Why is water considered a polar molecule?
956124
Not only does the electronegitivity difference between the hydrogen and oxygen exist, Its "bent".\n\nOn a water molecule there are 4 electrons not involved in bonding the hydrogen's to the oxygen, those electrons repel the hydrogen and push them closer together. This means it is not a straight line like H-O-H. If it were a straight line it would be non polar because the electronegitivity difference between the 2 hydrogen's and the oxygen would cancel out.\n\nIt is inorganic because it doesn't contain carbon. All organic molecules contain carbon.
554160
A molecule is polar when it has a dipole moment that does not cancel out. For example, consider the molecule CH4 (methane) which is nonpolar. It has a carbon atom bonded to 4 hydrogen atoms. Bonding is the overlap of the electron density. So you have an electron from a hydrogen and an electron from the carbon forming each of the bonds. Carbon is just very slightly more electronegative (tendency of pulling electrons closer to itself) than hydrogen. This means that the electrons are pulled by carbon away from hydrogen, but not by much (the difference is very very small). This shifting of electron density allows for the carbon to be slightly more negatively charged and hydrogen slightly electron deficient. This makes the C-H bond just slightly polar. However, because there are 4 hydrogen atoms that are bonded to the carbon, this bond polarity cancels each other out...meaning that the bonds are slightly polar, but the overall molecule is nonpolar. \n\nTo determine if the bonds are polar you just have to know the electronegativity differences. To know if a molecule is polar, you must know the correct geometry. Since electrons are negatively charged and repel each other, they want to be as far away from each other as possible. If you have a carbon bonded to 4 hydrogens, you will have a tetrahedral geometry with the hydrogens 109.5 degrees apart from each other creating the best possible arrangement. Also, if you have a lone pair of electrons, then the molecule will always be polar because of that charge separation.
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.
234734
firstly, a water molecule,H2O, is a polar covalent compound.or, the oxygen and the 2 hydrogen atoms have a difference in their electronegativities.\n\nthis results in the oxygen atom pulling the shared electrons towards itself.since electrons are negatively charged, a polarity is developed between the atoms. the oxygen atom has a slight negative charge while the 2 hydrogen atoms have slight positive charges. \n\nsince opposite charges attract, this will obviously result in the oxygen atom of one molecule to be attracted to a hydrogen atom of another molecule and vice versa.\n\nwhen water is in the liquid state, the molecules have a lot of kinetic energy, and because the charges are so slight, the molecules have enough energy to overcome a fixed sorta bond between them.many H atoms are attached to one 0 atom, and this results in more density.\n\nwhen in solid state, or ice, the molecules have lost their kinetic energy and hydrogen bonding comes into the picture. since a water molecule is a V kinda shape, and two ends are H atoms, a lot of space is required to get a complete, closed link of water molecules.so, many clumps of '0' shaped 'links' like this are formed.\n\nsince the water molecules have spread out so much in the solid state[due to hydrogen bonding] ice occupies more spce than liquid water.
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.
1067427
Hydrogen bonding of Water molecules: Due to the polar covalent bonds that hold a water molecule together, Hydrogen bonds form where the negative Oxygens and the positive Hydrogens are located.\nThe results of these bonds are as follows:\n \n1. Cohesion: is the sticking together of similar molecules. Water is very cohesive. This allows water to be pulled along a pathway with relative ease.\n \n2. Surface Tension: cohesion allows water to pull together and form droplets or form an interface between it and other surfaces. The measure of how hard it is to break this interface is its surface tension.\nWater allows materials to rest upon it if the surface tension is not broken. Pollen, dust, water insects, and other biological materials are able to remain on the surface of the water because of this tension.\n3. Adhesion: The sticking of one substance to another. Water is a good adhesive. It will cling on to many objects and act as a glue. Capillary Action is an example of cohesion and adhesion working together to move water up a thin tube.\n\n4. Imbibition: The process of soaking into a hydrophilic substance. Water being taken into a sponge, into a seed, into paper towels.\n\n \n5. High Specific Heat: Specific heat of a substance is the heat needed (gained or lost) to change the temperature of 1g. of a substance 1degree Celsius. Heat is the total quantity of kinetic energy due to molecular motion. Temperature measures the intensity of the average kinetic energy of the molecules.Heat and temperature are not the same thing. A Kilocalorie or large C equals 1,000 small calories.It takes 1,000 calories to raise 1,000g. of water 1 degree C. Nutritional Packaging has the calorie measurements in Kilocalories. One gram of Protein = 3 calories. This means 3,000 small calories or 3 Kilocalories.\nThis high specific heat allows water to act as a heat sink. Water will retain its temperature after absorbing large amounts of heat, and retain its temperature after losing equally large amounts of heat. The reason for this is that Hydrogen bonds must absorb heat to break. They must release heat when they form.The Ocean acts as a tremendous heat sink to moderate the earth's temperature.\n \n6. High Heat of Vaporization: Water must absorb a certain amount of additional heat to change from a liquid into a gas. This extra heat is called heat of vaporization. In humans, this value is 576 cal/g. This results in evaporative cooling of the surface. Alcohol has a value of 237cal/g. and chloroform 59cal/g.\nAs one can see water removes much more heat from a surface upon evaporation than does either alcohol or chloroform.\n \n7. Freezing and Expansion of Water: Water is most dense at 4 degrees C. At ) degrees C. it is 10% less dense. Ice floats because maximum Hydrogen bonding occurs at 0 degrees C.\n \n8. Versatile Solvent: Water is a major solvent in nature. When water and another substance is mixed the resulting solution is called an aqueous solution. Any solution contains the following parts:\nSolute( what's being dissolved) + Solvent ( what is doing the dissolving) = Solution.\nSolute Concentration: The concentration of the dissolved materials in relation to the solvent. This is always measured in moles. A mole is the amount of a substance whose mass is in grams is\nnumerically equivalent to the molecular weight in daltons. One must first find the atomic weights of the substance involved and add them together for the representative molecule and change the value to grams.\nMolarity occurs when the mole (gram atomic weight of the substance) is placed in a container and dissolved in one Liter of water.
