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Chem3 Ch8.p1
define
Term | Answer |
---|---|
mole | the number of carbons in exactly 12 grams of pure Carbon-12 |
Avogadro's Number | 1 mol = 6.022 x 10 to the power 23 (6.022 x 10 to the 23 atoms/mole) |
Molar Mass | is the mass in grams of 1 mole of atoms. The mass of one mole of atoms(g/mol): 1 mole of Si weighs 28.09 g 0r 28.09 amu |
Atomic Mass | is the average atomic mass of isotopes of an element expressed in atomic mass units (amu). the atomic mass is listed in the periodic table just below the element symbol. 1 average Si atom is 28.09 amu |
Molar Mass of a compound | is the sum of the molar masses in the compound in grams per mole (g/mol) |
Percent Composition | Mass percent of each element in a compound |
Empirical Formulas | Simplest formulas show which elements are present in a compound , with their mole ratios indicated as subscripts. Subscripts are mole-to-mole ratios (P2O5=2 mole P:5 mole O) |
Molecular Formulas | Chemical formulas indicate the type and number of atoms in a molecule. Subscripts are actual numbers of atoms per molecule (P4O10= 4 mole and 10 mole O). Multiply empirical subscripts by n to get molecular subscripts |