1. Why is it incorrect to say that the results of a measurement were accurate but not precise?

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1 Summer Assignment Name: Record your answers in a Google document and be prepared to share your work with me at the beginning of the school year. Cite examples where appropriate. Show your work. Be concise and specific. In case solving problems (only) on a Google document will be challenging, please record your work in a separate paper and be ready to share the papers with me in the same time with the soft document. Use all the resources available for the completion of the tasks and use MLA format for proper citations. PART 1 1. Why is it incorrect to say that the results of a measurement were accurate but not precise? 2. Explain why the uncertainty of a measurement depends on the precision of the measuring device. What does the % uncertainty tell you about a measured or derived value? 3. A student analyzed a sample of rock for its calcium content and obtained the following results: 14.92% 14.91% 14.88% 14.91% The actual amount of calcium in the sample is 15.70%. What conclusion can you draw about the accuracy and precision of the results? Calculate the % error. 4. A rule of thumb in designing experiments is to avoid a result that is the small difference between two large measured quantities. In terms of uncertainties in measurement, why is this good advice? What would a corollary of this statement be? 5. Compare the density of the hydrogen nucleus to that of the atom. What does this say about the nature of atoms? 6. Early alchemists used to do an experiment where water was boiled for several days in a sealed glass container. Eventually some white solid residue would appear in the bottom of the flask. They interpreted this to mean that some of the water was being converted to earth. Later Antoine Lavoisier repeated this experiment and found that the water weighed the same before and after boiling, and that the flask and residue weighed the same as the flask before heating. Were the alchemists correct? Explain what really happened. 7. What information do we get from chemical formulas? Using CaCO 3, as an example identify each of the following: The number of each element in a formula unit The mass of one mole Two ions & The mass of oxygen in moles 8. The atomic mass of boron given on the periodic table is g/mole, yet no individual atom of boron has this mass. Explain 9. What experimental evidence supports the existence of electron energy levels? 10. What is the color of the high energy end of the visible spectrum? Would they have longer or shorter wavelengths? 11. What is the color of the low energy end of the visible spectrum? Would they have longer or shorter wavelengths? 12. How do the energy and wavelength of a transition between n=1 to n=2 compare to a transition between n=3 and n=4? Why is there a difference? 13. Which of the following represents electron configurations of an atom in an excited state? Identify each element and indicate the correct ground state configuration. a. 1s 2 2s 2 3p 1 b. 1s 2 2s 2 2p 3 c. [Ar]4s 1 4p Which type of radioactive decay results in a new element being formed with no change in mass? Why?

2 16. Which type of decay results in a change in both the mass and atomic number of an element? Why? 17. A beta particle has the same properties as an electron. Electrons are not found in the nucleus so how is it possible for a nucleus to undergo beta decay? What changes take place in this process? 18. How can the half-life of a radioactive isotope be used to date very old objects? 19. Alchemists were always trying to find ways of turning lead into gold. Why were they destined to fail? 20. Determine the number of protons, neutrons and electrons in each of the following species: a. 37 Cl -1 b. 22 Ne c. 85 Sr Which of the following has the same # of neutrons as 54 Cr? a. 50 Ti b. 51 V c. 54 Fe d. 55 Mn 22. Which of the following relationships are not true? PART 2 a. There is an inverse relationship between wavelength and energy. b. The density of the nucleus is > the density of the atom. c. The particles of a gas are close together and held in fixed positions. d. Photons of light are emitted when an electron is excited from the ground state.. This part of assignment will be submitted on line only. Provide examples for each explanation. Be ready to share the document with me at the beginning of the year. 1. Describe how to calculate the theoretical yield. 2. Describe how to determine an empirical formula from experimental masses. Identify what would need to be known in order to also determine the molecular formula. 3. Describe how to determine the % composition (by mass) of a compound. 4. Explain how to predict the products for a double replacement reaction. 5. Explain how to balance an equation for a combustion reaction. 6. Explain how to determine the number of hydrogen atoms in a given mass of a compound containing hydrogen. 7. If a reactant is in solution, explain how the moles of reactant are determined and how the concentration of the soluble product can be determined. 8. Explain how the rules of sig figs are used to determine how to round your answer in stoichiometric calculations. Solve each of the following showing all work, units and rounding answers to the proper number of sig figs. This document must be submitted in a separate paper (hard copy only). Part 1: 1. Write the formula for each of the following: Molar Mass # ions (1M) a. Iron III sulfate b. Bismuth V nitrate c. Ammonium phosphate d. Copper II carbonate e. Gold III hydroxide 2. Determine the molar mass of each compound in #1 above. Place your answer in the second column above. 3. Indicate the total # of ions present in a 1M solution of each compound in #1 above. Place your answer in the third column above.

