Coffee.

Mmm

Starfish…

Starfish are very interesting. They belong to the Asteroidea Class.

This one is a Cushion Starfish Patiriella regularis.
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Identification is by the pair of white spots. Starfish have many small tube feet; mini suction cups that the starfish uses to move. You can see them in the picture below:

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Some Starfish like this one live in intertidal rockpools.

Bye – C

Playing with fire.

We got to use the amazing facilities and equipment at Canterbury University, in a practical chemistry lab. 

We dipped nichrome wire loops in solutions of metal, then we put the wires in the flame of a Bunsen burner. The flames were diverse in colour:

  • Greenish for barium.
  • Greenish for copper.
  • Almost white for lead.
  • An orange red for calcium.
  • Pink for potassium.
  • Yellow for sodium. 

 We also tested some unknown solutions to figure out what was in them.


How does it work?

The flame excites the electrons. the colour is caused by electrons falling to lower energy levels. Different atoms have different energy levels and so emit different wavelengths of light.
I will probably try the sodium and copper flame tests again at home.

All in all a good experience. The lab had a lot of nice equipment…

Until next post

CM

P.S. “Playing with fire” is a really good book by Derek Landy