Thursday, March 4, 2010

HOMEMADE FIRE EXTINGUER (Un extintor casero)

Our experiment is called: Homemade fire extinguisher.

The materials we need are:
-Bicarbonate of sodium
-A glass
-A candle

Place in a glass a bit of vinegar, three or four centimetres
Add a little bicarbonate of sodium,many bubbles appear.
If we light a match and put it in the glass, it will be put out instantaneously.
If we incline the glass on a candle,without spilling the vinegar, we will see that the candle is put out.

The chemical reaction between the bicarbonate of sodium and the acid of the vinegar produces a gas called dioxide of carbon.
This gas weights more than the air so that it remains in the glass displacing the contained air in the glass.When putting the match in the glass it is put out, due to the lack of oxygen (necessary for the combustion)
When we incline the glass on a candle this is put out because the dioxide of carbon falling on the candle displaces the oxigen that maintains the combustion.

En español:
Nuestro experimento se llama un Extintor casero.
Los materiales que nosotros necesitamos son:
-bicarbonato de sodio

-un vaso
-una vela

Coloca en un vaso un poco de vinagre (tres o cuatro centímetros )
Añadimos un poco de bicarbonato de sodio. Muchas burbujas aparecen
Si metemos una cerilla encendida en el vaso se apagara al instante.
Cuando nosotros inclinamos el vaso sin derramar vinagre,nosotros podremos ver que la vela se apaga.

La reacción química entre el bicarbonato de sodio y el ácido del vinagre produce un gas llamado dióxido de carbono.
Este gas es mas pesado que el aire por lo que permanece en el vaso desplazando el aire contenido en el vaso. Al meter la cerilla en el vaso se apaga por la falta de oxígeno(necesario para la combustión)
Cuando nosotros inclinamos el vaso sobre la vela, esta se apaga porque el dióxido de carbono cae sobre la vela desplazando el oxígeno que mantiene la combustión.

Marta y Pilar


  1. Maria L.:
    Congratulations! The experiments is explained very well! :)

  2. You have worked a lot for this experiment, including your TV session. As a teacher I´m really happy to see you are quite motivated with the project as well as your partners.Of course it´s going to improve your English level and your MARK!
    We´ll do more activities soon.

  3. We have done a great experiment, everything the followed(consecutive) one and without problems. Thank you for giving this good image in the televison on us.


  4. salut! L'experience est génial, vous l'avez très bien fait.
    Reyes et Miguel.