6+-+Chemical+Equations+&+Stoichiometry

**Objectives**

6.) Solve stoichiometric problems involving relationships among the number of particles, moles, and masses of reactants and products in a chemical reaction. • Predicting products given known reactants • Classifying chemical reactions as composition, decomposition, single replacement, or double replacement • Determining the empirical or molecular formula for a compound using percent composition data

**Purpose of Unit**

//This unit has 3 segments. Each segment is related to stoichiometry, or the branch of chemistry dealing with quantitative relationships of combining elements (as retrieved from the world wide web at // http://dictionary.reference.com/browse/stoichiometry on 03/13/13).

Segment 1 focuses on balancing equations according to the law of conservation of mass. The student will build skills beginning with counting atoms in a formula, moving to the basics of balancing reactions & naming the parts of the reaction equation. Students will also classify equations as synthesis, decomposition, single displacement, double displacement, & combustion. Lab work focuses on modeling equations.

Segment 2 is the heart of stoichiometry. . . converting particles to moles, moles to particles, moles to grams, grams to moles, grams to particles, and particles to grams. These 6 types of problems are all worked using the factor label method. It is very desirable for each student to have their own scientific calculator in class each day for this segment. Students will refresh their skills in calculations with scientific notation and reporting answers with the correct number of significant digits. Lab work focuses on modeling the mole concept using a variety of beans. A understanding of relative mass is also gained through lab work & is applied to earlier basic knowledge of the atom, its parts, atomic masses, and averages.

Segment 3 deals with the more challenging work of predicting products given a set of known reactants, calculating percent composition, and formulating empirical and molecular formulas. Lab work focuses on calculating percent composition of bubble gum.

**Resources**

mentos demo

media type="file" key="25_energy_chemical_reactions_56100.asx" width="300" height="300"

Mole <--> Gram Video

Calculating Molar Mass Video