1. Stoichiometry: mol-to-mol ratios
calculations of quantities in chemical rxns
–how much reactant is needed or
–how much product is formed
Balanced chemical equations show the amount of:
atoms, molecules, moles, and mass
Most important are the ratios of reactants and products in moles, or…
mol-to-mol ratios

2. Atoms

3. Molecules

4. Moles

5. Mass

6. Mass and atoms are conserved in every chemical reaction
Mass & Atoms
Mass and atoms are conserved in every chemical reaction

7. Atoms Mass Molecules Moles 2 H2S(g) + 3 O2(g)  2 SO2(g) + 2 H2O(g)
Interpret this equation in terms of:
Atoms
Mass
Molecules
Moles 12 12 g g 5 4 5 4

8. 3 W + F + H + 2 P + S → TRIKE Quick Quiz!
A manufacturer of tricycles has 15 wheels(W), 6 frames(F), 5 handlebars(H), 12 seats(S), and 8 pedals(P). How many tricycles can be manufactured using these parts?
5 tricycles
3 tricycles
6 tricycles
4 tricycles
3 W + F + H + 2 P + S → TRIKE

9. Quick Quiz.
2. What is the most important information from a chemical equation?
states of matter
moles of products
mole ratios of reactants & products
masses of reactants and products