(BIOL 101) Module 1: Lesson 2 - The Chemical Context of Life Vocab List

calcium calcium calcium

consist of protons, neutrons, & electrons

atoms

positively charged; identify the element

protons

neutrally charged; identify the isotope

neutrons

negatively charged; fun? I don’t think so; constantly moving through shells can't stay put

electrons

Which part of the atom is involved in chemical reactions?

electrons

determined by the number of protons; identifies the element

atomic number

isotope

the outermost shell of any atom

valence shell

2 electrons in the first shell 8 electrons in all subsequent shells

octet rule

2 or more atoms bonded together

molecule

2 or more DIFFERENT atoms bonded together

compound

the bond between one atom that gives away its electrons to the more electronegative atom

ionic bond

when two atoms share a pair of valence electrons

covalent bond

the attraction of a given atom for electrons; up to the left on periodic table; flourine is one of the most ____

electronegativity

when the more electronegative atom has one extra electron after attraction gaining a negative charge; a negative ion

anion

when the less electronegative atom has one less electron becoming positively charged a positive ion

cation

compounds with ionic bonds (aka 'salts')

ionic compounds

when the attraction for the electrons by the nuclei in a covalent bond is unequal; electrons will spend more time in the orbital of the more electronegative atom

polar molecule

In a polar bond, the more electronegative atom carries a _____ and the less electronegative atom carries a _____.

partial negative charge; partial positive charge

when the attraction of electrons by the nuclei in a covalent bond is equal/similar in electronegativity; pairs will share fairly

nonpolar molecule

hold many complex molecules together; weak; attracted to electronegative atoms who have no covalent bonds

hydrogen bond