Chemistry final. In need of assistance.

[Burbuat]

Let me begin by introducing myself,

 

Well, I will refer to myself as Burbuat. I have, for the past 4 days, tried to identify an unknown substance provided for me by my teacher. We have 8 days to identify this unknown substance, but I am afraid I will not be able to correctly identify this unknown substance without proper assistance.

We have run some basic tests to try to hint at what the substance may be, but I will need your help in narrowing it down.

 

We have done a flame test, and the flame burned at an orange/yellow flame, although my group swears they see a tiny hint of purple now and then, but I believe that is just paranoia sinking in form our approaching deadline.

 

We have also done a percipitate test, and we had results that hinted at the fact that our substance has Chlorine in it because the test tube was filled with clumps of a white flaky material, and the water became hazy. We conducted this lab with Silver Nitrate, we placed our unknown substance in a test tube, and we put a few drops of silver Nitrate into it. And the above percipitate formed.

 

In additon to that, we did a conductivity test. Which was a test in which we hooked up copper wiring to a battery, and placed these positively and negatively charged wires into our unknown substance, which we poured onto a watchglass. After a while, green colored clumps began to form in the pool of our unknown substance. And the water took on a slightly gray tint to it. We also clipped a light bulb onto the copper wiring to see if the compound we had was covalent or ionic, the lightbulb didn't light, so we assumed that the compound is either a very weak Ionic bond or a Covalent bond. But remember, our substance has been significantly diluted, it is about 90 percent water and 10 percent substance, and I believe that is why the lightbulb did not light.

 

Finally, we conducted a PH test and the PH of our substance was 7.

 

Now, our unknown substance is one from this list...

 

Sodium Borate.

Potassium chloride.

Calcium chloride.

Or Sodium chloride

 

I humbly ask you for assistance... and contribution would be greatly appreciated.

 

-Burbuat

[Newbies_Kid]

Liquid hydrocarbon?

[Mr Skeptic]

All the info you need is your flame test and chlorine test.

[PharmaSci]

Hey, just to reiterate what has been said before, the results of the flame test and the precipitate test are the ones to consider here (what element gives the yellow flame colour (possibly "golden yellow") and which likely anion gives a positive result in the ppt test with silver nitrate?!) As for your collegues seeing flecks of purple in the flame...they may well have! I assume this test was performed using a bunsen burner. Bunsens can often give erronious flame colours since old powders from other similar tests can fall into the burner. It could be that the flecks of purple observed were the result of these old powders burning too! Or, as you say, it may be a little over-excitment (perhaps mistaking the slight blue tinge to the methane flame for purple). In sort, go with the colour that was most prominant.

 

Hope this helps!