Also what is happening to the size of electron orbitals?\nOr is the "expansion" only between discrete bodies?
209981
The expansion happens everywhere, but things that are bound together even moderately, do not experience it reletive to what they are bound to.  You don't notice it in the solar system, our own galaxy, or even the local galaxies near by.  This is because the gravitational force is enough to overcome the exansion.\n\nSimilarly you don't exapand (due to chemical bonds), and electron orbits, governed by QED (advanced form of electromagnetism) don't change their size.  In a sense you will only notice it with objects that you are basically unconnected with.\n\nWe don't notice the cosmic expansion until we either look at galaxies and objects very far away, or look at light that has traveled vast distanced before it reaches us.
410505
there are 3 orbitals in 2p subshell: ml = -1,0,+1\nit's just a fact.
478144
A) Valence Electrons\n\nI believe b, c and d show the results of the grouping not the reason they're grouped that way to start out with...\n \nb... No... The atom size increases instead of decreases\nc... No...\nc... No...  \nversa...
115540
The concepts that we cling to suggest that protons and electrons are particles that occupy a finite POINT in space. The truth is that this is a good picture to use to fit the kind of world we see outside the atom. But in fact we only know that the effects of electrons appear to come from one location, and that location (of the effects) seems to change with time. Therefore we say the particle (electron) moved.\n\n Regarding the nucleus and the protons and neutrons, it is difficult to picture stationary objects packed so closely together, particularly since the protons are repulsive to each other and since strange events periodically erupt from within most of them - sort of analogous to groups of people from opposing schools required to mingle at a party, but never allowed to group together with their friends. Occasionally a fight breaks out and someboby is pitched out the side door or window. Again at the site we identify with the particle, all we know is that there are electric and magnetic field characteristics emanating from the "site" where we say the particle resides. If the essence of the fields move, we say the particle moved.\n\nSo what is an electron? All we know is that there is an electric and magnetic field disturbance together with a phenomenon we call mass (gravitational emanations), that changes in location with time. That there is a central location for the emanations allows us to specify a spatial position for the particle.
476557
hey, when you have 2 electrons in the same orbital, you will always have one spinning up and one spinning down... its about balance, if both electrons were spinning the same direction, they could not stay in they're orbits...
145002
It is just a reference to E=mc^2.  It can be through fission or fusion, so yes you are surely correct.
549782
alright. Electron configurations. I had the exact same problem three weeks ago. I was SO confused. But i got it in the end.\n\nLet me explain.\nThere are two types of electron configurations. One is the simple electron shell configuration. Let's say 2-8-16 and the other is called spdf notation like 1s2 2s2(i can' t type the two after the s like an exponent so bear with me)\n\nNow the first one is simple. Shell notation. An atoms outer shells are divided into shells that each have a maximum limit for the number of electrons that they can contain. the first can hold 2, the second 8 and so on. They all follow a rule. It is always 2 time the shell number squared. lets say level 1. Square it. You get 1. Multiply it by 2. You get 2. Therefore 2 is the maximum # that level one can hold. You said 15. So fill each level so that each contains the max. It would be 2-8-5. (The last one is five so that the all ad up to 15). Got it?\n\nNext, we have spdf notation. This takes a lot of time to explain so i'll just give you a site to go to. \n\nhttp://www.fordhamprep.org/gcurran/sho/sho/lessons/lesson36.htm\n\nGood luck!
394740
WHOA! WHOA!  Those guys are wrong.\n\nThe answer is "C" - ionization energy increases.\n\nLeft to right is:\n1) more non-metallic character\n2) increasing electronegativity\n3) increasing ionization energy\n4) decreasing atomic radius\n\nOf course, Fluorine is the most electronegative (4.0) of all the elements.  This means it is going to hold its electrons very tightly.  Since it holds it's electrons tightly, it is going to be difficult (require lots of energy) to ionize it.  Also, because it holds its electrons tightly, they are in close, so that is why the atomic RADIUS decreases L to R as well.\n\nNOTE:  I think "Mr Warlord" below is the one who really doesn't understand.  He thinks that the electrons from another element are different than the ones around Fluorine already.  AN ELECTRON IS AN ELECTRON, BUDDY.  How is the Fluorine going to do differentiate between electrons?  It just pulls them close whether it's on it's own or in a covalent bond.  An attraction to an electron is an attraction to an electron (electronegativity) and an electron is an electron.  GROW UP AND LEARN SOMETHING BEFORE YOU CRITICIZE.  Look it up in a textbook and post back.
209152
As you go down, the electrons occupy energy levels whose energy is greater. That is, they are farther away from the nucleus. For example an element in period 6 has its outtermost electrons in the n=6 energy level. These electrons have a greater potential energy than those in the n=2 level because they are farther away from the nucleus. This is similar to an object that is higher up: It has a greater gravitational potential energy. The size of the atom increases because as more electrons are present in an atom, the more energy levels they fill. The outtermost occupied energy level of an atom is what determines size.
