like do u use the electronegativity chart and if you do then what
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No, we don't use the electronegativity chart; instead we draw the full structure of the molecule and then see which 'pulling of bonds' cancel each other. \nIn the molecule AsF3, since As has 5 outer most electrons(in group 5), each F is bonded to As with a single covalent bond. Hence, the shape of the molecule becomes trigonal pyramidal, with 3 bond pairs (with 3 F atoms) and 1 lone pair. The 3 bond pairs pull the electrons towards themselves in the lower plane, while the 1 lone pair pulls at the top. The pulling effect of the 2 F atoms at the 2 sides cancel out  because the pulling effect is the same for both F atoms; however, the pulling effect of the lone pair at the top and the 1 F bond pair at the bottom will not cancel, because it is not from the same atom/species. Hence the overall dipole moment( dipole moment = charge x distance) does not cancel out, so the molecule is polar, with some charge distribution remaining due to the unequal pulling effect.\n\nIn CF3Cl, the shape is tetrahedral, with the 3 Cl atoms and 1 F atom bonded by single covalent bonds to the central C atom. The bond pairs spread out with the 3 Cl atoms pulling at the bottom and the 1 F atom pulling at the top. The pulling effect of the 2 Cl atoms at the sides cancels out, but that of the F atom at the top and the Cl atom at the bottom does not, as the pullin effect of 2 different atoms is different. Hence, as before, overall dipole does not cancel and the molecule is hence polar.
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ok. To tell which elements are more metallic then others, It depends on the left over valence electrons that are attracted to the positively charged cations in a metal. To tell which elements are more active then others it is towards the right of the periodic table. Noble gases are non-reactive. To tell which atoms are bigger then others remember going from top to bottom in a group, atomic size increases, going from left to right across a period, atomic size decreases.(there is a pattern to this). \nI think if there are more valence electrons, the stronger the metallic bond is.
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check this link-- http://www.orgsyn.org/orgsyn/prep.asp?prep=cv6p0468.\n\ninstead of Me use Ph
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First off, I don't do people's homework, so I'm going to try and "lead" you in the right thinking direction rather than just hand you the answer.  My suggestions follow, using the number of your questions above as reference.\n\n1.   Re-read  your sulfur chemistry\n\n2.   Two words:  electron density.   Two more words:  Dipole moment\n\n3.   There's an electron (lone) pair that you've forgotten to account for...\n\n4.    See #3.  Extra electron pair on the N\n\n5.    Should be easily reproducible diagrams in your text.  Open it.\n\n6.    Several.  Start with my answer to #2.\n\n7.    Yes, if it contains an induced dipole.\n\n8.    Absolutely.  Example:  Carbon tetrachloride\n\n9.    Determine the electron configuration and then address the\n       definition of "paramagnetic" or "diamagnetic"...
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Electrons in the outermost shell are called valence electrons.\n·  It is the valence electrons determine an atom’s chemical properties.\n·  Electrons in the inner shells are inner electrons or core electrons.\n\nThe total number of electrons is revealed by the atomic number:\nNa - At#:11 valency:1 valency electrons:1 core:10\nSe - At#:34 valency:2 valency electrons:6 core:28\nPb - At#:82 valency:4 valency electrons:4 core:78
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You will have to first find the standard enthalpy values of the reactants and products. They're given in the appendices of any standard GenChem or PhysChem books.\n\nThen, you subtract the sum of enthalpies of reactants from the sum of enthalpies of the product to get the enthalpy of the reaction.
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Do a poster with charts of molecules, their chemical formulas, the masses of the elements in the formulas and how to derive their moleculare mass.  Then do a flow chart with the coversions between molecular mass, moles, particles and volume at STP.
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Refer to IUPAC's web site iupac.chemsoc.org or search on Google.
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OK, but you need to look up atomic weights or calculate molar mass.\n\n   Grams = Moles x molar mass  OR  moles x atomic mass\n\n    Moles = Grams/(molar mass) OR Grams/(atomic mass)
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go to inorganic industral chemistry book
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http://www.elements.nb.ca/index1.htm\nhttp://www.chem4kids.com/files/elem_intro.html\nhttp://www.chemicalelements.com/\nhttp://aleph0.clarku.edu/~djoyce/java/elements/toc.html
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lewis dot structure shows the molecule's valence e-s and the bonding of the molecule \n\nit is very easy to draw \nhere are some hints for drawing lexis structure\nfirst you need to find out the valence e-s of that molecule i.e. h2O have 8 VALENCE e-s 2 from the hydrogens abd 6 from oxygen \nthere is is Carbon present in a molecule than carbon should be placed in the middle  if there is no carbon present than least electronegative atom should be in the middle \nput one or two or three pair(s) of electrons in the middle depending on the octet rule which states that all atoms want 8 valence e-s other than H, Be, and S. H bond to get 2 valence electron, Be bonds to get 6 valence e-s and S can get more than 8 valence electrons \nif you are confused or need help with any of the models just email me i will try my best to reply
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analize an existing polymer with as many properties of the ones you are looking for, determine the formula ( possibly use a mass spectrometer for the recipe,)  experiment with the atomic structure of the elements in the formula. wouldn't it be great if you could manipulate the structure at subatomic level, i.e. at levels below protons and neutrons like quarks.\ntry changing the formula ( recipe?) at its basic level, with different proportions of at least carbon and hydrogen, possibly adding 'alloying' elements into the atomic structure.
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okay. i just took the test on this and passed with a B. so i promise i know what im doing.\n\nK, look at your elements. then look them up on the periodic table. lets pick, oh say the compout Cl(subscript)2O. that is 2 chlorines, and 1 oxygen. well, chlorine is in group 17, which means that each have 7 valence electrons, and oxygen is in group 16, which means that it has 6 valence electrons. following me so far? okay, take those valence electrons, and add them up. that equals 20 valence electrons. now, position the lewis dot diagram so that the oxygen is between the two chlorines. now, distribute the 20 electrons amongst the three letters, so that each has eight. now each letter should be surrounded by exactly eight dots. keep in mind that it should look like this -- :Cl:O:Cl:, but dots on the tops and bottoms. that is the lewis dot. luckily, this one did NOT have double or triple bondage. but in the event of double bondage, it might look like this -- :Cl::O:Cl, without dots all the way around each letter.\n\nand the VSEPR theoryis quite simple. it is just talking about the potential shapes that chemicals can make. for example, there is linear, or trigonal planar, or tetrahedral. this is vital. i promise that, if you contact me, i can give you a simple cheat sheet (not really for cheating, but it helps your memorization) to remember VSEPR. it gives you the shapes, lewis dot examples for the shapes, and angle measurements.\n\nhope this helps!\n~ally
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You first need to Draw the elctron configurateion for Each Element.  Then simply count how many unpaired electrons there are.  \n\nI drew a diagram for you: http://server6.theimagehosting.com/image.php?img=untitled2.145.JPG\n\nSulfer = TWO unpaired electron\nArgon = ZERO / NONE unpaired electron
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you can also write 1s2 2s2 2p4, for instance. In this way you are telling the number of electrons in each energy level (orbital), being 1s, 2s and 2p in this example the orbitals and being the number at the right the quantity of electrons there.
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Do you have a chart indicating the electronegativities of atoms?\n\nThe more electronegative atom will be at the point of the arrow.\n\nH has an EN value of 2.1 and Br has an EN value of 2.8.\n\nSo, in this case, the point of the dipole arrow points to Br.