499459
A very good question.\n\nAlmost all common chemical will contract upon freezing, but not water. \nThe special hydrogen bonding that forces the water molecule to be very close to eacher other in liquid phase.\n\nThe molecule of HOH is not straight, but in a V shape. About 105 degree.\nIn liquid phase the V shape can over lap each other. Go look up the water structure at\nhttp://www.chem1.com/acad/sci/aboutwater.html\n\nDuring freezing, the water molecule are force to line up, and the V shape molecule are line up side by side and no longer over lap.  This takes more room. So it expands.\n\nGo look up the ice molecule structure at http://www.uwgb.edu/dutchs/PETROLGY/Ice%20Structure.HTM\n\nIts not easy to see the true structure, but these will at least gives you a picture.\n\nKeep asking questions, enjoy.
166529
Why is H2O a liquid at room temperature as opposed to other similar molecules? Well, it is mostly to do with the difference in electronegativity between the Hydrogen atoms and the Oxygen atom.  Since there is a sufficient difference, this causes the molecule to be polar.  The Oxygen in one water molecule affects the hydrogen atoms in another molecule.  This bonding, since it's unusually strong, (yet not an ion) is called hydrogen bonding.  The network of interactions between the hydrogen and oxygen atoms creates the necessary attraction to hold a group of water molecules together in a loose formation (ah as in a liquid).  This occurs at a low enough temperature and just the right pressure.  Any less pressure, the attraction between the water molecules would be insufficient to maintain water as a liquid and it will boil away.
942020
We've to get this clear first. Water is a polar solvent, gasoline is a non-polar solvent. By the principal of like-dissolves-like, polar molecules will dissolve in water, for example, NaCl; while non-polar molecules will dissolve in gasoline, for example, fats, phosholipids, alkanes, alkenes etc.\n\nFor the question you've asked,\nChloroform is a polar compund because Cl draws electrons from the carbon center and making Cl atoms have a higher concerntration of electrons. Hydrogen atoms in water carry a partially positive charge and hence are attracted to Cl molecule. Hence it is soluble in water.\n\nNa2SO4 is soluble in water. This is because it is actually 2 Na+ ions attached to SO4(2-) ions. Na+ ions get attracted to oxygen atoms in water which has a partially negative charge and SO4(2-) ions gets attracted to hydrogen atoms in water which has a partially positive charge.\n\nKCL is soluble in water because Cl atoms draws electrons from K. Follow the same reasoning as chloroform.\n\nFor BaSO4, it is insoluble in water. Only barium nitrate dissolves in water. Other barium salts do not.\n\nHope this helps! =)
54989
Because as a neutral atom, it is not polar, and water is a polar solvent.  Sulfur is more soluble in nonpolar solvents like hexane or benzene.
755809
the shape of the molecule of the water is non linear because of the two lone pairs in C atom, therefore the shape of the molecule is non-symmterical. In a non symmetrical molecule, bond dipoles do not cancel out (although bond is polar) so overall, it's polar...\n\nin the case of water, the shape of its molecule is linear with double bonds. There are no lone pairs that will repel the other element, therefore the shape of the molecule is symmetrical. Dipole bond cancel out in the symmetrical molecule so the it does not become polar overall.\n\nsorry i don't know the answer to your second query...
1051142
because water molecules are heavier than air molecules.  If you think about it, these heavy molecules are weighing down (even though they are suspended) on everything around them  with more force (which is proportional to the mass).
181496
Even though water is polar and benzene is nonpolar, a very small amount of each will stay suspended in the other. Dry benzene is simply benzene with all traces of water removed.
820429
Hydrogens in water have a small positive charge, and oxygen molecules have a small negative charge...this is due to the higher electronegativity of oxygen compared to hydrogen...\n\nThis results in attraction of the positive and negative charges of different water molecules, resulting in what is called hydrogen bonds
119086
The molecules of water are closer together and constantly moving, whereas the molecules of ice are in a crystal lattice, meaning they're in a rigid formation. When water freezes, the molecules spread out a little more to form the crystal lattice. Since density is mass over volume, and ice has takes up more volume than water, the density of ice is lesser than that of water. Which makes ice float on water.
316023
intermolecular polarity and the fact that fluids dont compress the way gases do?
913933
Because of the covalent bonds between water molecules. Because water's polar, the molecules are very attracted to each other. It's important because it allows for things such as capillary action, which can be seen in plants absorbing water through their roots and having the water "climb" up the plant against the force of gravity.