Atoms Definition and 852 Threads

Anti-hydrogen atoms have been trapped/stored for the first time at CERN. http://newscenter.lbl.gov/news-releases/2010/11/17/antimatter-atoms/

If light travels through a perfectly transparent material, it will not be absorbed, and other than the reflection loss at the two interfaces, the energy that comes out will be equal to that which went in. Yet we know that the light field is causing all the atoms in its path to oscillate, thus...

Can we move atoms into any pattern we want? Thanks!

Homework Statement In a simple atomic model of a solid, the atoms vibrate with a frequency of 2E-11 Hz. The amplitude of the vibration of the atoms is 5.5E-10 m and the mass of each atom is 4.8E-26. Calculate the total energy of the oscillations of an atom. Homework Equations total...

How "Old" Are The Atoms In Our Body? Richard Feynman once said, "So what is this mind of ours: what are these atoms with consciousness? Last week’s potatoes! They now can remember what was going on in my mind a year ago — a mind which has long ago been replaced. To note that the thing I call...

Historically the experiment was performed on silver atoms, but what's the reason of using silver?

due to e=mc2 would massless photons and an equivalent number of mass-energy atoms have the same effects on gravity? Does mass play any special role in gravity or only energy?

I have a question that I couldn't find in my textbook. Say for example a hydrogen atom. If it is excited the electron will jump to a higher quantum level and as it relaxes it will release a photon proportional to the potential energy gained in the higher quantum level... My question is why...

Alright here's a question for everyone that has some input. Can we ionize atoms, say hydrogen, in free air? This is hard to explain, but can we make plasma in the regular atmosphere? Thats the only way I can word it. So is it possible?

In an argument of sorts with another college classmate, please help. We were argueing science and religion. She stated that all life is made up of atoms, and atoms are now shown to be made up of soundwaves also. Not possible correct?

I was just curious about atoms in biology. Do organisms have the same atoms all the time? Or are they always changing? When we eat do we gain new atoms etc. Sorry if this is a dumb question. I can't find anything on it maybe because it is to easy.

Hi guys, I wanted to know these things with their respective examples : 1. What is an atom ? 2. What is a particle ? 3. Why do we use/calculate the atoms of an element to balance an equation ? Please answer to these questions guys, because I only have 2 days for my exams and to know them.

Arginine has a molecular formula od C6H14N4O2 How many moles of C atoms are there in 0.47 mole of arginine What is the equation I would use here

Hi all. I was hoping you mat be able to help me with a question. If matter is made up of atoms, why do these atoms come together to form different matter? For example, why do some atoms form a brain whilst others form skin? How do these atoms know, if you like, what to form? Why do some...

How can I calculate the attractive electric force between the unlike atoms of a water molecule? Would I use Coulomb's law? Using Coulomb's law: I don't understand the radius I would use?

A quick question... When you excite electrons or so in molecules, atoms etc., do the molecule/atom change, or what does happen ? I mean, if you have water, and excite an electron, do it turn from "liquid" to "gas", or the other way around, or doesn't it change its structure or what you can...

In my computer science class my prof rambled off into examples, one of which was atoms. He said that atoms were just a model for something that we really can't understand yet. Is this correct or is he under some kind of influence or a complete idiot (likely, he teaches programming 'backwards').

"Moving Individual Atoms"? Hello; I recently read an article about this video - IBM moving individual xenon atoms to create the IBM logo. I'm not sure I understand what they're doing in this video - are they using a computer to simulate/show what this would look like if the atoms really...

hello I am very new to this stuff and i hear that atoms make up everything we know . but i was wondering about the atoms that make up our bodys do they come from what we eat and maybe the sun and we make them into what we need to grow and live ? or can completely new atoms be created within the...

Homework Statement In the absence of the Pauli principle, the Coulomb force would not be saturated, and the energy of a system containing N atoms would vary as N^(5/3). Show that a system of 2N atoms would have an energy lower than that of two N - atom systems. Homework Equations E...

If you placed an atom in an empty universe that was completely dark and cold, would it eventually radiate away all its energy until it had zero KE? If so, what would happen to an atom with zero energy? In this sense, are atoms inherently unstable systems?

How many hydrogen atoms are there in a 5 sample of pure hydrogen?

Homework Statement Minimal growth medium for bacteria such as E. coli includes various salts with characteristic concentrations of mM and carbon source. This carbon source is typically glucose and it is used at 0.2% ( a concentration of 0.2g/100mL). a) Make an estimate of the number of...

What caused it to suddenly create a universe? What caused the singularity to change into the Big Bang? Can anyone explain how all the mass-energy was accumulated into the "singularity"? Where did the Energy in singularity come from? Could it be that human cosmologists are only stating an...

So heat is vibration of atoms in lattice (or fluid). Heat is also electromagnetic radiation. Do we say "heat is electromagnetic radiation", or is that incorrect, since heat is vibration of atoms in lattice? Should we say "heat is __spread by__ electromagnetic radiation instead?

what determines what order the atoms in a formula are written? for example, why is it CO2 and not O2C? It doesn't appear to be ordered by atomic weight, place on the peridoic table or alphabetically so what is it?

