Presentation on theme: "Moles. The following problems refer to FeSO 4. a.Is the compound ionic or molecular? How do you know? b.Calculate the oxidation state of the iron. c.Write."— Presentation transcript:
The following problems refer to FeSO 4. a.Is the compound ionic or molecular? How do you know? b.Calculate the oxidation state of the iron. c.Write the proper name of the compound. d.Calculate the oxidation state of the sulfur in the SO 4 2- ion. e.Write the reaction that would occur between FeSO 4 and NaCl. f.Calculate how many moles of NaCl are needed to react with 15.4 moles of FeSO 4.
Moles 2 Na+Cl 2 2NaCl 6 moles Na 10 atoms Na ONLY WORKS FOR MOLES, MOLECULES, ATOMS Reaction Stoichiometry
1.How many moles of H 2 and O 2 must react to form 6 moles of H 2 O? 2.How many moles of water must react with 0.25 moles of CaC 2 ? CaC 2 + 2H 2 O C 2 H 2 + Ca(OH) 2
3.How many moles of KCl and O 2 are formed from the decomposition of 6 moles of KClO 3 ? 4.How many grams of oxygen are needed to react with 4.41 g of Li to form Li 2 O? (Ans: 5.08 g)
5.How many grams of oxygen are needed to react with 17.5 g of Al? (Ans: 15.6) Al + O 2 Al 2 O 3 6.How many grams of oxygen will react with 25.0 g of C 2 H 6 ? (Ans: 93.3 g) C 2 H 6 + O 2 CO 2 + H 2 O
7.How many grams of P 4 and O 2 are needed to make 3.62 g of P 2 O 5 ? (Ans: 1.58 g, 2.04 g) P 4 + O 2 P 2 O 5
Calculate the mass of aluminum required to produce g of iron. Also calculate the formula units of Fe 2 O 3 that are used in the process. Al + Fe 2 O 3 Al 2 O 3 + Fe 363 g Al, 4.05 X 10 24
What mass of oxygen is needed to react with 16.7 g of iron to form Iron(III)oxide? How many molecules of O 2 are used? 4Fe + 3O 2 2Fe 2 O 3 Ans: 7.18 g, 1.35 X atoms
Lead(II)Nitrate reacts with potassium iodide to form potassium nitrate and lead(II)iodide. a.Write the balanced reaction b.What type of reaction is this? c.Calculate the grams of potassium nitrate formed from the reaction of 18.0 g of lead(II)nitrate. d.Calculate atoms of iodine in the lead(II) iodide
Moles 1.Sandwich analogy: 14 slices of bread 4 pieces of turkey (low fat) Maximum # of sandwiches? 2. Limiting Reactant – Totally consumed in a reaction. No leftovers Limiting Reactant
1.How many grams of H 2 SO 4 can be formed from the rxn of 5.00 moles of SO 3 and 2.00 moles of H 2 O? SO 3 + H 2 O H 2 SO 4 (Ans: 196 g)
2. How many grams of H 2 O can be formed from the rxn of 6.00 moles of H 2 and 4.00 moles of O 2 ? O 2 + H 2 H 2 O
3. How many grams of NaCl can be formed from the reaction of mol of Na and mol of Cl 2 ? (Ans: 11.7 g) 2Na + Cl 2 2NaCl
4. How many grams of Ag can be formed from the rxn of 2.00 g of Zn and 2.50 g of silver nitrate? How much excess reactant remains? Zn + AgNO 3 Ag + Zn(NO 3 ) 2 (Ans: 1.59 g Ag, 1.52 g xs zinc)
5. How many grams of Ag 2 S can be formed from the rxn of 15.6 g of Ag and 2.97 g of H 2 S? (Assume O 2 is in excess) 4Ag + 2H 2 S + O 2 2Ag 2 S + 2H 2 O (Ans: 18.0 g)
6. How many grams of CO 2 can be formed from the rxn of 40.0 g of CH 3 OH and 46.0 g of O 2 ? 2CH 3 OH + 3O 2 2CO 2 + 4H 2 O (Ans: 42.2 g)
7.How many grams of Ba 3 (PO 4 ) 2 can be formed from the rxn of 3.50 g of Na 3 PO 4 and 6.40 g of Ba(NO 3 ) 2 ? (Ans: 4.92 g) Na 3 PO 4 + Ba(NO 3 ) 2 Ba 3 (PO 4 ) 2 + NaNO 3
Moles A.Formula: Actual Yield X 100 = % Yield Theoretical Yield Percent Yield
1.What is the % yield if you start with grams of C and obtain 1.49 g of H 2 gas? C + H 2 O CO + H 2 (Ans: 89.2%)
2.Carbon was heated strongly in sulfur(S 8 ) to form carbon disulfide. What is the percent yield if you start with g of sulfur and collect 12.5 g of CS 2 ? 4C + S 8 4CS 2 (Ans: 78.0%)
3.An aluminum ladder oxidizes according the following unbalanced equation: Al + O 2 Al 2 O 3 a grams of aluminum reacted with excess oxygen. Calculate the theoretical yield. (189 g) b.If the percent yield was 67.4%, calculate the actual yield. (127 g) c.Calculate how many grams of oxygen were used. (88.9 g) d.Identify the type of reaction that occurred.
