...and molar mass • Percent composition calculations • Empirical and molecular formula determinations • Chemical equations, amount of reactant and product calculations • Limiting reagents and reaction yield calculations Take Note: It is absolutely essential that you master the mole concept to do well on the quantitative aspects of AP Chemistry!! When solving quantitative problems on the Free Response section of the AP exam, supporting work must be shown to receive credit. Using dimensional analysis is a very powerful technique in solving problems. Be sure to report your answer to the correct number of significant figures (see Chapter 1 in this review book). Atomic mass and average atomic mass Atomic mass is the mass of an atom in atomic mass units (amu). One amu is defined as 1/12 of one C-12 atom. The C-12 isotope has a mass of exactly 12.000 amu. The C-12 isotope provides the relative scale for the masses of the other elements. Average atomic mass is the value reported on the periodic table, which takes into account the various isotopes of an element and their respective frequencies. To calculate the average atomic mass of an element, add up the different masses of the isotopes (using amu) multiplied by each isotope’s abundance (percent occurrence in nature divided by 100). Average atomic mass of element x = (isotope1 in amu × abundance1) + (isotope2 × abundance2) + (isotopen × abundancen) Example 1. Determining average atomic mass. The natural abundance of the C-12...
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...Dr. Hjorth-Gustin Chemistry 201 Lab November 8th, 2010 Synthesis and Analysis of Iron(III) Oxalate Complex Discussion This experiment initially involved the synthesis of an iron (III) oxalate complex with the general formula Kw[Fex(C2O4)y] zH2O. The variables x, y, and z were determined through the duration of the entire experiment. Part 1 involves the synthesis of an iron (III) oxalate complex. The iron is first presented in its Fe2+ form, so it must first be oxidized to Fe3+ before the oxalate ion will readily bind to it. Hydrogen peroxide is the oxidant of choice: 2Fe2+ (aq) + H2O2 (l) + 2H+ (aq) ---> 2Fe3+ (aq) + 2H2O (l), in acidic solution. The oxalate ion is then free to coordinate to the Fe3+ ion, forming a complex of Fe(C2O4). The oxalate ion is the conjugate base of the weak oxalic acid, H2C2O4. In the synthesis of the iron (III) oxalate complex, 0.8668g of the final lime-green crystals were obtained. The average percent of C2O4 was 59.00% and the theoretical yield was 53.74%. With this, the percent error came out to 9.79%. The percentage of Fe(III) in the green crystal obtained was 14.5%. Theoretically, it should have been around 10%. This lack of accuracy was quite difficult to recognize considering the calculations were approved by the professor but may have been due to incorrectly preparing the buffer. Apart from the usual human-mediated errors in the measuring and distribution of chemicals and in the readings of instrumental...
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...A mole is a unit of measurement, and must be based on something reproducible. In order to find the mole, one would need to use Avogadro Number, which is 6.02x1023. This allows one to understand the number of atoms and/or molecules in a mole of any specific substance. For example, a mole of hydrogen atoms is 6.02x1023 hydrogen atoms. Yet, it's more universally understood to write ‘Mole’ rather than 6.02x1023 . It’s commonly asked as to why the term ‘Mole’ was created when terms like grams and kilograms etc already exist. This is because Moles make it easier to convert between atoms, molecules and grams. The empirical formula is defined as a formula which tells the reader the ratio of elements that’s shown in the compound. However, it doesn’t...
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...games, thus a need to determine the likelihood of winning in games such as these evolved. The method created to suit this need is known as probability theory. Probability theory has been developed over hundreds of years, and is used to predict possible outcomes and assist in daily life. Probability has been developed and studied over time, and has been formed into formulas and theories that allow it to be used in a myriad of applications. Probability theory is a very important aspect of mathematics, and through the development...
