jowrose

So then treating my sand-Fe3O4 mixture with HCl will work well to purify it (at least removing some impurities). Thats good.

But what about Fe3O4?

While we're at it, why not top 5 comedy movies? This might already be a thread somewhere though, I'm not sure. 1. Airplane! 2. The Naked Gun 33 1/3 3. Hot Shots Part Deux 4. Dr. Strangelove 5. Airplane! 2

1. The Daily Show 2. The Colbert Report 3. Family Guy 4. Seinfeld 5. Stella (I can't believe they cancelled it! Ridiculous! They only played like 6 episodes!)

After a few days, you would notice that the rust was gone...

I know, I was doing some research and found it takes massive amounts of pressure to get a solid (or -75 degrees C)... Not something I could create in my basement... I believe there were small amounts of HCl gas, but other than that I would think water vapor would be the only contaminant. I will take a look though and make sure.

Over the summer I used some very powerful neodymium magnets to obtain some magnetite, with the hopes of being able to purify it to thermite-grade (I failed). I know that HCl reacts with Fe2O3, so I decided to use some of my magnetite to observe a Fe3O4 reaction. When I put the reactants in the test tube, I noticed that only a few bits of sand mixed in with the magnetite seemed to be reacting. A few days later, I ran a magnet over the solid left at the bottom of the test tube, and it's still magnetite. Why didn't it react? I suppose it's possible that it reacted, and the Fe3O4 was in excess, but the test tube doesn't seem to have lost any magnetite at all.

I recently tried using ammonia as a reactant for a reaction (no reaction occurred), and placed the test tube in my homemade storage box/ fume hood. The next day, some what crystals had formed at the top of the test tube. I am almost sure that no reaction occurred (at least in the test tube), as I have gotten these same crystals with other ammonia experiments. They are perfectly white, and have a texture almost like that of a feather. Does anyone know what these crystals are?

When I think of a computer, I imagine myself communicating with others and transferring knowledge.

I was just wondering if anyone knew how stem cells are differentiated from their embryonic form into the specialized cells needed to cure disease. Is this done genetically, or do the cells automatically transform into the type of cells that they are surrounded by (i.e. one could place stem cells on a destroyed nerve ending and the cells would naturally become new nerve cells)? Or does it have something to do with the protein markers on the outside of the cell? Any reputable sources that deal with this procedure would be nice, and all help is greatly appreciated. Thanks, John

Why does the Cu(OH)2 dissolve when more CuCl2 is added? I don't get that.

Ok, I tried the reaction and got similar results. I add drops of CuCl2 (aq) to NaOH (aq) and the blue precipitate forms, and after a while the CuCl2 doesn't react anymore. However, I swished the test tube around and the precipitate dissolved, leaving a green solution (lighter than the CuCl2 soln). So I add some more NaOH, and I get a black precipitate. What is going on?

I put in some copper wire a few mm thick. It seems that it has gotten thinner, and the solution has turned a very dark brown. Only half of the wire was submerged, and the other half has grown some brown compounds on the surface. Thanks woelen and YT for the help. I'll wait some more, and if it isn't working I'll add some NaCl and some HCl to add chlorine and purify the FeCl3. Every day, I learn how incredibly oversimplified my high school chemistry class is...

Ok, I have some FeCl3 that I have created, and somewhere I heard that this is used to dissolve copper. I took some of my (hopefully) FeCl3, put it in a test tube, and placed some copper inside, and there was no reaction. Does this reaction take a long time, or is what I think is FeCl3 something else (perhaps with lots o' impurities)? While I'm at it, I might as well ask why this reaction works, seeing as copper is a very unreactive metal.

Agar is relatively simple to make, but it's not as good as agar you could buy on Ebay or other online stores. It involves gelatin, beef bouillion, and sugar. I've made several petri dishes full of it, but have only succeeded in growing mold... The hardest thing to do is keep the dishes from being contaminated, especially if you're planning on keeping the samples in your basement.

going back to stsanthony's question of destroyed lab glass... I was heating, oh, maybe 300 grams of potassium nitrate and sugar (to make smoke bombs, of course) and it ignited prematurely... needless to say the 1000 mL beaker was destroyed, and it took about an hour to get rid of all the smoke that was hovering around my basement.

Ah, thanks. Tis getting clearer. So you can use an activity series of metals to determine which of those will be oxidized, but what about nonmetals? Is there a given rule to determine which elements will be reduced or oxidized, or is there just some chart somewhere?

Ah ok. thanks yt.

Ok, I understand the general reaction of electrolysis; The anode takes water and creates oxygen molecules, hydrogen ions, and electrons. The cathode takes water and electrons and creates hydrogen molecules and hydroxide ions. Furthermore, when a salt is dissolved in the water, electrolysis separates the two components of the salt, the anion to the anode and the cation to the cathode. What I am confused about is the role the cathode and anode have in this process. Say I'm using copper electrodes and NaCl as the electrolyte. Sodium is drawn to the cathode, where it combines with hydroxide ions? The chlorine is drawn to the anode, and it combines with hydrogen ions? And what about the copper? Does it combine with hydroxide ions at the cathode, and oxygen at the anode? I am confuzzled.

When you place a steel (iron) nail in a CuCl2 solution, the iron first displaces the copper and forms FeCl2, because iron is more reactive than copper (take a look at an activity series of metals). If you leave the FeCl2 out (it is a clear solution, with a slightly green tint) in contact with air, it slowly oxidizes to form FeCl3 (a yellow-orange solution). Of course, the colors could be mixed up, as no nail is pure iron. You will get impurities ranging from carbon (if it's a steel nail) to magnesium to nickel. If I'm wrong, I hope somebody will correct me...

Ok, I've been doing some electrolysis but I cannot figure out how to make a salt bridge to keep the reactions separate. I've tried using yarn wet with the solution, but that didn't work. So I tried using thin strips of paper towel, and that failed as well. So then I took a piece of tubing and siphoned it so that it was full of solvent, and again I was left with no reaction. What am I doing wrong?

Ok, thanks for the advice. I don't have much extra money lying around (If I did, an autoclave would be one of the last things I'd buy...), so I'll just boil the growth medium and kill off all the unwanted organisms.

So it loses force, but does that affect stability?

Is there a special device needed to autoclave? Or could I just make my own with a hot plate, flask, water, and some tubing?

What do you mean by VOD?