Chemistry - June 2007

2007-06-30 22:43:47 · 7 answers · asked by Anonymous

2007-06-30 22:39:00 · 3 answers · asked by College Student 2

I've probably spent too much time staring at the glowing little egg and breathing too many fumes, but for years now I ve melted gold in some old pottery crucibles. Ive had some luck with sticking the tip of a stainless steakknife in the molten gold and slowly sifting-out little pieces of metal that aren't quite in a liquid state. This process I use also is to set up a piece of pottery so it's directly above a cast iron skillet full of distilled water. Once the molten gold is 'clear' (actually looks like yellowish mercury) I get to a point where I take some big pliers and spill the molten blob right into the water. If I could control the spill so that it cools while it's still going down in the water, wouldn't the bottom part be heavier and thus of purer form? If I grind this piece of alloy with a course file into little shavings would that help help before using nit/acid? I've got some merc, too, but I'd like to find a way that's chem-free and just uses gravity. Or melting temps.

2007-06-30 21:21:24 · 1 answers · asked by jemrx2 4

PLEASE HELP ME! I need some help for my assignment over here :)

2007-06-30 20:29:34 · 2 answers · asked by Anonymous

2007-06-30 20:29:32 · 2 answers · asked by air 1

2007-06-30 20:26:42 · 1 answers · asked by Hannah C 1

2007-06-30 19:48:30 · 1 answers · asked by Hannah C 1

explain how a fire estinguisher works

2007-06-30 19:45:38 · 7 answers · asked by chazel27 1

2007-06-30 19:38:35 · 3 answers · asked by Jenasan V 1

is it possible to prepare potassium phosphate by titraing phosphoric acid with potassium hydroxide?

2007-06-30 19:05:07 · 4 answers · asked by Anonymous

(Answer only if you have actual knowledge or has advanced degree in chemistry) Is lacquer thinner safe to use with gasoline as a fuel injector cleaner? We all know those fuel injector cleaners sold on store shelves are a waste of money due to lack of effectiveness or lack of potency when mixed with a tank of gasoline. I have just heard that many racing mechanics keep it a secret that they use 2-3 gallons of lacquer thinner with a full tank of gas to clean the fuel injectors in their own racing cars to keep it in tip top like new condition! - But I thought lacquer thinner is a strong solvent that will damage all types of seals and gaskets. However, i am told gasoline is also a solvent. I also heard that acetone is a better solvent to be used because it is gentle on the hands. Can someone with actial knowledge verify what is true? Is it safe to use lacuqer thinner as a fuel cleaner? Is lacquer thinner a stronger solvent than acetone, and is acetone a stronger solvent than gasoline? Thanx

2007-06-30 18:05:20 · 2 answers · asked by Maikah 2

Hansen solibility parameter is an important parameter,in order to solve a certain material in a solvent. this parameter is constructed by three component, dispersion(D), dipole(P),hydrogen(H) bonding interactions, especially, P and H is very important and need to draw the P vs. H graph.
Then, I have a quesion.
Would someone tell me how to determine Hansen parameter and R which is distance between a material and solvent by drawing P vs. H graph,
when a material(powder,solid) which Hansen parameter is not
known can be solved by some solvent(organic solvent) which Hansen parameter is known ?

2007-06-30 17:27:05 · 1 answers · asked by Motohiro T 1

it has a connectioon with chenistry. just definition,cause, effects and what does it have to do with us.

2007-06-30 16:40:16 · 4 answers · asked by "marjorie kyle" 1

can any1 explain y this happen in detail? thanks...

2007-06-30 16:03:55 · 3 answers · asked by sonicdipsy 1

2007-06-30 15:43:37 · 3 answers · asked by Anonymous

what is the pH of 500mL of soln. containing 0.0124 gram of Ca(OH)2.

If anyone can help me set this up that would be great!

2007-06-30 15:34:20 · 3 answers · asked by Anonymous

Calculate the pH of a soln of acetic acid that is 3% ionized, Ka = 1.8 x 10^-5.

Ok, thanks to the help from a very kind person, I realized what I needed to. But now, Im getting the wrong answer over and over again. I get 3.13. But thats not one of the options I have for the answers. If anyone could help me out I would appricate it.

2007-06-30 15:03:27 · 3 answers · asked by Anonymous

I just need a little hint for this, I would like to be able to figure it out myself.

Calculate the pH of a soln of acetic acid that is 3% ionized, Ka = 1.8 x 10^-5.

Since I don't have M of the solution, I can't solve by
% ionization = [H+}Equil / [HA]i

please help me understand what approach to take. Thank you in advance.

2007-06-30 14:41:31 · 2 answers · asked by Anonymous

2007-06-30 14:27:29 · 4 answers · asked by Akilesh - Internet Undertaker 7

White crystalline salt "P" --->warm aqueous sodium hydroxide ---> gas "Q" ---> moist red litmus ---> blue.
White crystalline salt "P" ---> aqueous salt ---> dilute nitric acid with aqueous silver nitrate ---> to produce white precipitate "R".

Name the substance "P", "Q" & "R".
Solve this question correct with detailed workings and earn points!!! :)

2007-06-30 14:08:16 · 1 answers · asked by Anonymous

2007-06-30 13:47:09 · 2 answers · asked by Anonymous

2007-06-30 11:38:25 · 11 answers · asked by i_love_jt0 1

2007-06-30 08:44:13 · 5 answers · asked by Anonymous

My daughter brought me a little 4th of July toy. A pinch of pebbles wrapped in a bit of tissue paper. One throws these at the ground and there is a small popping explosion. I had guessed there was a bit of gunpowder mixed in with the pebbles, but when she and I opened one, there was no evidence of any black powder. How do these things work??

2007-06-30 06:40:37 · 4 answers · asked by Springerrr 2

2007-06-30 06:29:29 · 7 answers · asked by Anonymous

please your answers must be in details and chemistry related. thanks a lot.

2007-06-30 06:09:32 · 5 answers · asked by moi 2

I am 18 weeks pregnant I was opening up the dishwasher and I thought it had sat for a while and the steam was gone...Nope it was there and in my face on a breath in. I looked it up and there is Chloroform that forms in the dishwasher because of the mix of chemicals with the clorinated water.

Now I am scared.... I looked it up and saw that there was a warning about this and I never knew it and there is even a warning about using Trilosan based hand wash and Chloronated water... That it too causes The gas.

I hope I didn't just do damage to the baby. I stopped breathing in when the steam got in my throat.

I am not getting movements regular yet so I have no reassurance at this time either.
I hate this Toxic world.

2007-06-30 05:29:42 · 3 answers · asked by Angelus 4

2007-06-30 05:21:31 · 4 answers · asked by ocirmag 1

2007-06-30 05:17:29 · 1 answers · asked by samo 1

This blue crystaline solid ---> dissolve in water and add dilute nitric acid and barium nitrate solution ---> a white precipitate "M".
This blue crystaline solid ---> dissolve in water & warm with NaOH solution ---> a gas "N", that turns red litmus blue.
This blue crystaline solid ---> dissolve in water & warm with NaOH solution ---> a blue precipitate, "O".
This blue precipitate, "O" is mixed with excess dilute sulphuric acid to give a blue aqueous solution that evaporates slowly to give a blue crystals, "P".

Q: What is the identity of substance "M", "N", "O" & "P"?

Solve this question correct with detailed workings and earn points!!! :)

2007-06-30 05:09:03 · 3 answers · asked by Anonymous