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...full set of forecasted financial statements, the value estimates from a residual income model and a discounted cash flow model should yield identical results. The reason prior empirical studies (Penman and Sougiannis 1998 and Francis, Olsson, and Oswald 2000) found differences between the models is because of subtle errors in the implementation of the models. Penman (2001) understandably takes issue with our paper, claiming that we are wrong on three points. We feel quite confident in our original paper and will rebut each of Penman’s claims. Penman repeatedly states that he is interested in practical issues surrounding valuation. We share this interest; in fact, we were motivated to write our paper because of the common question raised by students and faculty: “Why do I get a different answer from my discounted cash flow valuation than from my residual income valuation?” We still maintain that, if carefully done, there will be no difference in the valuations from these theoretically equivalent models. Our paper shows exactly how to do this and illustrates commonly made mistakes. Further, any practical attempt to value a firm begins with forecasting future financial statements — earnings and book values at a minimum — and then constructs from these estimates the valuation attributes of interest. All the empirical papers discussed in our original paper started with a complete set of pro forma financial statements. We continue with the maintained assumption that these forecasts are available...
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...measurements * Radom error: all measurements have some level of random error they can be either positive( measure more than you actually do ) or negative errors( measure less then you usually do ) * Systematic error: always the same direction (either positive or negative) Precision and Accuracy * Precision : how reproducible each measurement is , how close each measurement is to the other measurements * Accuracy : how close the measured values are to the true value. Temperature Conversions (on the exam) Chemical Language * Elements (Na,Cl)- letters of the language * Chemical Formulas (NaCl)- words of the language Water Vs. Hydrogen Peroxide (on the exam) * The use of Hydrogen peroxide: nuclear, bomb, bleach hair,etc * Molecular formula : water: H2O, Hydrogen Peroxide : H2o2 * Empirical Formula: water HO, Hydrogen peroxide: HO * Structural Formula : water HOH, hydrogen peroxide: HOOH quetion: how many atoms of carbon, hydrogen, and oxygen are present in a single molucule of citric acid C3H5O(CO2H)3 Carbon: 6 Hydrogen :8 Oxygen: 7 Chemical Bonding * Bonds form between atoms when they share electrons * Different types of bonds: Ionic compounds: metal+nonmetal, Covalent compunds Naming Ionic Compounds Polyatomic Ions (see the syllabus) * Ions that are comprised of more than one atom; the atoms remain bound together. Naming COvalent Compounds The Mole * Def: the number of atoms contained in exactly 12g of carbon-12 ...
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...Grade 12 Chemistry Exam Coverage Topic | Reference | Measurement * Accuracy: Absolute error, Relative error * Precision: Range and Standard Deviation * Determining degree of precision of measuring devices * Significant figures * Errors in measurements * Random error * Systematic error: instrumental error, method error, personal error * Gross error | Lecture handoutsTextMath Toolbox 1.2p. 37-41 | Matter and its properties * Classification of Matter: substance and mixtures * Changes matter undergo: physical change and chemical change * Properties of matter * physical property: intensive & extensive * chemical property * Purification and Separation of matter: separation techniques | Lecture handouts TextChapter 1 1.1 p. 3-12 1.2 p. 13-26 | Atoms, Molecules and Ions * Structure of the atom: subatomic particles, the nuclear atom, isotopes, mass number, atomic number, isotope symbol * Ions: cations, anions, isotope symbol for ions * Naming ionic compounds * Naming covalent compounds | TextChapter 22.2 p. 60-682.3 p. 69-71Chapter 33.1 to 3.5p. 91-111 | Chemical Composition * Atomic mass: relative atomic mass, isotopic mass and isotopic abundance * Percent composition * Moles and Particles * Molar mass * Empirical Formula and Molecular Formula | TextChapter 22.4 p 72-74Chapter 44.1 to 4.3p. 130 - 148 | Quantities in Chemical Reactions * The meaning of a balanced reaction * Mole to mole conversion * mass to...
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...determined by the Wechsler Adult Intelligence Scale (WAIS) when the group of children has reached a mean age of 27.2 years. 4. The sample used in this research is a group of both males and females who were born in Copenhagen, Denmark between October 1959 and December 1961. The sample size is more than 3,000. a. The population that this sample seeks to represent is all the children of the world. 5. In this study, the researchers offer Wechsler Adult Intelligence Scale (WAIS) scores from the participating children as evidence to test their hypothesis. The evidence in this case is empirical because the researchers have observed the measureable data through testing. According to Merriam-Webster’s Collegiate Dictionary (2005), evidence can be defined as something which shows that something else exists or is true. Additionally, Merriam-Webster’s Collegiate Dictionary (2005), defines empirical as originating in or based on observation and experience. 6. The results of this study indicate that children who spent time breast feeding earned much...
