Directions: It is important that you provide answers in your own words. Please focus only on information from the text/eBook to create your own solutions. Please do not use direct information from an outside source (especially copying and pasting from an "answer" website). Use of direct information from an outside source is against school policy. All answers will be checked for plagiarism. Instances of plagiarism can result in probation or possible dismissal from the school.
Please be sure to follow all guidelines (number of sentences/showing all calculations) and to provide the correct metric units of measure. All questions are 5 points (1 point for sentence number /units).
1. A student collected the following data for a fixed volume of gas:
|
Temperature (°C)
|
Pressure (mm of Hg)
|
|
10
|
726
|
|
20
|
750
|
|
40
|
800
|
|
70
|
880
|
|
100
|
960
|
|
150
|
???
|
Fill in the missing data point. Show all calculations leading to an answer.
2. You are given a clear solution of KNO3. Using 3 - 4 sentences (in your own words) explain how you would determine if the solution is unsaturated, saturated or supersaturated.
3. Explain why gasoline will not dissolve in water.
4. Explain in 3 - 4 sentences (in your own words) how perspiration helps keep you cool on a hot day.
5. You have two sealed jars of water at the same temperature. In the first jar there is a large amount of water. In the second jar there is a small amount of water. Using 3 -4 sentences explain how the vapor pressure of water in the first jar compares with the vapor pressure of water in the second jar.
6. Using 3 - 4 sentences explain (in your own words) why water expands when it freezes?
7. Using your knowledge of colligative properties explain whether sodium chloride or calcium chloride would be a more effective substance to melt the ice on a slick sidewalk. Use 3 - 4 sentences in your explanation.
8. When a 2.5 mol of sugar (C12H22O11) are added to a certain amount of water the boiling point is raised by 1 Celsius degree. If 2.5 mol of aluminum nitrate is added to the same amount of water, by how much will the boiling point be changed? Show all calculations leading to your answer OR use 3 - 4 sentences to explain your answer.
9. If 5.40 kcal of heat is added to 1.00 kg of water at 100°C, how much steam at 100°C is produced? Show all calculations leading to an answer.
10. The freezing of water at 0°C can be represented as follows:
H2O (l) ↔ H2O(s)
The density of liquid water is 1.00 g/cm3. The density of ice is 0.92 g/cm3. In 3 - 4 sentences explain why applying pressure causes ice to melt.
11. The Kw of water varies with temperature. Calculate the pH of water at 46°C with a Kw = 1.219 x 10-14. Show all calculations leading to an answer.
12. Calculate the hydroxide ion concentration of a solution with pH = 3.25. Show all calculations leading to an answer.
13. What salt results from the neutralization of phosphoric acid with potassium hydroxide?
14. What is the oxidation number of chlorine in Al(ClO4)3?
15. Which element is oxidized in the following reaction:
CuO(s) + H2 (g) à Cu(s) + H2O (l)
16. Why must the number of electrons lost equal the number of electrons gained in every redox reaction? Use 3 - 4 sentences in your own words to address this question.
17. The following unbalanced equation describes the reaction that can occur when lead (II) sulfide reacts with oxygen gas to produce lead (II) oxide and sulfur dioxide gas:
PbS + O2 à PbO + SO2
Balance the equation and describe in words the electron transfer(s) that takes place.
18. What type of radiation is emitted when chromium-51 decays into manganese-51? Show the nuclear equation that leads you to this answer.
19. A radioactive nucleus alpha decays to yield a sodium-24 nucleus in 14.8 hours. What was the identity of the original nucleus? Show the nuclear equation that leads you to this answer.
20. Iron-59 has a half-life of 45.1 days. How old is an iron nail if the Fe-59 content is 25% that of a new sample of iron? Show all calculations leading to a solution.
Directions: It is important that you provide answers in your own words. Please focus only on information from the text/eBook to create your own solutions. Please do not use direct information from an outside source (especially copying and pasting from an "answer" website). Use of direct information from an outside source is against school policy. All answers will be checked for plagiarism. Instances of plagiarism can result in probation or possible dismissal from the school.
Please be sure to follow all guidelines (number of sentences/showing all calculations) and to provide the correct metric units of measure. All questions are 5 points (1 point for sentence number /units).
21. Experimental Design: From the work you have done this semester, choose a topic and design an experiment you would be able to perform. In your design (1) state your hypothesis, (2) identify your dependent and (3) independent variables, (4) your control conditions and (5) describe your experimental procedure.
22. Perform this operation and report the answer to the correct number of significant figures: What is the mass of a cube of aluminum that is 4.0 cm on each edge? The density of aluminum is 2.7 g/cm3. Show all calculations leading to an answer.
23. Explain why a model of the atom is crucial to understanding chemistry and in explaining the behavior of matter. Use 3 - 4 sentences in your explanation.
24. What parts of Dalton's atomic theory no longer agree with the current picture of the atom? Provide an answer using 3 - 4 sentences in your own words.
25. If an element has 12 protons and 17 neutrons, how many electrons must it have?
26. Why are the atomic masses of elements usually decimal numbers? Provide an answer using 3 - 4 sentences in your own words.
27. In 3 - 4 sentences and in your own words describe how Mendeleev's periodic table differs from Moseley's.
28. What is the electron configuration of the element with 27 protons?
29. How many electrons are in the highest energy orbital of the element copper?
30. How many dots should be indicated in the electron dot structure of arsenic?
31. Why is the first ionization energy of a nonmetal much higher than that of an alkali metal in its same period? Provide an answer using 3 - 4 sentences in your own words.
32. Why do compounds with strong intermolecular attractive forces have higher boiling points than compounds with weak intermolecular attractive forces? Provide an answer using 3 - 4 sentences and in your own words.
33. Write the formula for iron (III) sulfate.
34. What is the reason the group 13 metals have a typical charge of 3+?
35. Why does one mole of carbon atoms have a smaller mass than one mole of sulfur atoms?
36. What is the percentage of nitrogen in N2O? Show all calculations leading to an answer.
37. How many non-bonding electrons does phosphorus have?
38. Complete and balance this reaction: sulfuric acid reacts with barium chloride
39. Identify the precipitate in this reaction: calcium nitrate reacts with sodium phosphate.
40. The following is a Limiting Reactant problem:
Magnesium nitride is formed in the reaction of magnesium metal with nitrogen gas in this reaction: 3 Mg(s) + N2(g) à Mg3N2(s)
How many grams of product are formed from 2.0 mol of N2 (g) and 8.0 mol of Mg(s)? Show all calculations leading to an answer.