her. Eventually the girl disappeared, she faded away and nothing was left but her voice.
How the sound returns
Echo comes from our own voice back due to the reflection. When we shout, our vocals cords vibrate and produce sound waves and the waves will travel through the air. If the sound waves hit a solid materials such as walls or mountains, the waves will bounce and head back. In short time the returning sound waves reach your ears so you can hear it.

Why we cannot hear the echo in our house
There are several requirements to make an echo. First there must be a high sound like when we shout, then number two there must be a solid molecules for the wave to bounce back. A sound has a very high speed. It could reach about 1100 feet in 1 second. We will not be able to hear echo if the distance where the sound waves bounce is too close because a sound needs time to travel. If you say "Hello" to a wall close to you, the sound does bounce from the wall but it goes to you in so little time that you cannot make it out. For your experiment you could go to a mountain, bring your stopwatch and start to count how long it will take for your sound to return.

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