Wednesday, 5 June 2013

Covalent Bonding (Clingy Girlfriend)

Ever had that one girl? Wants to SHARE EVERYTHING. Me neither. #foreveralone. Anyhow covalent bonding is that girl. This girl:

The simple way to put it... Both need a full outer shell. They have to share an electron. CO-valent. Co-operate. See a link?

as you can see they both want a full outer shell so share. Their mothers would be so proud.

Barium Meals and Flame Tests

Barium Meals

No way around this one, have to learn it.


  1. Mix solutions of barium nitrate and potassium sulfate
  2. Filter out the precipitate of barium sulfate
  3. Wash it with distilled water.
  4. Dry it on filter paper.
Surely you understand that? Simple stuff really. The key thing to remember is that Barium Sulfate is a mixture of Barium nitrate and potassium sulfate. It often asks for a PURE DRY SAMPLE of Barium Sulfate so... You need to use pure distilled water water to create a pure sample. And you need to dry it . Simple as that! If you hadn't guessed then all of the underlined words relate to the 4 steps above. What can go wrong?

What can you use this for? Well the key things are for x-rays. Barium Sulfate is opaque so in x rays shows up. This allows them to detect blockages in the blood stream. It can be safely drunk because it is insoluble.

Flame Tests

You have to remember the pretty colours.

  • Sodium: S... Sandy... Yellow.
  • Potassium: P... Purple... Lilac.
  • Calcium: My leavers hoodie is red! Not much use to you... But hey ho.
  • Copper: Ever had a blue car? Should have done, make it easier to remember.