Presentation on theme: "Stoichiometry - House Method"— Presentation transcript:
1 Stoichiometry - House Method 1. Start with a balanced chemical equation.Na2CO3 + Ca(OH) NaOH + CaCO3
2 Stochiometry - House Method 2. Place the given information above the proper compounds in the equation; except for moles. Moles will be written below the proper compounds!!120 gX gNa2CO3 + Ca(OH) NaOH + CaCO3
3 Stochiometry - House Method 3. Draw a simple house around each compound used in the problem. Add moles to the downstairs of each house.120 gX gNa2CO3 + Ca(OH) NaOH + CaCO3molemole
4 Stochiometry - House Method 4. Draw arrows to show the path of the conversion from beginning to end.120 gX gNa2CO3 + Ca(OH) NaOH + CaCO3molemole
5 Stochiometry - House Method 5. Set up your factor label conversions in the direction of the arrows.120 gX gNa2CO3 + Ca(OH) NaOH + CaCO3molemole120 g Na2CO3 X 1 mol Na2CO3 X mol NaOH X g NaOH =g Na2CO mol Na2CO mol NaOHNotice that there are no numbers in front of the mol to mol conversion…YET !
6 Stochiometry - House Method 6. The numbers in front of the mol to mol conversion are the addresses (coefficients) of the compounds.120 gX g1Na2CO3 + Ca(OH) NaOH + CaCO31molemole21120 g Na2CO3 X 1 mol Na2CO3 X mol NaOH X g NaOH =g Na2CO mol Na2CO mol NaOH
7 Stochiometry - House Method 7. Solve the math.120 gX gNa2CO3 + Ca(OH) NaOH + CaCO3molemole21120 g Na2CO3 X 1 mol Na2CO3 X mol NaOH X g NaOH =g Na2CO mol Na2CO mol NaOH91 g NaOH
8 Stoichiometry- In Review….. -calc. of quantities in BALANCED chemical equations.
9 Mole Ratio/ Mole Bridge - Must have balanced equation- Use coefficients from balanced equation- Used to get from one substance to anotherSet- Up: # mole of unknown substance#mole of given substance# of moles = Coeff. from balanced equation
10 For Stoichiometry Problems (A Step-by-Step Guide!!!): 1. Balance the equation2. Write given and unknowns with the houses.3. If given is not in moles, convert to moles.4. Do MOLE BRIDGE5. If solving to moles, you're done!!6. If solving to any other unit, do one more conversion tosolve to the proper unit.