3 4. Calculate the % composition of each element in #1c above. 5. Which compound has the greatest number of atoms? 6. Which compound has the greatest number of elements? 7. Which compound in #1 has the greatest number of oxygen atoms? 8. Which compound in #1 above has the lowest % oxygen? 9. Which compound has the highest % metal? 10. If you have a 10.0 g sample of each compound, which sample would the most moles? How many moles would it have? 11. If you have a 10.0g sample of each compound dissolved in 500 ml, which sample would have the least moles of ions? How many moles of each ion of this compound would be present in this solution? What would be the total ion concentration in this solution? What would be the metal ion concentration in this solution? 12. Which compound in a solution as described in #11 would have the greatest conductivity? Why? 13. Calculate each of the following using the compounds found in #1 above: a. The number of moles in a 32.5g sample of #1a. b. The mass of moles of #1b. c. The number of atoms in 5.00g of #1c. d. The mass of 2.3 x molecules of 1d. e. The number of oxygen atoms in 25.0g of #1e. f. The mass of a sample of 1d that contains 3.00 x sulfur atoms. g. The mass of 1a that has the same # moles as 7.35g sample of 1d. h. The mass of 1b that has the same amount of oxygen as 1.00g of 1d. i. The mass of 1c that would be present in 300ml of a 0.15M soln of 1c. j. The mass of 1b that would have the same total ion concentration as 250ml of a 2.0M soln of 1e. Part 2: Empirical formulas 1. Determine the empirical formula of a compound that is 47.08%C, 6.59%H and 46.33g O. 2. A sample of urea contains 1.121g N, 0.161g H, 0.480g C and 0.640g O, What is its empirical formula? What was the mass of the sample analyzed? Part 3: 1. Write and balance the equation for each of the following: a. The synthesis of ammonia gas from its elements. b. The decomposition of solid aluminum oxide into its elements. c. The reaction of chlorine gas with aqueous iron III bromide. What type of reaction is this? d. The reaction of solid sodium sulfate with aqueous chromium III nitrate. What type of reaction is this? Which product would be the ppt? e. The combustion of liquid ethanol. f. The neutralization of 1M nitric acid with 1M barium hydroxide. What type of reaction is this? 2. Which reaction above has the highest sum of its coefficients? What is this sum? 3. Which reaction above has the least moles of reactants? How many are there? 4. Which reactions above occur in solution?

4 5. For which reactions are the moles of product greater than the moles of reactants? 6. For reaction #1a, if you react 10.0g of nitrogen with 3.00g of hydrogen, what volume of ammonia would be produced at STP? Identify the limiting reactant. 7. For reaction # 1d, if you react 1.50g of sodium sulfate with 60ml of 0.15M solution of chromium nitrate, what mass of the chromium sulfate compound would be formed? Identify the limiting reactant. 8. For reaction 1f, if 50ml of 1.0M nitric acid is reacted with 25 ml of 1.0M barium hydroxide, what concentration of salt will you have after neutralization? Identify the limiting reactant. 9. For the reaction in 1c, if 100ml of 0.1M iron III bromide is reacted completely, what volume of bromine gas would be produced at 25 o C and 0.96atm? 10. When the experiment in #6 above was performed only 14.6L of ammonia was collected. Calculate the % yield. 11. When the experiment in #7 above was performed only 1.28g of ppt was recovered. What was the % error? 12. When the experiment in #8 above was performed the molarity of the salt was found to be only 0.28M. What was the % error? 13. When the experiment in #9 above was performed the volume of the gas collected was only 32.5 ml. What was the % yield? 14. The H for the reaction in #1a is 92 kj. How much heat would be produced from the reaction in #6 above. PART 3 Read the definition of command terms used in IB program. For each command term bolded from the list create a flash card AND a poster (A4 format) with your choice of 10 command terms (out of 18). Your POSTERS must represent your understanding of each command term could be a picture, a mnemonic, a cartoon, an example of antonym, anything that help you remember how to use that word in a task. Your posters must be ready to be shared with your peers in the first day of course. Command Terms from the International Baccalaureate (IB) Program/Across Disciplines Analyze Annotate Apply Appraise Argue Calculate Classify Comment Compare Compare & Contrast Break down in order to bring out the essential elements or structure. To identify parts and relationships, and to interpret information to reach conclusions. Add brief notes to a diagram or graph. Use knowledge and understanding in response to a given situation or real circumstances. To evaluate, judge or consider text or a piece of work. Challenge or debate an issue or idea with the purpose of persuading or committing someone else to a particular stance or action. Obtain a numerical answer showing the relevant stages in the working. Arrange or order by class or category. Give a judgment based on a given statement or result of a calculation. Give an account of the similarities and differences between two (or more) items or situations, referring to both (all) of them throughout. Give an account of the similarities and differences between two (or more) items or situations, referring to both (all) of them throughout.

