 | Term | Definition |
| |
substance |
has constant properties throughout and a definite composition |
| |
element |
has one kind of atom, found on the periodic table |
| |
compound |
two or more different kinds of atoms bonded in the same ratio |
| |
mixture |
combination of two or more substances, in which each retains its own identity and properties. |
| |
homogeneous |
solution that is even throughout |
| |
heterogeneous |
mixture that is uneven throughout |
| |
suspension |
large particles affected by gravity fall out |
| |
colloid |
midsize particles that do not settle out and appear cloundy |
| |
Tyndall Effect |
scattering of light caused by colloids |
| |
Brownian Motion |
random movement of particles |
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coagulation |
clumping of particles |
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physical property |
can be observed without changing the makeup of the substance |
| |
chemical property |
determines how a substance will react to form other substances |
| |
physical change |
does not change compostistion of a substance |
| |
chemical change |
involves a new substance being formed |
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single displacement |
element + compound = new element + new compound |
| |
double displacement |
compound + compound = new compound + new compound |
| |
synthesis |
element + element = compound |
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decomposition |
compound = element + element |
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combustion |
hydrocarbon + oxygen = CO2 + H2O |
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accuracy |
how close to the "true value" the measurement is |
| |
prescision |
reproducability of the measurement, place value of measuring device increments |
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temperature |
measure of the average kinetic energy of matter |
| |
heat |
the sum of kinetic energy of particles in matter |
| |
energy |
the ability to do work |
| |
specific heat constant |
the amount of heat needed to change the temperature of one gram of a substance by one degree Celsius |
| |
4.184 J/g C |
specific heat of water |
| |
calorimeter |
device used to measure energy changes |
| |
closed system |
system in which heat is not exchanged between matter inside the system and the surroundings |
| |
open system |
heat is exchanged between the system and the surroundings |
| |
groups |
vertical columns on periodic table, indicate valence e- |
| |
periods |
horizontal rows on periodic table, indicate number of energy shells |
| |
metals |
malleable and ductile substances that tend to lose e- and form cations |
| |
nonmetals |
poor conductores of heat and electricity that tend to form anions |
