3U+Quantities+in+Chemical+Reactions







__ Activity #1 __ Law of conservation of[| Matter] 1. Summarize the video presentation? How does this relate to the Law of Constant composition? 2.Using the collection of coloured diagrams identify which one represents the Law of conservation of mass? 3. Answer question #1

__ Activity #2 __ Empirical formulas are the whole number molar ratio of elements based on % mass composition in a compound ( in lowest terms ) To determine this: 1) find the mass of each element (assume 100 g and the % becomes mass) 2) Convert to the moles of each element 3) Find the ratio of the elements (take the lowest and divide it into all the others) 4) write the empirical formula with these ratio numbers

The molecular formula is a ratio of the actual number of atoms in the molecule. To find the molecular formula: 1) Take the molecular mass (or molar mass as they are the same number) and see how many times the empirical formula mass fits into the molecular mass u/EFmass = coefficient. 2) Multiply the empirical formula by the coefficient to produce the true molecular formula

Mole challenge [|online quiz] Review unit conversion here

media type="file" key="AA_the mole.swf" width="520" height="520"

[|Stoichiometry 1] [|Stoichiometry quiz]

Review of stoichiometry calculations tutorial media type="file" key="stoichiometry.swf" width="545" height="545"