Si,Cl,Rb,Ca,S is the most electronegative?
337603
Here is the answer.. Just remember periodi table...\nElements on left most side are electro positive and elements on right most are electro negative. (The last row is nobel gases..so leave it)\nNow Cl- belongs to right most side... its more electro-ve\nRb, Ca are on left side.... they are electro positive(They will give  electron with out much force)\nSi, S are in middle-- their properties are in between...\n\nThats it!
1187752
d)O and Cl. They have the least difference in electronegativity, so the shared pair of electrons is not drawn particularly towards any atom. Thus the molecule shows the least ionic character. Ionic character occurs when there is polarisation of a covalent bond.
811889
No concrete way to work it out. Groups one and two take positive charges equal to their group number (Mg2+, Li1+ etc). Groups 3, 4, 5, 6 and 7 ionise to a negative charge of 8 minus their group number (Cl1-, O2- etc), though 3, 4, and 5 tend to resist ionisation and are much more commonly found bonded covalently. The Transition elements ion charges are virtually impossible to predict without an extensive knowledge of d orbitals etc..
649164
Francium and cesium are about 0.5.\nFluorine is highest at 3.9-4.0 (by Pauling's estimate)
76628
By "shells," do you mean the energy levels of the electron orbitals?  If that's what you mean, all you do is look on the period table and count how many rows from the top the element is.  So H and He each have one electron shell, C, N, O, F, etc. all have two, Si, B, Na, Cl, etc. all have three, and so on.  Sorry about the scattered examples (I was listing them by memory), but hopefully you get the idea.
100646
Trichloromethane (CHCl3) as a) it is asymmetrical & b) the electronegativity of the Cl 'pulls' the eletron density away from the C-H bond
837624
Cassandra C has given you a very good answer.\nYou are interested in a single type of reaction: single displacement. It is a redox reaction so you have to think which compound is more happy having extra electrons (more electronegative).\n\nIn the case of A+BX-> AX + B, B(+) in BX is a cation and is missing an electron. If B is a more electronegative negative element than A, then it will steal away the electron from A and the reaction will occur. If A is more electronegative then B is not "strong" enough to steal the electron and the reaction will mot occur.\n\nIn the case of Y+BX -> BY+X you have the opposite. X(-) in BX has already an extra electron. So if X is more electronegative than Y it will not give away the electron and the reaction will not occur.\n\nThis is an oversimplified reasoning. The proper one is that you have to look at the standard reduction potentials (E0) which give the reactivity series. The half-reaction with the highest reduction potential will be the one favoured or more correctly the reaction will occur if the redox potential of the whole reaction is positive.\n\nFor instance you can find a detailed table at\nhttp://www.northland.cc.mn.us/Chemistry/standard_reduction_potentials.htm\n\nLet's see your reaction\nCu+FeSO4 -> CuSO4+ Fe \nIn this case the half reactions would be\nCu - 2e -> Cu(+2)\nFe(+2) +2e-> Fe\n\nFrom the website we get that for\nCu(+2) + 2e->Cu  E01=+0.342 Volt\nFe(+2) +2e-> Fe E02=-0.447 Volt\n\nE01 is more positive than E02 thus Cu(+2) tends to get electrons from Fe and not the other way around so the reaction will not occur \nOR\nYou find the E of the reaction like this.\nThe second half-reaction is in the form we want it. The first is in the reverse. So we just reverse the reaction and the sign for the potential\n\nCu -> Cu(+2) +2e E01'=-0.342\nFe(+2) +2e-> Fe E02=-0.447 and add\n\nCu + Fe(+2)+2e -> Cu(+2)+ Fe+ 2e with E=E01'+E02= -0.342+(-0.447) \n\nTherefore Cu+Fe(+2) -> Cu(+2) + Fe E= -0.789<0 and so the reaction will not occur.
68791
Reactivity in goup 1 increses down the group from Lithium to Sodium to Potassium. Therefore, Sodium would the closest. They are all group 1 metals, just in different periods. All have one vacant electron which makes them very reactive.
112370
H2S.  That's very similar to H2O (which we usually associate with H-Bonding).  HBr, HCl, and HF will ionize.  SiH4 is symmetric and Si has medium electronegavity, etc, such that it would be like methane (Si is in the same group as C).
452453
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.
201939
a.)ionic b.)covalent c.)covalent d.)metallic
1094317
aluminium because its an alkali earh metal and\nfluorine is a halogen
596849
2 - Potassium Chloride\n\nIt has, by far, the weakest covalency of all those listed, and therefore breaks apart most readily.
940983
I believe it would be:\n\nNe\nCH3Br\nCH3CN\nCH3OH\n\nthe -OH is the strongest of these because of hydrogen bonding
546448
this polar nature depends on electronegativity. \nIn a bond, say C-H, the most EN element gets partial -ve charge and less EN element gets partial +ve charge\nIn C-H, H is less EN and C is more EN. Thus, C gets partial +ve charge and H gets partial -ve charge.\n\nEN of C is 2.550 EN of H is 2.200\nEN of Si is 1.9 EN of Sn is 1.96\n\nIn this group EN of C is high and H is less in C-H thus, C-H is most polar. \n\nAs EN of Si and Sn is less, than H , H gets positive charge but very less +ve charge. but in C-H C is more EN and gets +ve 2.550.\nHope i was clear enough.\nAny doubts you can ask further.
178276
Gain one/two electron(s):\n\nIf an atom or ion acquires another electron in a chemical reaction, it has gained an electron.  ditto for two electrons.\nExample: S has 16 electrons.  If it gains one electron it becomes a S- ion.  If it gains two electrons, it becomes a S-2 ion.\n\nSteal one/two electrons:\nIf an atom or ion looses an electron in a chemical reaction, it had to go somewhere.  That "somewhere" will be to another atom/ion.  So, the receiving atom/ion could be said to have stolen the electron.  Same goes for reactions involving two electrons.\nExample: Na reacts with Cl to produce NaCl.  Cl "steals" an electron from Na, creating Na+ and a Cl- ions.\n\n"Never ever react electron"\nI have never ever heard this phrase.  Maybe it refers to a species (atom or ion) that does not participate in the reaction.  It's valence electron(s) would not react.
749219
a) Ag2S\nb) SnCl4\nc) Na3N\nd) SrI2\n\nDo us a favor and pay attention during class. That way you'd know how to do these.