21 dozen eggs = 12 eggs1 Gross pencils = 144 pencils1 Ream of paper = 500 sheets of paper
3The Mole 1 mole = 6.022 x 1023 things Avogadro’s number The number of carbon atoms in 12g of C-12Abbreviation: “mol”How much does this weigh?
41 mole C atoms = 6.022 x 1023 Carbon atoms 6.022 x 1023 Carbon atoms = 1 mole of carbon atoms1 mole bicycles = x 1023 bicycles6.022 x 1023 bicycles = 1 mole of bicycles1 mole of anything = x 1023 items of anything6.022 x 1023 items of anything = 1 mole of anything
6Molar Mass The mass, in grams, of one mole of any element or compound Abbreviated with capital, italicized MUnit = grams/mole = g/molAlso called Formula Mass and Formula Weight
7ProblemsYou need mol Cu for an experiment, how many grams should you use? How many atoms of Cu is this?You have g Hg. How many moles are present? If Hg has a density of g/mL, what volume do you have?
8Write the molecular formula or formula unit for the compounds above. Cl-Na+Cl-Na+Cl-Write the molecular formula or formula unit for the compounds above.What are the molecular and formula weights for the compounds above?What is the mass of 1.34 mole of the first compound? What is the mass of carbon in this sample?Na+Cl-Na+How many moles of Sodium Chloride are present in 9.29 g? How many moles of sodium are present in the sample?How many oxygen atoms are there in 5.62g of Carbon Dioxide?
9Your nurse gives you 10. 0g morphine, C17H19NO3 , for pain Your nurse gives you 10.0g morphine, C17H19NO3 , for pain. How many moles is this? How many grams of oxygen are present in this dose of analgesic?
11Law of Conservation of Matter/Mass Matter is neither created, nor destroyed, but is merely rearrangedThe mass of the reactants must equal the mass of the productsH2 (g) + Cl2(g) 2 HCl (g)
12Balancing Chemical Equations Zn(s) + HCl(aq) H2(g) + ZnCl2(aq)Write the unbalanced equationBalance the atoms of one elementChoose another element and balance itContinue until all elements have the same number of atoms on both sides of the equationCheck yourself
17Single replacement/displacement: one element reacts with a compound to form a new compound and release a new element2 Na + 2 H2O 2 NaOH + H2
18Exchange or Double replacement/displacement: an interchange of partners between two compounds Pb(NO3)2(aq) + K2CrO4(aq) PbCrO4(s) + 2 KNO3(aq)
19Combustion rxns: the burning of a compound, usually a hydrocarbon, in oxygen to form heat, carbon dioxide and water
20ProblemsBalance the following equations and identify the type of reaction present.__C3H8(g) + __O2(g) __CO2(g) + __H2O(g)__BaCl2(aq) + __Na2SO4(aq) __BaSO4(s) + __NaCl(aq)__Fe(s) + __H2O(l) __Fe3O4(s) + __H2(g)__Pt(s) + __F2(g) __PtF4(l)__H3BO3(s) __B2O3(s) + __H2O(l)__C4H10(g) + __O2(g) __CO2(g) + __H2O(g)
21Stoichiometry Problems If you have 10.0g C4H10 (butane), how many grams of water can you make upon combustion?How much O2 do you need in problem 1 if you’d like to produce 7.39g CO2?How much CO2 is produced upon combustion of 4.3g of propane (C3H8)?
22__C6H12O6(s) + __O2(g) __CO2(g) + __H2O(l) Using the equation below, calculate the amount of glucose you started with if you produced 12.76g CO2?How much glucose was consumed in order to produce mL of H2O?__C6H12O6(s) + __O2(g) __CO2(g) + __H2O(l)
23Jim Bob got a job at a chair factory Jim Bob got a job at a chair factory. His boss tells him that he’s going to lunch and when he comes back, Jim Bob better have 5 chairs made or he’s fired. JB gets to work. He counts 32 arms, 18 legs, 4 backs, and 2 seats. Will JB get fired?
24Limiting ReagentLimiting Reagent/Reactant/Factor: the reactant/factor that determines the amount of product formedOther reactants are “in excess”Cheaper reactants are usually in excess
25ProblemsYou have 10.0 moles H2 and 1.00 mol O2. How much H2O can you make?You combust 10.2 mol propane in 7.80 mol O2. How much CO2 can you produce?
26If 2. 3 mol carbon disulfide reacts with 5 If 2.3 mol carbon disulfide reacts with 5.4 mol oxygen to form carbon dioxide and sulfur dioxide, what mass of sulfur dioxide is formed?5.50 g silicon dioxide reacts with 4.71g Carbon to from silicon carbide and carbon monoxide. What mass of carbon monoxide is formed?
27Percent YieldTheoretical Yield: the maximum possible quantity of product100% yieldActual/Experimental Yield: quantity of product actually obtainedPercent Yield: efficiency of reactionPY = (actual yield/theoretical yield) x 100
28ProblemsFrom the previous question, the theoretical yield of CO is 5.13 g. If you obtained 4.32g CO, what was your % yield?You react 4.41 mol carbon monoxide with 8.39 mol hydrogen gas to get 122g methanol. What is your percent yield?