11.5 grams of sodium reacts with 15.0 grams of chlorine (Cl 2 ) to form sodium chloride grams of NaCl are collected. a.Write the balanced chemical equation. b.Identify the limiting reactant. c.Calculate the theoretical yield of NaCl. (24.7g) d.Calculate the percent yield. (73.7%) e.If the percent yield for a different trial (starting with same amounts) was only 60.4%, calculate the actual yield. f.Identify the type of reaction that occurred.
Moles 1.Molarity = measure of the concentration of a solution 2.Molarity = moles/liter Similar to Density = g/L Molarity
Moles 3.Which is more concentrated? 1 M HCl3 M HCl Molarity
Moles 1.What is the molarity of a soln that contains g of H 2 SO 4 in enough water to make mL of soln? (Ans: 2.00 M) 2.What is the molarity of a soln made by dissolving 23.4 g of Na 2 SO 4 in enough water to make 125 mL of soln? (Ans: 1.32 M) Molarity
Moles 3.What mass of HCl is present in 155 mL of M HCl? (Ans: 3.06 g) 4.How many grams of NaOH are in 5.00 mL of M NaOH? (Ans: g) Molarity
Moles 5.What volume of M NaOH is needed to provide moles? (Ans: 6.44 mL) 6.What volume of M HCl is needed to provide g of HCl?(Ans: 25 mL) Molarity
Moles 1.Mixing from a solid 2.How would you prepare mL of M Na 2 SO 4 ? Mixing From a Solid
3.Write directions for the preparation of mL of M KMnO 4 (10.5g) 4. Write directions for the preparation of mL of M NaOH (0.02 g) Mixing From a Solid
Moles 1.Dilution Formula: M 1 V 1 = M 2 V 2 2. Used when you are starting with a more concentrated soln. (Grape juice concentrate, Coke syrup) Diluting from a Solution
Moles 3.What is the molarity of a soln of KCl that is prepared by diluting 855 mL of M soln to a volume of 1.25 L? (Ans: M) 4.You have a 3.00 L bottle of 11.3 M HCl. What volume of it must be diluted to make 1.00 L of M HCl? (Ans: 49.1 mL) Diluting from a Solution
Moles The following questions refer to a M solution of NaNO 3. a.Calculate how many grams of NaNO 3 are present in 50.0 mL of the solution. (0.419 g) b.Calculate the volume of the solution required to provide grams of NaNO 3. (22.4 mL) c.State how you would prepare mL of the solution starting with solid NaNO 3. (4.19 g) d.State how you would prepare mL of the solution starting with a large 3-L bottle of 2.00 M NaNO 3 (aq) (24.7 mL)
c.1) Mass 4.19 g of NaNO 3 2) Place in a small volume of water to dissolve 3) Dilute to 500 mL d.1) Measure 24.7 mL of M NaNO 3 2) Dilute to 500 mL
Moles The following questions refer to this equation: H 2 SO 4 + NaOH H 2 O + Na 2 SO 4 a.Calculate how many moles of NaOH are present in 25.0 mL of M NaOH. b.Calculate how many grams of Na 2 SO 4 are produced if the 25.0 mL of M NaOH reacts. c.Calculate the moles of H 2 SO 4 that would be required. d.Calculate the volume of H 2 SO 4 required if the concentration is M. e.State what type of reaction occurred.
The following questions refer to the following unbalanced reaction of ethanol (C 2 H 5 OH ) C 2 H 5 OH + O 2 CO 2 + H 2 O a.State what type of reaction is occurring. b.Calculate the grams of oxygen needed to react with grams of ethanol. c.Calculate the number of CO 2 molecules produced. d.The density of ethanol g/cm 3. Calculate the volume of ethanol needed to provide grams.
Moles 5.a) 10.0 molb) 1.67 mol 7.a) 21.9 gb) 29.3 gc) 6.60 g 11a) 83.6 gb) 5.74 molc) 279 g d) ge) 175 g g Fe, 4.05 X Fe 2 O g Cu g Cl 2 23.a) 1.60 molb) 1.50 molc) 2.81 mol d) 1.90 mol g g CO 2, 10.4 g HCl
Moles % g g g L M L mL
Moles Sodium bicarbonate (NaHCO 3 ) was decomposed to compare the actual mass of sodium carbonate (Na 2 CO 3 ) to the theoretical mass. About two grams of NaHCO 3 was placed in a petri dish. The dish was heated on a hotplate, allowed to cool, and then massed. The theoretical mass of Na 2 CO 3 was calculated from the chemical equation and compared to the actual mass. This experiment was accurate, with a percent error of 5.3%. The experiment was not precise because it produced a range of 0.80 grams in the actual mass of Na 2 CO 3.
Lab Notes Goggles Use aluminum pans instead of petri dishes 4 trials total – Mark your dishes Wash dishes out at end and leave all materials at station BE CLEANER ABOUT THE BALANCE!!!!! Ignore back of sheet, use AP lab report format All work must be unique