Monday, May 9, 2011

DIY Fossil and Rock Store carbon @ PSN 5thMay2011

The preparation done by the lab staff at PSN is commendable. Everything was meticulously laid out, neatly in plastic containers, one for each table. We were at PSN for 2 activities.
Activity 1 - to investigate which rock contains carbon
Activity 2 - To make our own fossil from plaster of paris.
This time around the kids got to handle test tubes.
A booklet was given out with detailed step-by-step instuctions.
A lab assistant showing us some samples of fossils that we were going to make.
Fai and Arian rolling out plasticine.
Pressing the cockle shell into the plasticine to make an imprint.
Mixing the plaster of paris with water and blue dye.
Spooning in the plaster mixture into the cockle imprint.
While waiting for the plaster to dry, the kids did a quiz on dinosaurs.
Ean's cockle fossil.
Next, the kids got to do some investigative work - find out which sample contains carbon.
5 samples were given. Cockle shell, charcoal, egg shell, granite stone and coral.
Place a sample into a test tube. Pour in 10ml of vinegar.
Watch for bubbles. The bubbles would mean carbon dioxide is evolved. The acidic vinegar reacts with the carbon in the sample giving out carbon dioxide gas.
Fai and Arian observing the evolution of carbon dioxide gas.
Eggshells in vinegar. See the bubbles being produced?
Bromothymol blue was used to indicate the acidic carbon dioxide gas. Bromothymol blue changes colour from blue to green to yellow when carbon dioxide is bubbled into it.
JY blowing into bromothymol blue.

Science makes my boys hungry. While the other kids were busy with their test tubes, I made an exit and fed their growling tummies.

No comments: