Microsoft Word Basic Chemistry Vocabulary List doc

ground state
: The lowest energy state possible for an electron.
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group
: A column (the things up and down) in the periodic table. Elements in 
the same group tend to have the same properties. These are also called 
"families".
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half-life
: The time required for half of the radioactive atoms in a sample to 
decay. When talking about chemical reactions, it's the amount of time 
required to make half the reagent react.
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half-reaction
: The oxidation or reduction part of a redox reaction.
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halogen
: The elements in group 17. They're really reactive.
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heat of reaction
: The amount of heat absorbed or released in a reaction.
Also called the "enthalpy of reaction"
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heat
: The kinetic energy of the particles in a system. The faster the particles 
move, the higher the heat.
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Hess's Law
: The enthalpy change for a change is the same whether it takes 
place in one big step or in many small ones.
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heterogeneous mixture
: A mixture where the substances aren't equally 
distributed. 
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homogeneous mixture
: A mixture that looks really "smooth" because 
everything is mixed up really well.
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Hund's rule
: The most stable arrangement of electrons occurs when they're 
all unpaired.
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hybrid orbital
: An orbital caused by the mixing of s, p, d, and f-orbitals.
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hydration
: When a molecule has water molecules attached to it.
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hydrocarbon
: A molecule containing carbon and hydrogen.
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hydrogen bond
: The tendency of the hydrogen atom stuck to an 
electronegative atom to become attracted to the lone pair electrons on another 

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electronegative atom. It's a pretty strong intermolecular force, which explains 
why water has such a high melting and boiling point.
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