Applied Chemistry

You know how you can twist a closed water bottle until enough pressure builds up shooting the cap far far away? Why is it that vapor comes out of the bottle? At first I assumed that increase in pressure would lower boiling point of the water, but in fact, it raises it and therefore this would not be the cause of the vapor. What is it?

i am doing an experiment on the preperation of a yellow solid i am stuck on the risk assessment i have the hazards (can cause burns, irritating to eyes, corrosive, toxic e.t.c) can you help, risk assessment for ammonia solution sodium thiosulfate potassium dichromate acetone nitric acid solution (to be heated) copper (ii) sulphate iodine ammonium persulfate i hope you can help me ive been all over the internet and read countless books but all they seem to give me is the hazar…

-log(concentration of H+ ions) the above is the formula for calculating the ph of an acid... however, when the concentraion is 1M, the pH is 10.. but how could that be?? it should be less than 7, because it is an acid.. secondly, how do you calculate the "alkalidity" of pH?? thx

Okay I'm new to the forum (hello all) and I really need help on accelerated chemistry (11th grade). The question is: What is the final temperature of water if the initial temperature is 280k and it's heat content is 350.00 kJ and 36,000 Nm of work is performed on it by compression? I have no clue how to do it and any help would be greatly apperciated! EDIT: Sorry, I didn't see the homework help forum, I'll post it there...

E system = E surroundings. I can't make sense of this, can someone explain this to me? Is this saying that all forms of energy are equivalent?

I have this debate thats coming in class about being a pro Nuclear person. I'm the leader of my group and I'm asking for help in deffending my group. I've done my research and since Im in the Philippines and It has top be related to us here, Im having doubts of help. But it would really be nice to hear from diff. Points of view. Thanks.

I once built an ice bomb. I took a 10 inch steel pipe, filled it with water, and capped and sealed both ends. I put it in the freezer, and a few hours later...BOOM. Pipe destroyed, freezer damaged. So I asked myself a question: What is the maximum force that freezing water can exert as it expands? What if I tried it with steel chamber where the walls have various thickness. What if the walls were one inch thick? One foot thick? Is there a limit??? Steve-O

my mom makes this really awesome pork chili. when she makes it she always makes surplus so we can freeze it and have it for leftovers later. the thing is, when i reheat the frozen stuff it seems to have almost completely lost its spiciness. its no longer hot, its like thick soup instead of chili. is there some explaination for this?

Why do buffer solutions resist changes in pH? Please include appropriate chemical equations and calculations. Thank you, and pls reply ASAP, because it is very URGENT!

Does anyone know of a good physical chemistry text book that I could purchase? I want something to supplement a physical chemistry course I will be taking in the fall.

Just watched the least creditable show on discovery channel "Myth Busters" And they talked about mystery bullets. A bullet whos properties prevent it from leaving any ballisticks evidence. Like something made of ice. They did tests with frozen H20 bullets which weren't able to reach their target bue to vaporization. So I was wondering if any other substances could be frozen fired out of a gun and do damage to a target then "Dissapear". Also I'm wondering if you could have a bullet made of a highly reactive metal like Rubidium which would react with the victms blood. Could this work?

hi, guys. years ago, there was this friend of mine who said that we can't cut glass with an ordinary scissors in air, but we can in water. He tried cutting it in air; it didn't work. So he prepared a little tank (that kind of tank where you keep your turtles) and filled it 3/4 of tap water. Then he got a piece of glass (he claimed it was from a broken window) and immersed it in water. His other hand held on the scissors, submerged it in water, and started cutting it. But I wasn't sure if the cut was smooth or rough. Is it really possible that glass acn be cut in water?

Are there any non toxic coloured gases at all? I've been searcing the internet to find one but haven't come across any yet. I've been putting together a short play where one of the actors has to breathe in a small amount of "poison" gas and i was hoping I could have the gas that they breathe in be green but any colour would do really. Any suggestions?

I've only found things that seem to clump everything together.. no one has seemed to want to create something on proboards or anything...

ok, so im selling a book on ebay called "A LABORATORY CHEMISTRY". It was published in 1904. The book is very cool for any chemist but ive read it through. I understand that there is a thing against advertising, but i think people here would enjoy using this book. It is a good resource. Mods, if you feel that this is not appropriete (linking you to my ebay auction) please just delete the thread. Im postig this because some one here might want this book. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=2228&item=6966444224&rd=1&ssPageName=WDVW

According to my teacher Dr. Istone who has a PHD in Chemistry, there is a mixture of chemicals that when ignited burn at a low enough temperature for the skin to withstand it. He used to be a Chemical Magician (one of his 100's of jobs) and one of the tricks he did was ignite the mixture on his arms and walk around while on fire. One of the characteristics of the flame is that the color is a blue tint. Please help me because my teacher was going to show us this demonstration but we ran out of time at the end of the year. Anyone have any ideas? Thanks, ThermiteMan

If something has a flash point of say, 30C, that is the temp that it will ignite at, right? but once ignited, will it get hotter? And does anyone know of anything that burns at a low temp that will not burn flesh. also, if anyone knows, where i can purchase some. tee hee thanks in advance.

Hi, I am just starting to learn chemistry and was wondering what the best way to go about it would be. Is it useful to memorize the whole periodic table with some of the key characteristics of each element? Also, i have alway wondered what chemical equations were. Would someone be able to give a brief explanation about what they are and what they are used for. Also, how do you become good at them. Another thing i've always wondered is, there seems to be millions of different compounds, is it just a matter of having good reference material or is it necessary to learn most of the most common ones. Sorry if my questions are too basic Thanks

I cant seem to find a semiquantitative test for nitrates in solution when in prescence of nitrites. The only one I can find involves Hg. Any simple solutions (no pun intended)? This is for my fish tank. No need paying the fish shop for chemicals if I can do it myself.

Is there any chemistry channels on IRC?

This thread is a thread for people to post elements that are in common household items. Here Are A Few To Start Out... Zippo-Pt, Rh Pencil-C Lightbulbs-W Pots And Pans-Fe Fishing Weights-Pb Smoke Detectors-Am, Np Jewelry-Ag

hey , i can't see why this is called 2-Methylethyl or why it is then called ISOPROPYl if someone has the time, could the please explain this too me ? Thanks Sarah

I've decided to take up element collecting. What elements can I find around the house?

What can I do with the following chemicals/substances? Cobalt chloride hexahydrate pottasium iodide copper sulfate copper oxide Sodium carbonate Ammonium chloride Potatssium aluminium sulfate methl orange Iron sulfate Magnesium sulfate epsom salts litmus blue sodium thiosulfate hypo Calcium carbonate Sodium hydrogen sulfate Sodium sulfate calcium hydroxide slaked lime Tartaric acid sodium chloride water (duh) magnesium copper iron zinc

I was watching a show bout firefighters. To burn off flammable underbrush in forests so they dont ignite later, they filled ping pong balls with a chemical and dropped them from helicopters into the area that they wanted to burn the underbrush in. When filled with the chemical, the balls would ignite with a few seconds delay, i think it was 7 seconds. Does anyone know what the chemical could be?