5 Construct Contrast Deduce Define Display information in a diagrammatic or logical form. Give an account of the differences between two (or more) items or situations, referring to both (all) of them throughout. Reach a conclusion from the information given. Give the precise meaning of a word, phrase, concept or physical quantity. Demonstrate Prove or make clear by reasoning or evidence, illustrating with examples or practical application. Derive Describe Design Determine Discuss Distinguish Manipulate a mathematical relationship to give a new equation or relationship. Give a detailed account or picture of a situation, event, pattern or process. Produce a plan, simulation or model. Obtain the only possible answer. Offer a considered and balanced review that includes a range of arguments, factors or hypotheses. Opinions or conclusions should be presented clearly and supported by appropriate evidence. Make clear the differences between two or more concepts or items.

6 Document Estimate Evaluate Examine Exemplify Explain To credit sources of information used by referencing (or citing) following one recognized referencing system. References should be included in the text and also at the end of the piece of work in a reference list or bibliography. Find an approximate value for an unknown quantity. To assess the implications and limitations; to make judgments about the ideas, works, solutions or methods in relation to selected criteria. Consider an argument or concept in a way that uncovers the assumptions and interrelationships of the issue. Represent with an example. Give a detailed account including reasons or causes. Explore Formulate Identify Infer Interpret Investigate Justify Label List Measure Outline Predict Present Prove Recall Reflect Recognize Undertake a systematic process of discovery. Express precisely and systematically the relevant concept(s) or argument(s). Provide an answer from a number of possibilities. Recognize and state briefly a distinguishing factor or feature. Deduce; reason from premises to a conclusion. Listen or read beyond what has been literally expressed. Use knowledge and understanding to recognize trends and draw conclusions from given information. Observe, study, or make a detailed and systematic examination, in order to establish facts and reach new conclusions. Give valid reasons or evidence to support an answer or conclusion. Add title, labels or brief explanation(s) to a diagram or graph. Give a sequence of brief answers with no explanation. Find the value for a quality. Give a brief account or summary. Give an expected result of an upcoming action or event. Offer for display, observation, examination or consideration. Use a sequence of logical steps to obtain the required result in a formal way. Recognize or identify To think about deeply; consider. Identify or recall particular features.

7 Show Sketch Solve State Suggest Summarize To What should be Extent Use Give steps in a derivation or calculation. Represent by means of a diagram or graph (labeled as appropriate). The sketch should give a general idea of the required shape or relationship, and should include relevant features. Obtain the answer(s) using algebraic and/or numerical and/or graphical methods. Give a specific name, value or other brief answer without explanation or calculation. Propose a solution, hypothesis or other possible answer. Abstract a general theme or major point(s). Consider the merits or otherwise of an argument or concept. Opinions and conclusions presented clearly and supported with appropriate evidence and sound judgment. Apply knowledge or rules to put theory into practice. Additional Command Terms Commonly Found on Constructed Exam Questions AGREE OR DISAGREE Support or refute a statement; give the positive or negative features; express an informed opinion one way or the other; list the advantages for or against. ASSESS THE DEGREE Command words such as these strongly suggest to the student that two schools of thought exist about a given subject. These questions often involve weighing the relative merit of conflicting points of view; e.g., negative vs. positive, strong vs. weak, fundamental vs. immediate. GIVE THE SIGNIFICANCE OF Present information which determines the importance of an event or issue. Quite often used to show causation. SUPPORT / REFUTE Give the points in favor of, or opposed to, a predetermined point of view or particular position. Also see AGREE / DISAGREE While students should generally support or refute the given statement, their responses may include opposing points. Common Variations of Previously Stated Command Terms Assess the relative importance of Critically assess Would you agree How far Weigh Advise Organize What factors Show how What trends Draw on your knowledge Illustrate Account for Hypothesize Integrate Review Criticize

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General Chemistry I Final Exam 100 pts Fall 2010

General Chemistry I Final Exam 100 pts Fall 2010 Name This is a closed-book exam: the only reference materials you may use are a periodic table of the elements, a table of enthalpies of formation, and