BIO 110 Lecture Notes - Lecture 1: Cardiology, Chemical Polarity, Atomic Number
Document Summary
Chemical bonding and molecules: chemical reactions enable atoms to give up or acquire electrons, completing their outer shells, chemical reactions usually result in atoms, staying close together, being held together by attractions called chemical bonds. Ionic bonds: when an atom loses or gains electrons it becomes electrically charged, ions: charged ions, ionic bond: formed between oppositely charged ions because opposite charges attract each other. Polar covalent molecule: water is a compound in which the electrons in its covalent bonds are not shared equally, this causes water to be a polar molecule, one with an uneven distribution of charge. Hydrogen bonds: polarity of water results in weak electrical attractions between neighboring water molecules, these wear attractions are called hydrogen bonds. Chemical reactions: cells constantly rearrange molecules by breaking existing chemical bonds and forming new ones, chemical reactions: changes in the chemical composition of matter, ex. Reaction between oxygen gas and hydrogen gas forms water.
