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hi guys,

has anyone done prep work for the flame tests as a solution that is sprayed rather then powder form?? recipes??
im hoping for some great colours

thanks
Jenna

Hi,

I do have flame test spray bottles. I usually make up a "bucket" solution and add 5ml of ethanol.

Works great when the bottles are made up fresh. After a while the spray bottles get clogged up and just refuse to work (because of the chemicals i think).

Also we do this prac as demo only.

Lab-woman

We soak paddle pop sticks in concentrated solutions of the cations overnight. The students then place the paddle pop sticks in the flame just long enough to see the flame colour (any longer and the sticks start to burn). It works well.

we use tooth picks soaked in distilled water. I have the chemicals in labelled vials and the students dip the wet toothpick into the powder then introduce into the flame. Makes less mess than a spray bottle. I have the vials in sets - by using takeaway food containers

use 0.1M solutions and make up copper chloride, lithium chloride, strontium chloride, sodium chloride, potassium chloride and barium chloride.
The flames will be green, pink, dark pink, yellow, lilac and green Have fun experimenting.
https://en.wikipedia.org/wiki/Flame_test

I used to have trouble with the spray nozzles clogging up but now after each use I remove the sprayers, replace with normal lid, and run some hot water through the sprayers to remove the chemicals. Now they last a lot longer as there are no chemicals to crystalise inside them. The sprayers don't get put on the bottles again until next being used. Only mildly time consuming, with a good result.

I use the coke bottle rig that Ocker posted years ago, and it's still the best way to see flame tests.

thanks guys these are all great

Although flame test isn't in our program any more for juniors, there is a component in the yr 12 chem program.
Teacher is set on flame test loops - (for jnrs I have done all sorts of things)
Have been looking at suppliers, but have found nichrome at 11.90 EACH! and they degrade so quickly.
I have also suggested paper clips bent around and held by tongs.
Anyone else have any suggestions?
For inoculation I am looking at getting disposable ones 1000 for $39

rae wrote:use 0.1M solutions and make up copper chloride, lithium chloride, strontium chloride, sodium chloride, potassium chloride and barium chloride.
The flames will be green, pink, dark pink, yellow, lilac and green Have fun experimenting.
https://en.wikipedia.org/wiki/Flame_test

We use spray bottles with these plus calcium chloride. We do not use powders as some are highly toxic (barium!) and we have found in the past they have a tendency to "spit" out when heated. The spray bottles work well if you clean the nozzles every once in a while with distilled water. We also sometimes use the solutions with wire loops.

Our year 9's still look at the flame test when talking about molecular make up and chemical equations.

Narelle, we just use the microbiology wire loops. They are eons old, but a quick wash in methanol and also water and a good burn off and they work over and over again.

I make my own loops. A piece of glass tubing with a hole down the middle (I'm sure it has a "proper" name). I then cut a length of nichrome wire, make a loop by twisting it around, say, a glass stirring rod then insert the wire into the hole down the centre of the glass tube. I've copied this from people who have worked in the jobs before me. The wire seems to hold okay and cheap to replace when they corrode.

For Year 12, they get sample of solid and the previous teacher used to have them clean the loop off in a small quantity of 6M HCl. Not sure of the exact procedure, just know from what he used to order. I've found the spray bottles for juniors just asking for trouble.

capillary tubing

Thanks Merilyn and Sunray and Linotas.
I have some nichrome - will try, and I have the thin glass too. JAYCAR sell nichrome fairly cheaply too.

I'll put it on the list for the days 'i play science'

When it comes to flame tests for juniors, I soak paddle pop sticks in saturated solutions of barium, copper, potassium, strontium and sodium chlorides. I find this is less mess. Works well for open days too.

For safety reasons I don't allow chemicals to be sprayed. We use wire loops that we made with wine corks as the holders. works great and used by our year 10's and seniors only

For safety reasons I don't allow chemicals to be sprayed . We use wire loops that we made with wine corks as the holders. works great and used by our year 10's and seniors only

Narelle,
Who supplies the disposable innoculation loops, please?

For teachers who prefer loops, I make loops using Nichrome Wire. I bought a gauge that fits into the metal inoculating loop handles we already have. It's cheaper to use Nichrome wire than to buy the loops already made, and the loop is more robust. To make the loop I usually wind the wire around a kebab stick. You are able to see a good colour if you use a strong solution.

How strong do you use, Rock? 1M?
I have a teacher who insists on ordering spray bottles, even though I've told her we don't have them. It would be good to provide something that was going to work without the little dears killing themselves!

We actually use close to saturated. That's what one of our previous chem teachers advised. You may want to try a weaker solution if you don't like to use that with kids. We do it in stations to avoid any mixing of chemicals. Solids make the best flame, but we don't do that. I only put out a small amount of the solution, as they only need a loop full to get a flame. I find it's less messy than the spray bottles. I haven't tried the PET bottle connected to the Bunsen idea to contain the spray. That may work better with less mess.