Hey guys.i have heard it has been experimentally proved that even atoms can tunnel through a metal surface.I tried searching all over the web but just could not get any references on that.So,is that true?if somebody know where i can read more about that experimental proof,please point it out...

Why don't the electrons ever hit each other,and when they do what happens? Do the atoms sometimes have more electrons than protons because other electrons from other atoms come close to it and get caught in its orbitals?

Example: Take a hydrogen atom and make it a carbon atom. Can we do it with our current technology? If so, how do they do it?

Cant we see atoms?? In a book I read that theoretically it is not possible to see atoms even if high quality microscopes are used. So why is that?

[SIZE="2"]I'm not a science student. Therefore, please keep your reply simple and straightforward so that your help and guidance can be appreciated to the fullest. Thank you. I don't know if it's the right forum to ask this question. My question is not exactly about the origin of life rather...

Homework Statement a) Consider a sample of hydrogen atoms at a temperature of 300 K. i) What is the ratio of the number of atoms in the n = 2 energy level to those in the n = 1 level? ii) At what temperature would the ratio be 1/10? b) Assume that the conduction electrons in...

What's up everybody, I have a curiosity that struck me today and I figure some people here could probably provide some insight on. Today I was reading the book Broca's brain by Carl Sagan, and in it he pegs the number of atoms in a grain of salt to be around 1018. However, in the same...

As the title states, if I go to space and detect several atoms per square meter of space, does this suggest that the space between these atoms is essentially void of all forms of matter? Thus is this a perfect vacuum?

A balloon contains 0.40 mol of helium at 300K. calculate 1/ The number of Helium atoms in the balloon 2/ The average kinetic energy of the helium atom in the balloon 3/ The total kinetic energy of the helium atoms in the balloon I am having a lot of difficulties to manage the ideal...

Just for fun, I'm wondering if anyone knows what compound has the greatest number of different atoms. Even something as complex as DNA only seems to have five. But in theory you could have a molecule that includes the whole table! Seems like there's not much diversity in ordinary molecules...

I guess I'll take pot luck and ask another question here. I think I read somewhere that the current thinking is that the electron remains as a point or particle, even when it "orbits" an atomic nucleus. Yet I thought that deBroglie's contribution was that the electron is some sort of standing...

I was looking at sulfur hexafluoride and noticed that the sulfur forms 6 bonds with fluorine. Wouldn't 2 bonds put it at 8 valence electrons? How does it form so many extra bonds when it only needs 2? Edit: I should word this as "How does sulfur form 6 bonds with fluorine? Wouldn't that give it...

What happens to the atoms when they collide in CERN? They break down into their smaller parts I believe like glueons and other pieces, but do they stay that way or do they then recombine or what? Also do the same atoms, like 2 gold atoms, when smashed together always produce they same...

I would like to see how far I can get writing some novel & simplified simulator code for molecular modeling based on QM. ------ Background follows ---- skip to next post to get to the details of the project & starter QM question.. My son took chemistry this last semester (High-school...

Hi, Would anyone be able to explain the main differences between the effect of electrons and photons colliding with atoms in the ground state. As far as I understand they are very similar as both cause excitation and in some cases ionization. Any help would be greatly appreciated. Dave

The diagram (see attached) represents some of the energy levels for an atom of a gas. White light passes through the gas and absorption lines are observed in the spectrum. Which electron transition produces the absorption line corresponding to the lowest frequency; A. E3 to E2 B. E2 to E3 C...

Hi all,well my first questions, such a huge community, thanks to the admin/staffs for this making this forum :) How did the Hydrogen Atoms formed from the energy in the early universe ? like our DNA determines how we are built (just a sample approach), was there in the energy any...

According to my knowledge and understanding of things, mirrors reflect light perfectly because they are almost perfectly flat, or at least uniformly flat at most places. (\ and / are light rays) __\/__ But if all matter is composed of atoms, then a mirror would not be flat and would...

Do physicists say that atoms behave as waves just because they can't look at them directly so they have to use math to predict probable areas where they could be? or do atoms literally behave as waves?

Homework Statement How many atoms are contained in 15 litres of Ar at STP Homework Equations The Attempt at a Solution I just did 15/22.4 = 0.669642 0.669642 x 6.022x1023 =4.0325x1023 Is this correct. Thanks so much for your helo

Homework Statement 1. Homework Statement The temperature of the surface of a certain star is 8000 K. Most hydrogen atoms at the surface of the star are in the electronic ground state. What is the approximate fraction of the hydrogen atoms that are in the first excited state (and therefore...

I have a question which may seem stupid, but I think I missing something here. I see 2 equations describing allowed energies for electrons in hydrogenic atoms, being: E = -\frac{hcRZ^2}{n^2} And E = -\frac{RZ^2}{n^2} I assume that both are correct, but what makes the difference? Is it the...

I wonder if there is any theoretical knowledge how to predict which atoms will decay first in given radioactive substance? I was asking about this in school and teacher said it is not possible to predict this...i doubt this process is random... Thanks

Hi People all know that a neutral atom has no net charge. Well, does that mean that it neither creates an electric field nor is affected by any electric field? I wonder whether it's correct or not, because the distance between a test charge outside this atom is closer to its electrons...