Salt formers

Last time I asked “What do you predict would happen to a bunch of brightly coloured flowers placed into a gas jar of chlorine?” Well, of course, the flowers would be bleached white and this is indeed what happened.

Bleach them white

Bleach them white

Chlorine is an element in Group 7 of the Periodic Table, a group called The Halogens. The halogens are: F = fluorine, Cl = chlorine, Br = bromine, I = iodine and At = astatine.

Salt formers

Salt formers

The elements exist as diatomic molecules and we had some fun doodling this the other day.

Hand in hand

Hand in hand

Britannica.com says “the name halogen, from the Greek roots hal- (“salt”) and -gen (“to produce”).” Thus, the halogens produce salts and in my blog of November 1st 2012 I showed some pictures of sodium chloride, sodium bromide and sodium iodide. I don’t have any sodium fluoride, but this too should be a white, crystalline solid.

Sodium fluoride is toxic if swallowed and liberates very toxic gas on contact with acids (CLEAPSS Hazcard 95A, 2007). Presumably this could happen in the stomach if large amounts were ingested. Fortunately, only very small amounts of sodium fluoride are added to fluoride toothpaste (for example 0.32% w/w). Probably best not to swallow your toothpaste anyhow, just in case!

The formula for sodium fluoride is NaF, what would be the formula of calcium fluoride?

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s