The Vietnam War (1954-1973) was a very long and costly war in which over three million people lost their lives. The United States became involved in the war to support their allies in South Vietnam. The U.S. and South Vietnam were fighting against the communist regime known as the Viet Kong.
Ion-dipole interaction (dipole-ion interaction): A noncovalent attraction between one pole of a bond dipole and an oppositely-charged ion. The Î´+ end of the bond dipole is attracted to an anion, and the Î´- end of the bond dipole is attracted to a cation.
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.