Chemistry

A nice security lady at K.C. airport was kind enough to rattle off the types of explosives her "sniffer" could detect while circling the perimeter of my closed carry-on bag. Seemed they were all nitrate-based compounds, as common explosives tend to be. However, there are many which are different in structure, notably peroxides and various cyclic compounds. Has anyone had a similar screening experience, or perhaps worse, one with medically-prescribed nitroglycerin tablets for heart trouble, which resulted in a boarding "hassle"? Do you feel it was wise that the security person reveal types screened for? Just curious about the effectiveness, and even advisab…

Where might I be able to find a list of molecules that have hydrogen in them. Such as water, amonia, etc. I know there are way too many to name, but where could I find such an answer?

I want to become more familiar with the periodic table of elements and I was wondering if anyone has any tips for me (Easy was to remember certain elements or any good websites ect...)

I need help forming some chemical equations where I only have the reactants. Anyone think they can help?

Hi all, Alright, I am going to start a whole new thread and hope that you people will chipp in with your views about this very hot topic of today's world. "What is Nanotechnology? What future is there for it and how can it help to change our lives?" Lets start this dicussion. I thought of this because I think nanotechnology should be discussed on a wider scale. It is defined as " small science with large benifits". Nanotechnology is the study of materials as small as 10^ -9. Its first was discovery with the finding of Buckministerfullerene or simple bukyball, the 3rd allotrope of carbon. well thats all I know for now. I will come back with more facts…

Hi can't remember how to balance chemical equations,can any one shed some light on the easiest method for this?

Hey, first time post so take it easy on my noobishness Wasn't exactly sure if this should go under chemistry or physics considering that im a biologist so i just chucked it here. We know that molecular oxygen (O2) quenches fluorescent species. We are observing light-dependent rises in fluorescence (we've controlled for more light more F) that have been attributed to a reduction in the solution's [O2]. My question is kinda simple, knowing little about it, does light produce singlet oxygen from O2? Haven't started drinkin yet so my google searches have lacked creativity thus far.

Hi guys whatsup. First off I would like to say, that I really dont have a chemistry or physics background. I am a freshman in college with most likely a business major. That said, I have a question about Luminescence. I was thinking about something and was wondering is there a form of Luminescence (I know there are a lot of forms i.e. Bioluminescence, Chemoluminescence, Electroluminescence, Photoluminescence, etc.) that can be applied to paints? I was wondering this because if so, it may be useful in todays world for a variet of situations. Please let me know if this is possible, as I am very curious. Thanks guys! EDIT: FORGOT THE DETAILS! Details "I apologize. I did …

Hi, Does electronegativity play any significant role in the strength of the acids in a given group? (particularly Group 7A binary acids) I know the general trend across periods... But I'm curious as to wether or not EN has a significant effect down a group. Because HF < HCl < ..... Thanks

Hello everyone, I still am seriously searching for anyone inthe U.S., that might be able to help me in obtaining a few grams or samples of the following compounds ofUranium for my element collection: 1. Uranyl Nitrate 2. Uranium Dioxide, sometimes refered to as "Yellowcake" any and all advice or help is greatly appreciated! Thank you steve

I teach middle school science. Just wondering if anyone had any new, neat ideas/activities for balancing equations. It is a topic my lower kids struggle with each year, so I welcome new ideas. Jennifer Fowler

d. (2 points) Indicate whether the pH at the equivalence point for each of the following titrations is below 7, at 7, or above 7. Titration of: HClO with NaOH ____________________ HClO4 with KOH ____________________ C2H5NH2 with HNO3 ____________________ NaOH with HBr ____________________ e. (1 points) For each of the following processes, predict whether the entropy change is positive (S > 0), negative (S < 0), or approximately equal to zero (S  0). Liquid NH3 evaporates ____________________ NH3(g) + HCl(g)  NH4Cl(s) ____________________ 2NF3(g)  N2(g) + 3F2(g) __________________…

Hi, I was taking a lecture when a lad came into the class and asked my chemistry teacher a question. I happened to listen the question and wondered what the answer could be : " Water is a polar molecule. Sugar dissolves in water when its organic compund. Why?" Strange question I know but whats important is to answer it. I thought that the sugar molecule must have either OH or H groups exposed to water when added to water so that it makes a H-bond with it and dissolves but I think I am not right:embarass: ! Any thoughts any one!

I got an equation here but I can't damn recall how to finish it... some help plz... [ce]MnO2 + HCl -> ?[/ce] I know that this is a way to get elementary chlorine but that's it!

Hi everyone, I'm struggling to know how to realise how many atoms are in a compound if you are provided with the word of the chemical. For example, for Silver Nitrate I know this is a combination of Ag, N & O. I know the electronic config of Ag is 4f1. I would use this as a basis to work out how many O & N atoms I need to fill the 4th shell of Ag. So Ag needs 13 electrons from O & N. Because N & O are bonded together - does this have a different implication for sharing electrons? Or is this totally wrong and in fact it is ionic bonding? I know when s block & p block bond together they do so through ionic bonding, and 2 p block atoms bond togeth…

Hi all, I was just curious to know two things: A. What actually is an 'Isolated' atom? B. How was this name given? I am not sure but I think isolated atom is an atom which is inert and in ground state.

Is the purchase of Iodine (crystals) banned in the US? Also do stores track purchases of substances such as Iodine Tincture? I've bought six 30ml bottles in the past month in a half (three at a time). Would that look suspicious? I use tinc. to make Iodine crystals. It's sad to see chemicals getting harder and harder to get a hold of for the home chemist due to all these drug and explosives makers. Ken

Ok I am trying to make some from house hold ammonia, and 2% tincture of iodine. I put it on a coffee filter, and can get it to turn black, but it seems the amonia, evapoates and the crystal break down as a purple hue forms around the edge of the filter. Or where can I get iodine Crystals...

http://www.hunkinsexperiments.com/pages/nuclearfission.htm This site tells you how to make a homemade nuclear reactor from an apple, a few graphite pencils, and 6 luminous watches. Is this truely possible? Would it work? I came here because i can not find anything else about this anywhere on the internet. I would have dismissed this as a joke, but everything else on the site seems credible. If it is real, is it safe?

I'm trying to think of a type of chemical reaction that involves a rock and some other substance. What kind of rocks are most susceptible to chemical reactions and with what substances do they typically react? Acids? Oxygen? What would be a relatively quick reaction?

Ok this one has been getting me, Does the tempature of a gas change if the presure is changed? I could sware i heard it many times before but my chem teacher says that it does not. some one cair to explain

The question is in the thread. This involves chem equations like for example, FeCl2 is exposed to air. So what does that do, add O2 or what? Thanks in advance

Hi, I was wondering how you calculate bond lengths of HCl? Infra-red spec is an option which uses the mechanism of vibration to determine the functional groups. I want to know would this technique aslo be used to find the bond length of HCl? If so then should not HCl be in Gaseous state? Thank You

Hi erevy1, Could some1 tell me what does this sentence means: "which product dominates"? I think it means which product is in excess? what u think? Thnx

The photos are here... http://flickr.com/photos/21905863@N06/ I use sea salt for cooking and have noticed since I transferred the salt to a glass jar, it has grown pyramids.. Being a mineral, I know that salt forms crystals, but why in this particular shape? Anyone?