Microsoft Word Basic Chemistry Vocabulary List doc

spectator ions
: The ions in a reaction that don't react.
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spontaneous change
: A change that occurs by itself. All exothermic 
reactions are spontaneous. However, this doesn't mean that all exothermic 
reactions are fast. The combustion of gasoline is spontaneous, but not very 
fast unless you add a little energy. 
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standard temperature and pressure
: One atmosphere and 273 K.
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steric hindrance
: This is the idea that the functional groups on big molecules 
get in the way of a chemical reaction, making it go slower. Imagine a fat guy 
trying to get into a Honda Prelude - that's steric hindrance.
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stoichiometry
: The art of figuring how much stuff you'll make in a chemical 
reaction from the amount of each reagent you start with.
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STP
: See standard temperature and pressure.
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strong acid
: An acid that fully dissociates in water
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strong nuclear force
: The force that holds the nucleus together. As the 
name suggests, this force is strong.
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structural formula
: See Lewis structure.
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sublimation
: When a solid can change directly into a gas. Dry ice does this.
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supercooling
: When you cool something below its normal freezing point
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supersaturated
: When more solute is dissolved in a liquid than is 
theoretically possible. This doesn't happen much, as you might imagine.
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surface tension
: A measurement of how much the molecules on a liquid tend 
to like to stick to each other. If something has a high surface tension, it likes to 
bead up. 
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suspension
: A mixture that looks homogeneous when you stir it, but where 
the solids settle out when you stop. Mud is a very short-lived suspension, 
while peanut butter is a very long-lived suspension.

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