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...Study Guide for Exame 2 CHAPTER 3: Stoichiometry * Stoichiometry – study of quantitative aspects of formulas and relations * The mole – SI unit for the amount of a substance. * The amount of matter that contains the same number of atoms as 12.0g of carbon -> 6.022 x 10^23 (Avogadro’s number) * Avogadro’s number – 6.022 x 10^23 * How to determine how many atoms of each element is in a compound: * (moles or grams)(6.022x10^23)(Number of atoms/1molecule) * Molar mass - Molar mass is the weight of one mole (or 6.022 x 1023 molecules) of any chemical compounds. * Mass % of an element in a compound: * ((Number of atoms of element)(atomic weight))/(Formula weight) * Empirical formula – Gives the lowest whole number ratio of atoms of each element in a compound (Grams)/(atomic weight) --- divide by lowest number on all * Molecular formula – gives actual whole number ratio of atoms of each element in each compound. (Molecular formula weight)/(Empirical formula weight) x compound * Formulas from analysis: * Structured formula – a formula that shows the atoms of a compound, their relative positions, and the bonds between them. * Isomers – compounds with the same molecular formula, but different properties and different arrangements of atoms * Writing chemical equations (symbols) : * + adding 2 or more chemicals together * -> Yields (Products) * (arrow forward and backward) reaction...
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...VALIDITY AND RELIABILITY For the statistical consultant working with social science researchers the estimation of reliability and validity is a task frequently encountered. Measurement issues differ in the social sciences in that they are related to the quantification of abstract, intangible and unobservable constructs. In many instances, then, the meaning of quantities is only inferred. Let us begin by a general description of the paradigm that we are dealing with. Most concepts in the behavioral sciences have meaning within the context of the theory that they are a part of. Each concept, thus, has an operational definition which is governed by the overarching theory. If a concept is involved in the testing of hypothesis to support the theory it has to be measured. So the first decision that the research is faced with is “how shall the concept be measured?” That is the type of measure. At a very broad level the type of measure can be observational, self-report, interview, etc. These types ultimately take shape of a more specific form like observation of ongoing activity, observing video-taped events, self-report measures like questionnaires that can be open-ended or close-ended, Likert-type scales, interviews that are structured, semi-structured or unstructured and open-ended or close-ended. Needless to say, each type of measure has specific types of issues that need to be addressed to make the measurement meaningful, accurate, and efficient. Another...
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...VALIDITY AND RELIABILITY For the statistical consultant working with social science researchers the estimation of reliability and validity is a task frequently encountered. Measurement issues differ in the social sciences in that they are related to the quantification of abstract, intangible and unobservable constructs. In many instances, then, the meaning of quantities is only inferred. Let us begin by a general description of the paradigm that we are dealing with. Most concepts in the behavioral sciences have meaning within the context of the theory that they are a part of. Each concept, thus, has an operational definition which is governed by the overarching theory. If a concept is involved in the testing of hypothesis to support the theory it has to be measured. So the first decision that the research is faced with is “how shall the concept be measured?” That is the type of measure. At a very broad level the type of measure can be observational, self-report, interview, etc. These types ultimately take shape of a more specific form like observation of ongoing activity, observing video-taped events, self-report measures like questionnaires that can be open-ended or close-ended, Likert-type scales, interviews that are structured, semi-structured or unstructured and open-ended or close-ended. Needless to say, each type of measure has specific types of issues that need to be addressed to make the measurement meaningful, accurate, and efficient. Another...
