Find which has the stronger intermolecular dipole-dipole forces?
822762
Both CH3F and CF4 are tetrahedrons, but due to the substitution each has a different symmetry (C4v and Td respectively), as a rule the lower the symmetry the higher the polarity of the molecule. Actually, any Td (fully substituted tetrahedron), Oh (fully substituted octahedron), D4h (fully substituted square planar), D3h (fully substituted trigonal bi-pyramidal) will be non-polar molecules. This is due to the cancellation of the dipole moments.\n\nThus in order of the strongest dipole moment the answer is\n\nCH3F > CF4 (C3v < Td)\nXeO3 > XeO4 (C2v < D4h)\nSO2 > CO2 (C2v < D(inf)H)\nCOCl2 > BF3 (C2v < D3h)\n\nIf you are having a hard time understanding the Schoedinger group types, try a 3D modeling program (eg Spartan Build or ChemDraw 3D) to see the differences in the symmetry of the molecules.\n\nI hope that this helps. Please feel free to contact me if you have any further questions.\n\nKen
836698
The greater the Kb value is, the stronger the base.  Just think about what Kb means.  On the left side of the equilibrium is the base, on the right side is the conjugate acid, meaning the base has reacted.  The stronger the base, the more it will react, the more the reaction will proceed to the right, the greater Kb will be.\n\nSo.....\n\nC > E > B > A > D
1004425
The heavier the molecule, the slower it moves. The lighter the molecule the faster it moves.
121693
cmon...dont u know basic physics...just calculate the resultant of these 2 forces\nanswer= [(132)^2 + (181)^2]^1/2\nif this makes sense!!
72779
A molecule is made up of atoms.
89859
All molecules have intermolecular forces holding them together.  That is how we have things that are large enough for us to see.  Salt is held together by ionic forces.  Water by hydrogen bonds.  Acetone and ethyl acetate (found in nail polish removers) by dipole-dipole interactions.  Oil by van der Waals or London or dispersion forces (all the same thing).
927912
Bigger molecule means stronger intermolecular forces, and as a resault lower vapour pressure at a given temperature.
103986
The Hydofluoric Acid i.e. HF has the strongest Cationic Hydrogen Bond.\nAnd I think I fogot the Binding Energy of it\nNo Problem I will tell U Later when I Read my book
953238
It is true for individual bonds, but not for molecules.\nThe dipole moment of the molecule will depend on the geometry of the polar covalent bonds. E.g. CF4 has 4 polar bonds but they arranged so that the sum of their dipole moments is zero and the molecule has actually no dipole moment.
1138290
Look up stuff like Arrhenius equations. I don't have my phys chem text book to hand.\n\nFor part two, I think it's D, as I'm fairly certain it's not any of the others.
361166
Look at the electronegativity of both atoms. The electron density is going to be clustered around the more electronegative one. Electronegativity increases as you go up and to the right on the periodic table (noble gases not included), so Fluorine is the most electronegative atom.\n\nSo, the bond between nitrogen and oxygen is polar, but only slightly. The bond between iodine and fluoring is quite polar. The bond between cesium (the least electronegative natural element) and fluorine is so polar, that all the electron density is clustered around the fluorine, making it an ionic bond rather than a covalent bond.
482712
um...  subtract???  hahaha\n\nThe higher the differences in electronegativity, the more ionic the compound.  The higher electronegative atom/ion will want to "hog" all the electrons.  They are greedy like that.  They don't want to share (which would be a covalent bond).
848068
ICl2 + should be bent like water since I will have two lone pairs and two Cl's on it.\n\nI3- will be linear\n\nSbCl6- will be octahedral
478436
Intra>>>>>>Forces among atoms of the molecule.\nInter>>>>>>Forces between a molecule and its surrounding molecules.
728160
1. C, 2. Cl, 3. Se. The closer the atom is to Fluorine on the Periodic table (excluding noble gases), the stronger the electron affinity. Fluorine is the strongest.
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.
951079
b and d are not right.\n\nb. - going across a row the atoms get smaller so Co is smaller than Fe\nd  - Na is in row 3 and is larger than Be and Ne which are in row 2