Kimistry+Chemistry+Vocabulary

=Kimistry Chemistry Vocabulary=


 * **__absolute temperature__**: This is a temperature reading made relative to absolute zero. We use the unit of Kelvins for these readings.
 * **__absolute zero__**: This is the lowest temperature possible. If you remember that temperature is a measurement of how much atoms move around in a solid, you can guess that they stop moving entirely at absolute zero. In reality, bonds still vibrate a little bit, but for the most part you don't see much happening.
 * **__accuracy__**: When you measure something, the accuracy is how close your measured value is to the real value. For example, if you're actually six feet tall and your brother measures your height as six feet, one inch, he's pretty accurate. However, if your cousin measures your height as twelve feet, 13 inches, he's not accurate at all.
 * **__acid__**: This is anything that gives off H+ ions in water. Acids have a pH less than 7 and are good at dissolving metals. They turn litmus paper red and phenolphthalein colorless.
 * **__acid anhydride__**: This is an oxide that forms an acid when you stick it in water. An example is SO3 - when you add water it turns into sulfuric acid, H2SO4.
 * **__acid dissociation constant (Ka)__**: This is equal to the ratio of the concentrations of an acid's conjugate base and the acid present when a weak acid dissociates in water. That is, if you have a solution of Acid X where the concentration of the conjugate base is 0.5 M and the concentration of the acid is 10 M, the acid dissociation constant is 0.5/10 = 0.05.
 * **__activated complex__**: In a chemical reaction, the reagents have to join together into a great big blob before they can fall back apart into the products. This great big blob is called the activated complex (a.k.a. transition state)
 * **__activation energy__**: The minimum amount of energy needed for a chemical reaction to take place. For some reactions this is very small (it only takes a spark to make gasoline burn). For others, it's very high (when you burn magnesium, you need to hold it over a Bunsen burner for a minute or so).
 * **__activity series__**: This is when you arrange elements in the order of how much they tend to react with water and acids.
 * **__actual yield__**: When you do a chemical reaction, this is the amount of chemical that you actually make (i.e. The amount of stuff you can weigh).
 * **__addition reaction__**: A reaction where atoms add to a carbon-carbon multiple bond.
 * **__adsorption__**: When one substance collects of the surface of another one.
 * **__alcohol__**: An organic molecule containing an -OH group
 * **__aldehyde__**: An organic molecule containing a -COH group
 * **__alkali metals__**: Group I in the periodic table.
 * **__alkaline earth metals__**: Group II in the periodic table.
 * **__alkane__**: An organic molecule which contains only single carbon-carbon bonds.
 * **__alkene__**: An organic molecule containing at least one C=C bond
 * **__alkyne__**: An organic molecule containing at least one C-C triple bond.
 * **__allotropes__**: When you have different forms of an element in the same state. The relationship that white phosphorus and red phosphorus have to each other is that they're allotropes.
 * **__alloy__**: A mixture of two metals. Usually, you add very small amounts of a different element to make the metal stronger and harder.
 * **__alpha particle__**: A radioactive particle equivalent to a helium nucleus (2 protons, 2 neutrons)
 * **__amine__**: An organic molecule which consists of an ammonia molecule where one or more of the hydrogen atoms has been replaced by organic groups.
 * **__amino acid__**: The basic building blocks of proteins. They're called "amino acids" because they're both amines (they contain nitrogen) and acids (