Vocabulary Chemistry

 VOCABULARY IN CHEMISTRY

NO	VOCABULARY
1	Solution : A homogeneous mixture is where a substance called a solute is completely dissolved into another substance called a solvent. For example, a solution is formed when a salt dissolves in water to make a brine solution.
2	Buffer :  A liquid that resists change in pH by  the addition of acid or base.  It consists of a weak acid and it's  conjugate base (acetic acid and sodium acetate, for example).
3	Polymer : A molecule containing many repeating units.  Plastics are polymers and are formed by free radical chain reactions.
4	Radioactive :  When a substance has an unstabl e nucleus that can fall apart, it's referred to as radioactive.
5	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.
6	Oxidation : The name for the process when oxygen combines with other elements to form compounds.
7	Molality :  The number of moles of solute per  kilogram of solvent in a solution.  This is a unit of concentration that 's not anywhere near as handy or common as molarity.
8	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".
9	Heterogeneous mixture :  A mixture where the substances aren't equally distributed.
10	Homogeneous mixture :  A mixture that loo ks really "smooth" because everything is mixed up really well.
11	Orbital :  This is where the electrons in an atom live.
12	Equilibrium :  When the forward rate of a chem ical reaction is the same as the reverse rate.  This only takes place in reversible reactions because these are the only type of reaction in which the  forward and backward reactions can both take place
13	Calorimeter : Tool used for measuring heat with calorimetry method.
14	Salt : Salt is a chemical compound formed by the reaction of acids and bases.
15	Complex ion :  An ion in which a central atom (usually a transition metal) is surrounded by a bunch of molecules like water or ammonia (called "ligands")
16	Concentration :  A measurement of t he amount of stuff (sol ute) dissolved in a liquid (solvent).  The most common concent ration unit is molarity (M), which is equal to the number of moles of solute divided by the num ber of liters of solution.
17	The PH : pH scale measures the activity of hydrogen ions in a substance. If a substance has a pH less than 7 is said to be acidic. If the pH is greater than 7 then it is said to be alkaline or alkali.
18	Redox reaction :  A reaction that has bot h an oxidation and reduction
19	Oxidation number :  The apparent charge on an atom
20	Coagulation : The process of formation of clots due to the addition of certain substances and the clot settles.
21	Alcohol :  An organic molecule containing an -OH group
22	Neutralization reaction :  The reaction of an acid with a base to form water and a salt.
23	Adsorption :  When one substance collects of the surface of another one
24	Alloy :  A mixture of two metals.  Usual ly, you add very sm all amounts of a different element to make  the metal stronger and harder.
25	Molecular compound :  A compound held together by covalent bonds.
26	Node :  A location in an orbital where  there's no probability of finding an electron.
27	Phase :  The state of a compound (solid, liquid, or gas)
28	Colloid : A mixture that is midway between homogeneous and heterogeneous mixtures
29	Insoluble :  When something doesn't dissolve.
30	Nuclear reaction :   Any reaction that involves a change in the nucleus of an atom.  Nuclear reactions take loads  of energy, which is why you don't see them much around the lab.
31	Catalyst :  A substance that speeds up a chemical reaction without being used up by the reaction. Enzymes are cata lysts because they allow the reactions that take place in the body to occur fast enough that we can live
32	Addition : One type reactions of carbon compounds wherein the double bond is saturated
33	Adhesion : The force of attraction between different molecules.
34	Alkenes : Aliphatic hydrocarbons with one carbon-carbon double bond
35	Alkyne : Aliphatic hydrocarbons with one carbon-carbon triple.
36	Chemical equation :  The recipe that describes what you need to do to make a reaction take place.
37	Energy level :  A possible level of energy that  an electron can have in an atom.
38	Physical property:   A property which can be determined without changing something chemically.  If that doesn't make sense, see the definition of "chemical change".
39	Binary compound :  A compound only having two elements
40	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).