Apply the concept of percent yield to stoichiometric problems. Methanol can be produced through the reaction of CO and H 2 in the presence of a

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1 Apply the concept of percent yield to stoichiometric problems. Methanol can be produced through the reaction of CO and H 2 in the presence of a catalyst. CO (g) + H 2 (g) CH 3 OH (l) If 75.0 g of CO reacts to produce 68.4 g CH 3 OH, what is the percentage yield of CH 3 OH?

2 Aluminum reacts with excess copper (II) sulfate according to the reaction given below. If 1.85 g of Al react and the percentage yield of Cu is 56.6%, what mass of Cu is produced? Al (s) + CuSO 4 (aq) Al 2 (SO 4 ) 3 (aq) + Cu (s)

3 Level 5: Apply the concept of limiting reactants to novel situations. I combined 34 grams of copper (II) chloride and 27 grams of sodium hydroxide. If I determined that my percent yield for the reaction was a paltry 82%, what mass of copper (II) hydroxide did I produce?

4 Chapter 11 Section 3 Gas Volumes and the Ideal Gas Law Molar Volume of a Gas Recall that one mole of a substance contains a number of particles equal to Avogadro s constant ( ). example: one mole of oxygen, O 2, contains diatomic molecules. In addition, one mole of any gas will occupy the same volume as one mole of any other gas at the same conditions, despite mass differences. The volume occupied by one mole of gas at STP is known as the standard molar volume of a gas, which is L (rounded to 22.4 L).

5 The Mole Rule Example 1 mole = xx g 1 mole He or 4.00 g 4.00 g 1 mole He 1 mole = x atoms 1 mole or 6.022x x mole 1 mole = 22.4 Liters of gas (at STP) 1 mole or 22.4 L 22.4 L 1 mole STP = 0 C or K and 1 atm

6 Chapter 11 Section 3 Gas Volumes and the Ideal Gas Law Volume to Moles Knowing the volume of a gas, you can use the conversion factor 1 mol/22.4 L to find the moles (and therefore also mass) of a given volume of gas at STP. Example: How many moles of gas are in 5.00 L at STP? 1 mol 5.00 L of gas mol of gas 22.4 L Volume to Moles problem

7 Chapter 11 Section 3 Gas Volumes and the Ideal Gas Law Mole to Volume You can also use the molar volume of a gas to find the volume, at STP, of a known number of moles or a known mass of gas. example: What volume does mol of gas occupy at STP? 22.4 L mol of gas 17.2 L of gas 1 mol Moles to volume problem

8 What volume does mol of gas occupy at STP? Mole to volume Converting to volume so use mol of gas 22.4 L 1 mol 1.53 L of gas

9 What quantity of gas, in moles, is contained in 2.21 L at STP? Volume to moles Converting to moles so use 2.21 L of gas 1 mol L mol of gas

10 Propane, C 3 H 8, is a gas that is sometimes used as a fuel for cooking and heating. The complete combustion of propane occurs according to the following balanced equation. C 3 H 8 (g) + 5O 2 (g) 3CO 2 (g) + 4H 2 O(g) (a) What will be the volume, in liters, of oxygen required for the complete combustion of L of propane? L C H L O L C 2 H L O 2

11 Propane, C 3 H 8, is a gas that is sometimes used as a fuel for cooking and heating. The complete combustion of propane occurs according to the following balanced equation. C 3 H 8 (g) + 5O 2 (g) 3CO 2 (g) + 4H 2 O(g) (b) What will be the volume of carbon dioxide produced in the reaction? Assume that all volume measurements are made at the same temperature and pressure L C H L CO 1 L C H L CO 2

12 Nitrogen monoxide reacts with oxygen according to the equation below: 2NO(g) + O 2 (g) ---> NO 2 (g) How many liters of NO (reacting with excess oxygen) are required to produce 3.0 liters of NO 2?

13 0.082

14 At what temperature will moles of neon gas occupy liters at 1.95 atmospheres? PV = nrt (R = 0.082)