102973
Atoms do have empty spaces but these spaces are according to their size not ours let me elobrate first that we are not composed of atoms we are composed of cells if any one says atoms then tell that person that atoms are non living whereas cells are living some part of our body are dead cells like nails hairs dead skin at the knuckles etc but the rest is all living cells.\n\n\nThings don't fall through other things because they are levitating on an electrostatic field! I am not kidding! When you sit on a chair, you are not really touching it. You see, every atom is surrounded by a shell of electrons. This electron cloud presents a rather negative face to the world. Remember that like charges repel each other. When two atoms approach each other, their electron shells push back at each other, despite the fact that each atom's net charge is 0. This is a very useful feature of nature. It makes our lives a lot easier.\n\nNow the question you should be asking is, if atoms push away from each other, why doesn't the entire universe just blow away from itself? The answer is that some, actually most atoms' electron shells are not full. When two atoms come together and have empty spaces in their electron shells, they will share electrons to fill in the spaces in both of their shells. Yes, the electrons really do go back and forth between atoms and they do so pretty fast. Electrons tend to be kind of mobile, which is also a very nice feature of nature, since without it your walkman would not work. Once both atoms' outer shells are full due to this electron sharing, they go back to their usual repulsive behavior. This, by the way, is how we get molecules and the secret to understanding Chemistry. It's all about the electrons!
280056
(a) Across the row (called the Period), the magnitude of the 1st IE increases. At the stage where we label an element as a non-metal, this value is too high for the outermost electrons to be lost, so instead of Oxygen with a charge of 6+, it actually gains electrons to obtain the stable structure; i.e. oxygen with a charge of 2-.\n\n(b) Down the group, the size of the atom increases due to an increase in the number of shells. Due to this the outermost electrons (-ve) are further away from the nucleus (+ve) and so the 1st IE decreases.
450724
The size increases because the electron orbits add up as you go down the group.
17022
1. The Aufbau principle: Orbitals are occupied in order of increasing energy. 1s<2s<2p<3s<3p<4s<3d<4p<5s<4d<5p<6s<4f<5d<6p<7s<5f<6d\n\n2. The Pauli exclusion principle: Only two electrons can ocoupy an orbital and they must have opposite spin.\n\n3. Hund's rule: When there are degenerate orbitals, one electron is added to each with their spins parallel until all are half full. Then a second electron with opposite spin is added to each degenerate orbital. (See below)\n\n(Basically every space/box/circle must have an arrow pointing up before any space/box circle can have one pointing down.)\n(Everyone gets one before anyone gets two.)
395928
The only way to accommodate additional pairs of electrons is for the central atom to use its empty outer d orbitals in addition to its occupied s and p orbitals. Therefore, expanded octets occur around a central nonmetal from Period 3 or higher, those in which d orbitals are available.\n\nS, Cl, F
165403
I see it this way, when and atom it's close to get his 8 covalent electrons, it' easy for it to attract more electrons (It needs less!), that's why the last column it's practically inactive, their outer atoms are fulfilled already
625250
First I will address your difficulty with the answer someone gave to your earlier question.\n\nSpace is expanding between distant parts of the universe, and presumably very slowly on local scales too (~100 km/s per MPC, works out to about 100 nm/s over a distance of a meter.  Hmmm, I wonder if one could devise an experiment to measure that. . . )  \n\nLocally, things like gravity (in the case of a galaxy) or electromagnetic forces (in the case of a less than planet sized solid) overcome that expansion. If everything in space was expanding uniformly, we would never notice that phenomenon, because the "rulers" we use to measure distance and size would be expanding too! \n\nSo, you can throw your baseball, and maybe space will expand between the two of you as it travels, however the friction between the two of you and the ground, and the chemical bonds and electrostatic forces in the strip of ground between you and your dad do not permit the two of you to be dragged apart by the expansion of space during the ball's travel time, just as those same forces prevent your body from expanding with the expansion of space.\n\nThe answerer was incorrect in their generalization. I will take a look at this earlier question you asked; in context the part of the answer might be OK, but it appears to be too general a statement the way you presented it.\n\nKeep questioning answers;  you have the makings of a good scientist, philosopher, lawyer or other combination creative and analytical  endeavour.\n\nYour more general question was about movement in "space-time." If you define movement by a change in space-time interval, then the difficulty is in staying still!  In fact, you have to move through 3-D space at the speed of light to experience zero change in the space-time interval between two events; only light itself is frozen in space-time in those terms.\n\nWiki has a good section on space-time intervals:\nhttp://en.wikipedia.org/wiki/Space-time_interval#Basic_concepts
407522
i can assure you that  the answer is \n\nA. the Bohr model of the atom, with discrete orbits. \n\ni have been analyzing this work  for 3 years.\n\n\np.s the answer is so funny C."C. the Einstein model of the atom."