Tuesday, February 16, 2010

Combustion of a candle (Combustión de una vela)

Materials:
A soup bowl
A candle
A narrow glass

We fill the plate with water
We light the candle and put into the plate so that the glass doesn´t touch the flame
We place a glass on the candle. We wait for a moment and we see that the flame goes out, and them comes into the water in the glass.

When we light the candle, it produces a combustion reaction: the wax of the candle reacts with the oxygen of the air and produces carbon dioxide and water steam. We can see that inside of the glass appear a few drops of water. It is the water steam produced in the combustion of a candle that is condensed in the walls of the containers.

In the reaction the gas is consumed, the oxygen that forms a part of the air, but other two are formed, the carbon dioxide and the water steam. The volume of the gas produced, is smaller than the volume of the oxygen that is consumed.
The results is that in the interior of the glass the pressure is reduced and because of that the water goes up until the interior pressure is reduced and because of that the water goes up until the interior pressure is equal to the interior one


by Amelia and Laura

8 comments:

  1. Maria L.:
    Congratulations, good job! :D

    ReplyDelete
  2. WELL DONE! THIS EXPERIMENT HAVE BEEN WORK WITH A LOT OF TIME OF ANTICIPATION.THANKS


    B.D.S

    ReplyDelete
  3. Enrique O.
    well done!!! it´s a graet work, congratulations!!!

    ReplyDelete
  4. I´m sorry, the explanation isn´t correct. The difference of volumes of those two gasses isn´t big enough. But there is another more important effect. The candle warms up the air inside the glass, warm air expands (you can see bubbles). That´s the reason why the air pressure outside the glass pushes water inside after the candle goes out.

    Vladimíra

    ReplyDelete
  5. Well done Amelia and Laura. You´ve done it quite well. I don´t know if the experiment is correct but your English is not bad at all and it´s rather difficult when you are being recorded with the camera. You will have a good mark in our subject. Adelaida

    ReplyDelete
  6. Álvaro et GonzaloMarch 15, 2010 at 5:26 AM

    C´est un bon travail. C'est très bien fait. Nous voyons que vous avez travaillé beaucoup.

    ReplyDelete
  7. Bon travail de groupe!
    C'est experience est très bien!
    C'est très interessant.
    L'explication est très bonne!
    Félicitations!

    ReplyDelete
  8. Salut! Nous sommes des élèves de français.
    C´est très interessant et amusé
    ¡Félicitations!

    Vero y Pepe

    ReplyDelete