[tori]

Give the results of the flame test viewed with and without the cobalt glass on the MIX SAMPLE of KAl(SO4)2`12H2O and Na2CO3. Comment on what indicates about KAl(SO4)2`12H2O.

How to answer this question?so confused...

[cth]

For a flame test, you dissolve your compound in HCl and put a drop of that solution into a bunsen burner flame. Then you look at the colour change of the flame, if any. Some compound have specific colours, see http://en.wikipedia.org/wiki/Flame_test.

In your particular case, what would be the colour?

[tori]

For a flame test, you dissolve your compound in HCl and put a drop of that solution into a bunsen burner flame. Then you look at the colour change of the flame, if any. Some compound have specific colours, see http://en.wikipedia.org/wiki/Flame_test.

In your particular case, what would be the colour?

Thanks for your help. But I just don't know the answer cause there are MIXED samples....

[marquis]

Yes, they are mixed samples.

Potassium, if it is present, gives a purple colored flame.  Sodium gives yellow flame.  I think aluminum is in the uv.

The kicker seems to be the cobalt glass.  I think it will filter out one of the wavelengths from the two elements.  Not up on cobalt glass, though.  Don't know which wavelengths it absorbs.