Mole/Stoichiometry Vocab

Mole = the amount of a substance that contains as many particles as 12 grams of carbon-12.  6.022 to the 23rd.

Molar Mass = the mass of one mole of a pure substance (unit g/mol)

Percent composition = the percent by mass of each element in a compound

Emprical Formula = the symbols for the elements combined in a compound with subscripts showing the smallest whole ratio.

Molecular Formula = a chemical compound whose simplest units are molecules, formula that describes the exact composition of the molecule

Mole ratio = a conversion factor that relates the amounts of a substance in moles to any other substance involved in a chemical reaction

No vocab Tuesday (semester exam preparation)

Limiting reacant/reagent = the reactant that limits the amount of other reacants used forming a limiting amount of products produced.

Excess reacant/reagent = The reactant that has leftover (unused) amounts after the reaction is complete.

Theorectical Yield = this is a value obtained by completing a mass to mass problem that begins with a stated amount and by virtue of math gives a value of mass that could be produced if carried out under ideal situations.

Actual yield = this is a value that is obtained by physically carrying out the reaction and obtaining an experimental value.

Percent Yield = this compares theoretical yield and actual yield as a percent.  Actual divided by theoretical x 100 = percent yield.

Stoichiometry = it is the accounting, or math, behind chemistry. Given enough information, one can use stoichiometry to calculate masses, moles, and percents.

catalyst = a chemical substance placed into a reaction to speed up the time it takes for the reaction to occur.  It is not consumed in the reaction.

Chemical reaction=a change in which one or more substances are changed into one or more new substances.

hydrate = a compound in which the ions are attached to one or more water molecules.

formula mass = same calculation as molar mass

enthalpy of reaction =  the change in enthaply (heat) accompanying a chemical reaction.

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