Chapter 2 Flashcards
_____ and ____ bond together to form compound
Elements and atoms
Compound
mixture of two or more different atoms at a fixed ratio
Electrons
smaller then protons, negative charge
Another word for weight
dalton
Atomic number
of protons
Valence shell
deals with the activity, loves to have a full shell, the outer most shell
Valency
of electrons needed to fill outer shell
Covalent bond
two atoms share one or more outer shell electrons. strongest bond
Molecule
two or more atoms held together by a covalent bond
Electronegativity
the attraction for shared electrons
Polar covalent bonds
unequal sharing
Non polar covalent bonds
equal sharing
Ionic bond
attraction that holds molecules together. donates e-, accepts e-
Cation
positive charge. donated e-
Anion
negative charge. accepted e-
Salt
almost always exist in nature as crystals. tough strong dry bond. ions interact w/ water and break up
Crystal line state
strong expose to water
Hydrogen bonds
weak bonds, but essential to life
Cohesion
tendency of molecules of the same kind to bind together
Adhesion
tendency of to bind together
Surface tension
a measure of how difficult it is to break the surface of a liquid
Heat capacity
how fast a liquid will warm up or cool down
Heat
form of energy associated with movement of molecules
Temperature
measures the intensity of heat
Evaporative cooling
when a substance evaporated the surface of the liquid that remains behind cools down
Solution
liquid consisting of a uniform mixture of two or more substances
Aqueous solution
one in which water is the solvent
Ex of aqueous solution
cells in our bodies
Acid
compound that releases hydrogen to a sol’n
Base
compound that accepts hydrogen and removes them from sol’n
Between each pH level it goes down by units of..
10
Buffer
substance that minimizes changes in pH. accepts H when excess and donates H when depleted
pH of blood
7.4
pH
measures hydrogen in a sol’n
