2. For the following reaction, calculate how many moles of each product are formed when 0.356 moles of PbS completely react. Assume there is an excess of oxygen.
3. For the following reaction, calculate how many grams of each product are formed when 4.05 g of water is used.
5. Determine the percent yield of the following reaction when 2.80 g of P reacts with excess oxygen. The actual yield of this reaction is determined to by 3.89 g of P2O5.
Properties of Liquids and Solids
Instructions: Answer the following questions using the following information: ∆Hfus=6.02 kJ/mol; ∆Hvap= 40.7 kJ/mol; specific heat of water is 4.184 J/g∙˚C; specific heat of ice is 2.06 J/g∙˚C; specific heat of water vapor is 2.03 J/g∙˚C.
1. How much heat is required to vaporize 25 g of water at 100˚C?
2. How much heat is required to convert 25 g of ice at -4.0 ˚C to water vapor at 105 ˚C (report your answer to three significant figures)?
3. An ice cube at 0.00 ˚C with a mass of 8.32 g is placed into 55 g of water, initially at 25 ˚C. If no heat is lost to the surroundings, what is the final temperature of the entire water sample after all the ice is melted (report your answer to three significant figures)?
Mixtures and Solutions
Instructions: Use the following image to answer the following questions.
1. A solution contains 40 g of NaCl per 100 g of water at 100˚C. Is the solution unsaturated, saturated or supersaturated?
2. A solution contains 50 g of KCl per 100 g of water at 25˚C. Is the solution unsaturated, saturated or supersaturated?
Solubility Graph [Online Image]. Retrieved November 12, 2018 from https://socratic.org/chemistry/solutions-and-their-behavior/solubility-graphs
3. A solution contains 10 g of KNO3 per 100 g of water at 30˚C. Is the solution unsaturated, saturated or supersaturated?
4. An 8 oz bottle of Dr. Pepper made with imperial cane sugar (C12H22O11) contains 27 g of sugar in 236.6 mL of water. What is the molarity of the solution with respect to cane sugar?
5. Calculate the mass of NaCl in a 55 mL sample of a 3.5 M saline solution.
6. What volume of water should be added to 2.6 g of KCl to make a 4 M solution?
Acid/Base: The Water Constant and pH
Instructions: Determine if each solution is acidic, basic, or neutral.
1. [H3O+] = 1 x 10-10 M; [OH-] = 1 x 10-4 M
2. [H3O+] = 1 x 10-7 M; [OH-] = 1 x 10-7 M
3. [H3O+] = 1 x 10-1 M; [OH-] = 1 x 10-13 M
4. [H3O+] = 1 x 10-13 M; [OH-] = 1 x 10-1 M
Instructions: Calculate [OH-] given [H3O+] in each aqueous solution and classify the solution as acidic or basic.
5. [H3O+] = 2.6 x 10-3 M
6. [H3O+] = 2.6 x 10-8 M
7. [H3O+] = 1.6 x 10-2 M
8. [H3O+] = 4.3 x 10-3 M
Instructions: Calculate the [H3O+] of solutions a and b; calculate the [OH-] solutions c and d.
9. pH = 2.76
10. pH = 3.65
11. pOH = 3.65
12. pOH = 6.87
Equilibrium and Le Chateleir’s Principal
Instructions: Write the equilibrium expression for each chemical equation.