Chapter 1 Flashcards
molecules:
combination of 2+ elements
chemistry is the science that seeks to understand behavior of matter by studying:
behavior of atoms and molecules
matter:
anything that occupies space and has mass
~can be composed of either atoms or molecules
substances:
specific instance of matter
substances are classified based on:
state and composition
state
solids, liquids, or gases
~solids can be crystalline or amorphous
each atom is one type of:
element
there are only ______ known elements in the universe
118
Only ____ known elements are stable [last long enough to observe and work with]
80
we consider/think of atoms as
indivisible [difficult to break it down or make simpler]
spheres
if a substance is pure, we like to know if it is:
an element or compound
if a substance is a mixture, we like to know if it is:
heterogeneous or homogeneous (same throughout)
physical property
odor, taste, color, appearance, melting/boiling point, density
[chemical does not change when these properties are measured]
chemical property
corrosiveness, flammability, acidity, toxicity, other chemical reactiveness
[chemical does change when these properties are measured]
physical change
alters appearance, but not the chemical structure; relatively easy to reverse
ex) freezing of water; dissolving sugar in water
chemical change
chemical reactions occur when atoms combine in new ways, or re-arrange to form a new chemical
what are the 7 diatomic elements?
hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine, iodine,
H2, N2, O2, F2, Cl2, Br2, I2
Have No Fear Of Ice Cold Beer
“Horses Need Oats For Clear Brown I’s”
solids have a ________ volume and shape
fixed
liquids have a ______ volume and _______ shape
fixed
variable
gases have a ______ volume and shape
variable