CH 3 Mass Relations in Chemistry; Stoichiometry. Atomic Mass. Indicates how heavy an element is compared to another element. Units AMU---Atomic Mass Unit Defined as 1/12 of the mass of a C-12 atom. Atomic Mass from isotope composition. Isotopic Abundance: the natural of an isotope.
Reacquaint yourself with the mole wheel.
Use part / whole, assume you have 1 mole of compound. (the math is easier)
1mol = K2CrO4194.20 g
%K = 78.90/194.20 =
Use the following K= 26.6%, Cr= 35.4%, O = 38.0%
An organic sample containing only C, H, O atoms weighs 1.000g
Burning the sample gives 1.466g CO2,
Find the simplest formula…
Usually 1 is in excess; some left when reaction is over.
1 is limiting; completely consumed to give the theoretical yield of product.
Actual/Theoretical (x100) = % Yield