Reference no: EM131230633
Assignment 1
Acids, Bases, Redox, Molarity, titration
1. Identify each of the following aqueous solutions as strong or weak, and as acid, base, or salt:
substance
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strong or weak
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acid, base, or salt
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(example) HCl
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strong
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acid
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NaOH
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|
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HCH3COO
|
|
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CaCl2
|
|
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Sr(OH)2
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|
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HClO4
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|
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2. Write the balanced molecular equation, the complete ionic equation, and the net ionic equation for the reaction of aqueous nitric acid with solid calcium hydroxide. Remember to include states.
3. A solution is prepared by dissolving 0.325 g of Mg(NO3)2in water to make 150.0 mL of solution. What is the molarity of the solution?
4. A 25.0 mL sample of acetonitrile, CH3CN (d = 0.786
mLg), is dissolved in enough water to produce 150.0 mL of solution. What is the molarity of acetonitrile in the solution?
5. Folic acid, C19H19N7O6, is important in many biological functions. What mass of folic acid is needed to prepare exactly 10.00 mL of a 0.250 M C19H19N7O6 aqueous solution?
6. A 25.00-mL solution of 0.350 M urea, CO(NH2)2, is diluted to 150.00 mL. What is the new molarity of the solution?
7. What is the oxidation number of the underlined element in:
a. NaOH c. H2PO4-
b. Na2CO3 d. Cr2O72-
8. For the following oxidation-reduction reactions, indicate which species are reduced and which are oxidized. [These redox reactions are not necessarily balanced-and you don't need to balance them-just identify the species reduced and the species oxidized.]
a. Fe(s) + Cu2+(aq) → Fe2+(aq) + Cu(s)
b. VO2+(aq) + MnO4-(aq) → VO2+(aq) + Mn2+(aq)
For problems 9 - 13, balance the given redox reactions in acidic solution. For problems 12 and 13 balance the redox reactions in basic solution.
9. S(s) + OCl-(aq) → SO32-(aq) + Cl-(aq)
10. Fe2+(aq) + Cr2O72-(aq) → Fe3+(aq) + Cr3+(aq)
11. S2O32-(aq) + MnO4-(aq) → SO42-(aq) + Mn2+(aq)
12. Fe(OH)3(s) + OCl-(aq) → FeO42-(aq) + Cl-(aq)
13. ClO2(aq) → ClO3-(aq) + Cl-(aq)
Assignment 2
All of the following questions are from Chapter 5:
1. Define each of the following terms:
a. energy
b. work
c. heat
2. What is kinetic energy, and what is the equation, given in Chapter 5, for kinetic energy?
3. List two different units for energy, give SI units where appropriate.
4. How is a food "Calorie" different from an energy "calorie"?
5. Restate the first law of thermodynamics in your own words.
6. Matching: Place the letter of the correct definition on the line in front of the given term.
calorimeter a. enthalpy change that accompanies a reaction
endothermic b. heat capacity of one gram of a substance
enthalpy c. E + PV
enthalpy of reaction d. portion not singled out for study
exothermic e. process in which the system absorbs heat
Hess's Law f. work involved in the compression or expansion of gas
pressure-volume work g. property of a system determined by specifying the system's condition
specific heat h. ?H for the overall reaction = sum of steps
standard enthalpy change i. portion singled out for study
state function j. enthalpy change when all substances are in their standard states
surroundings k. process in which the system loses heat
system l. device used to measure heat flow.