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...Here I developed a proposal on “Capital Structure Determinants of the Pharmaceutical Companies in Bangladesh: A study in Incepta pharmaceutical Company Limited”. The proposal will focus on the steps of research through several variables. The main findings of the research will be to find out the determinants of capital structure and find the most vital one through statistical analysis and interpretation. I highly appreciate you for creating such opportunity to work on the selected subject. The outcome of the research will help us to concentrate deeply in evaluating pharmaceutical companies in respect of capital structure and corporate strategies. Sincerely Ronald Halder ID – M 0910013 M.B.A 10th batch EXECUTIVE SUMMARY Determining the optimal capital structure is one of the most fundamental policy decisions faced by financial...
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...------------------------------------------------- Submitted to: ------------------------------------------------- Waperi,Evelyn P. ------------------------------------------------- ------------------------------------------------- My Learning Log 3rdGrading Period On November- December we tackle all about changes in matter and Gases. First we discuss about skill 2.1 convert number of roles to mass or vice versa and to the number of particles (atoms, ions, molecules) or vice versa. Second on Nov. 18, 2013 we tacle about skill 2.2 Derive the chemical formula of a compound given the mass ratio and the atomic masses of the elements present. Third on Nov. 19, 2013 we discuss about skill 2.3 Explain the law of conservation of mass. ( Empirical formula, Molecular formula and mass, mole, g/mole). Next on Nov.26, 2013 we discuss about determining the formula from percentage composition. And then on Nov. 26,2013 we discuss types of Chemical Reaction which is Combination, Decomposition, Single replacement and Double replacement . and we discuss also about explain the implied information derived from balanced equation. After we discuss all about changes in matter, we discuss all about changes, energy, and time. First discuss is all about Differentiate exothermic and endothermic reactions, which is the exothermic process ( releases beat while the endothermic process absorbs heat. ...
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...JOURNAL OF ECONOMICS AND FINANCE EDUCATION Volume 9 Number 2 Winter 2010 29 Using Microsoft Corporation to Demonstrate the Optimal Capital Structure Trade-off Theory John C. Gardner, Carl B. McGowan Jr., and Susan E. Moeller1 ABSTRACT In this paper, we apply the trade-off theory of capital structure to Microsoft. We use data for bond ratings, bond risk premiums, and levered CAPM betas to compute the cost of equity and the weighted average cost of capital for Microsoft at different debt levels. This study shows the impact of increasing financial leverage on WACC. As financial leverage increases, the WACC decreases until the optimal debt ratio is reached, after which, the WACC begins to rise. At this debt ratio, the value of Microsoft will be maximized. Our results indicate the optimal debt ratio for Microsoft is 37.5 percent. Introduction One of the most difficult concepts for finance students to learn and for faculty to teach is how a firm determines its optimal capital structure. While most corporate finance textbooks stress the importance of maximizing the value of the firm by minimizing its opportunity cost of capital, how a firm can actually achieve the appropriate debt–to–capital ratio is often a mystery. Brigham and Ehrhardt (2008) in Financial Management: Theory and Practice outline a framework that can be used by financial practitioners to determine a firm’s optimal capital structure. Modigliani and Miller (1958 and 1963) provide the basis for the trade-off...
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...all the investment decisions. • EPS and DPS were constant and never change while determining a value. • All the earnings of the company are distributed as dividends • The Company has a very long life Walter’s formula for determining MPS is as follow: P= (DPS/K) + [R(EPS-DPS)/K]/K Where: P: Market price/share DPS: Dividend/share EPS: Earning/share R: Firm’s average rate of return K: Firm’s cost of capital The market value is determined as the PV of two sources of income: 1. PV of constant stream of dividends (DPS/K). 2. PV of infinite stream of capital gains: R=(EPS-DPS)/K So the formula can be written as: P = {DPS+(R/k)(EPS-DPS)} /k The Walter's theory was also being criticized due to: [1, 2, 4] • No external financing assumptions, because investment decisions are all financed by retained earnings only and the company will need external financing for future new investments. • The cost of capital and internal rate of return was kept as constant which is also very hard to accept as due to future new investments, the business risks are more likely to increase or change. Thus in summary, the assumption made by this theory is unrealistic as the concept mentioned that the dividend policy has impact on the market value of the share. Gordon’s Model: This theory is also believe in the relevance of dividends on company’s value. This model states the current dividends as important in determining the value of the firm. The Gordon's theory on dividend policy stated that the company's...
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