The symptoms of influenza (flu) appear suddenly and often include: 1  Fever of 100.4Â°F (38Â°C) to 104Â°F (40Â°C), which can reach 106Â°F (41Â°C) when symptoms first develop. 2  Body aches and muscle pain (often severe), commonly in the back, arms, or legs. 3  Headache. Pain when you move your eyes.
A chemical bond is an attraction between atoms that allows the formation of chemical substances that contain two or more atoms. The bond is caused by the electrostatic force of attraction between opposite charges, either between electrons and nuclei, or as the result of a dipole attraction. double bond between two atoms is formed by the sharing of two pairs of electrons, one in a sigma bond and one in a pi bond, with electron density concentrated on two opposite sides of the internuclear axis.
A chemical bond formed between two ions with opposite charges. Ionic bonds form when one atom gives up one or more electrons to another atom. These bonds can form between a pair of atoms or between molecules and are the type of bond found in salts.See more at bond, coordinate bond, covalent bond.. ionic bond-a chemical bond in which one atom loses an electron to form a positive ion and the other atom gains an electron to form a negative ion. electrostatic bond, electrovalent bond. bond, chemical bond-an electrical force linking atoms.