Masse volumique

Masse volumique

La masse volumique est une propriété caractéristique de la matière.
La masse volumique d'une substance est définie comme la masse par unité de volume.

Résultats d'apprentissage

L'élève sera capable de :

• Définir les termes suivants : masse volumique, volume, masse
• Réaliser que la masse volumique est une propriété caractéristique de la matière
• Spécifier les unités SI de la masse volumique
• Résoudre des problèmes relatifs la masse volumique
• Appliquer les concepts de longueur, masse, aire, volume, etc., à des tâches spécifique

Demonstrations

• Tour de masse volumique virtuel (voir ICI pour plus) (More on virtual density towers)

• Lava lamp - voir autres photos et videos ici (See here for more about the lava lamps)

• Labo de masse volumique virtuel***
•  (www.learnablerta.ca and search density for the online virtual lab)

Tasty treat - Make your own Shirley Temples to show stacking fluids!

Kitchen Lava Lamp

I found this idea online and it is PERFECT to demonstrate density!  The oil floats on the water because it is less dense.  If you add an alkaseltzer tablet it makes bubbles that are less dense than oil and rise to the top carrying drops of water with it.  Once they reach the top and the gas escapes the water sinks back down.  Very cool!  Click HERE to see the video

A water bottle with air, oil, and water

Add some food colouring to the water!

Alkaseltzer bubbles - LAVA LAMP!!

Very pretty!!

Kitchen Lava Lamp Video

How cool is this??  Click HERE to learn more and get instructions on how to easily do this at home!

Density Tower

I did another fun demonstration for my grade 8s this week.  First we looked at what solid objects float on water and which sink (see photo below for results).  Then we talked about density and how less dense fluids will float on those that are more dense.  I constructed a density tower with NINE different fluids.  Then we took the same solid objects and observed which ones floated, which ones sank and at what level they rested.  It was very good at showing them everything we have been learning and something you can try at home.  See this website for instructions.

To illustrate the practical applications, other then petrochemical ones, I made them each a mini Shirley Temple showing them how orange juice floats on grenadine!  YUM!!

Supplies

What floats on water?

Tower before and after!