When a tortilla alone can run you 300 calories, and a dollop of sour cream about 115, staying under 1000 can be challenging (forget about adding chips and guacamole). The Times found that just 25 out of 1,200 burritos fell below 700 calories.
the hydrogen atom attracts electrons much more strongly than the oxygen atom. water has two hydrogen atoms covalently bonded to a single oxygen atom. the oxygen atom has a greater attraction for electrons than the hydrogen atom does. water dipole moment is equal to zero. the electrons of the covalent bond are not shared equally between the hydrogen and oxygen atoms.
HCl molecules, for example, have a dipole moment because the hydrogen atom has a slight positive charge and the chlorine atom has a slight negative charge. Because of the force of attraction between oppositely charged particles, there is a small dipole-dipole force of attraction between adjacent HCl molecules.The dipole-dipole interaction in HCl is relatively weak; only 3.3 kJ/mol.(The covalent bonds between the hydrogen and chlorine atoms in HCl are 130 times as strong.) The force of attraction between HCl molecules is so small that hydrogen chloride boils at -85.0 o C. Dipole-Induced Dipole Forces.nduced Dipole-Induced Dipole Forces. Neither dipole-dipole nor dipole-induced forces can explain the fact that helium becomes a liquid at temperatures below 4.2 K. By itself, a helium atom is perfectly symmetrical.