What two factors determine whether a molecule is polar or nonpolar?
916020
Whether or not the molecule contains polar bonds and the geometry ( the 3-d arrangement) of the bonds in the atom.
361732
Lewis structure of CH2Br2\n\nIts identical to the lewis structure of methane but just replace two hydrogen atoms with bromine atoms (remember to add the three lone pairs around both bromine atoms).\n\nNow about polarity:\n\nThe C-Br bond is then considered to be polar. Having bromine slightly negative and carbon slightly positive. Over all the molecule is polar.\n\nSymmetry:\n\nAnd yes dibromomethane (CH2Br2) has two planes of symmetry, one horizontal and one vertical. In order to verify this, you have to look at the molecule in three dimension and not two dimentional (as drawn on a paper)
327842
I am pretty sure that it is due to polarity.  Since sulfur forms nonpolar S8 molecules, they are nonpolar, where water has a + end and a -end, making it polar (has a dipole moment).  The general rule is like dissolves like.  Molecules that a alike can interact on  the molecular level and form solutions, unlike molecules can not.
382554
It's not polar; It's ionic.\n\nBaO consists of Barium in the +2 oxidation state and Oxygen in the -2 oxidation state.
230448
dipole-dipole\nhydrogen bonds\nlondon forces\n\nde nada
899426
the way i like to look at is... in a given molecule, you usually have one or two (maybe three) central atoms.  for example, in CH3OH, the carbon is your central atom.  in C2H5Cl, two two carbons are your central atoms.\n\nnow, taking a look at the central atom, see if it is bonded to identical atoms an all sides.  For example, if the carbons are bonded to four idental atoms, then it is non-polar.  if the carbons are bonded to different atoms, then it is polar.\n\nIf you take a look at CH4,  there are dipole moments between the bond  between the carbon and hydrogen, but the molecule as whole is considered non-polar because the carbon is bonded to four identical atoms.  \n\nhope that helps.
596688
Becaue water is polar and water molecules form hydrogen bonds with each other.
382009
Oil and turps are nonpolar, water is polar. Those two types of molecules when mixed can't form solutions (ref.).
212143
polar...water molecules "stick" to each other so to speak...
726821
When trying to figure out what dissolves in what solvent, you have to consider POLARITY and remember the rule "like dissolves like".  \n\nSo a polar molecule will dissolve in a polar solvent.\nA nonpolar molecule will dissolve in ONLY a nonpolar solvent.\n\nWater is POLAR...we know that because of the structure of the water molecule haveing lone pair, being bent, and being able to have hydrogen bonding.  Ethanol is also POLAR because of it -OH (hydroxyl) functional group so it will dissolve in water.\n\nBenzene is NONPOLAR (chemists sometimes call it greasy) because it s made up of only carbon and hydrogen and is entirely symmetrical.  There are no electronegative atoms (such as F, Br, Cl, O, S) to cause a partial negative/positive to exist on the molecule so it WILL NOT dissolve in water.   It should dissolve in some NONPOLAR solvent such as hexane or diethyl ether.
159409
the rule of thumb is "like dissolves like" \nWater is polar so if it dissolves a substance, that substance is also polar.
912679
PCl3 has the same shape as NH3 (tetrahedral with P in the center, the 3 Cl at the 3 corners and a lone pair at the fourth corner) So the polar covalent bonds don't cancel out each other\n\nSO3 is planar trigonal and thus the dipole moments cancel out each other and it is non-polar\n\nCF4 has a tetrahedral shape and since all bonds are the same they cancel each others dipole moment;the molecule is nonpolar\n\nCH2F2 has the approximately the same shape as CF4, but since not all bonds are the same their angle is a bit different and the sum of the dipole moments is not zero; thus the molecule is polar\n\nSO2 is a bent molecule (because of the sulphur's lone pair), think of it in a way as water with S in the place of O and O in the place of H so it is polar.\n\nCO2 is a linear molecule (O=C=O) so the dipole moments of the two identical polar bonds cancel out each other; the molecule is nonpolar\n\nO=C=S has different polar bonds, so although they have opposite directions the result will be a slight dipole moment, so the molecule is polar.\n\nIn all your questions you have to compare a polar and a nonpolar molecule. Of course the one with the strongest dipole-dipole interactions in each case is the polar molecule.
132557
Acetone is a polar molecule (i.e. the centers of positive and negative charges in its molecule do not exactly coincide). It infact is more polar than the water molecule (2.91 D > 1.85 D). Due to this (and of course other reasons I donot know) acetone has a very good solvent action and finds use in industry primarily as a solvent - including its use as a nail polish (which contains nitrocellulose; acetone probably breaks this down) remover.
916756
non polar  \nit's linear in shape ,so the magnet moment equals zero \nthe lone pairs around the two O atoms \nevery O atom has 2 lone pairs\nthe central atom is C atom
35463
To have a net dipole moment (a positive end and a negative end), a species has to have some charge (partial or full) and have some asymmetry.\n\nMany (not all) ions are spherically symmetric (a metal ion, for instance--Na+).\n\nHowever, hydroxide ion (HO-) has asymmetry along the H-O bond, so it can have a net dipole.
734468
A molecule is said to be polar when the atoms are different in its electronegativity and its magnitude does not cancel off each other. Water itself is made up of Oxygen & Hydrogen atom. The electronegativity of o2 and h2 is the same. Thus, there are no dipole movement in the oxygen-hydrogen bond. However, the magnitude of the 2 hydrogen atom that is attached on the oxygen bond is in a 45 degrees manner. Thus, when the magnitude of the whole molecule is considered, the molecule is deemed to be polar.
837976
A molecule's structure can determine both chemical and physical properties of the compound (or element).  For example, the water molecule is asymmetric along one axis, making the oxygen atom side negative, and the hydrogen atom side positive.  The water molecule is said to be polar, and it will dissolve other polar molecules (and ionic substances) much better than non-polar molecules.  The molecule is also very stable, so water doesn't react chemically very easily - it doesn't burn, for example.