PTOE and Bohr/Lewis Diagrams Flashcards
what type of change is this?
•chemical substance and formula remain the same
•molecules stay intact
•changes in state of matter
•small energy change
physical
what type of change is this?
•chemical substances and formulas change
•bonds broken and formed
•new substances made
•medium energy change
chemical
what is matter?
anything that has mass and occupies space
what are characteristics of solids? (3)
•both definite shape and volume
•forces between atoms are strong
•molecular motions are slow
what are characteristics of liquids? (5)
•definte volume
•indefinite shape
•slightly compressible
•forces between atoms are weaker
•molecular motions are more rapid
what are characteristics of gases? (4)
• indefinite shape and volume
•readily compressible and capable of infinite expansion
•forces between atoms are very weak
•molecular motions are very rapid
what defines pure substances?
constant composition
what defines mixtures?
variable composition
what defines compounds?
combination of elements
(decomposed by heat/electricity)
what defines elements?
not decomposed by heat or electricity
what defines homogenus mixtures?
same properties throughout
what defines heterogenus mixtures?
different properties in small amounts
properties of alkali metals: (3)
• soft, shiny, silver metals
•react violently with water
•most reactive metals
properties of alkali earth metals: (2)
•shiny, silver, but not as soft
•form oxide coatings in air
properties of halogens: (1)
•extremely reactive nonmetals
