1 Chemistry 1210 Final Exam Comprehensive Guide with Practice Problems Each topic is the focus of a slide from the lecture power points The following problems are compiled mainly from the text and mastering chemistry based off of the main topics covered in lecture and emphasized through professor assigned homework The order based on the sequence of what was taught in lecture Correct answers listed below each respective practice problem This guide utilizes concepts and practice problems from Mastering Chemistry Chemistry The Central Science by Theodore L Brown lecture slides from Professor Gustafson and material from previous exams throughout the semester Any of their work shown here is copyrighted and belongs to them respectively I do not own any of this information 2 TABLE OF CONTENTS Atomic Radii Pages 26 27 Balancing Equations Page 16 Bohr s Model Page 30 Chemical Formulas Pages 10 11 Concentrations Page 19 Covalent Bonding Page 44 Effective Nuclear Charge Page 25 Electron Affinities Pages 45 46 Electron Configuration Pages 38 40 Electron Spin and the Pauli Exclusion Principle Page 37 Empirical Formulas Pages 14 16 Ionic Bonding Page 43 Ionization Energy Pages 54 56 Ionic Radii Pages 28 29 Isotopes Pages 6 7 Law of Multiple Proportions Pages 9 10 Lewis Symbols the Octet Rule Pages 41 42 Mass Percent Page 14 Matter Pages 3 4 Measurement Pages 4 5 Metals Nonmetals and Metalloids Pages 48 50 Molar Heat Capacity Page 22 Net Ionic Equations Pages 18 19 Number of Neutrons Electrons Protons Page 10 Nomenclature Pages 11 12 Oxidation Numbers Pages 19 21 Precipitation Reactions Pages 12 14 Percent Actual Theoretical Yield Pages 17 18 Photon Emission Page 24 Significant Figures Pages 5 6 Specific Heat Pages 19 22 Stoichiometry Pages 7 9 The Heisenberg Uncertainty Principle Page 32 The Wave Behavior of Matter Page 31 Thermochemistry Pages 22 24 Trends for Selected Nonmetals Pages 51 53 Orbitals and their Energies in Many Electron Atoms Page 36 Orbitals and Quantum Numbers Pages 33 35 3 Topic 1 Matter section 1 2 page 7 in text Under normal conditions there are three distinct states of matter solids liquids and gases 1 Solids relatively rigid and have fixed shapes and volumes Example is a rock 2 Liquids have fixed volumes but flow to assume the shape of their containers for example a beverage in a can 3 Gases have neither fixed shapes nor fixed volumes and expand to completely fill their containers Example is air in an automobile tire Whereas the volume of gases strongly depends on their temperature and pressure the amount of force exerted on a given area the volumes of liquids and solids are virtually independent of temperature and pressure Matter can often change from one physical state to another in a process called a physical change For example liquid water can be heated to form a gas called steam or steam can be cooled to form liquid water However such changes of state do not affect the chemical composition of the substance pure substance any matter that has a fixed chemical composition and characteristic properties elements substances that cannot be decomposed into simpler substances On the molecular level each element is composed of only one kind of atom compounds substances composed of two or more elements they contain two or more kinds of atoms mixture combinations of two or more pure substances in variable proportions in which the individual substances retain their identity 4 Physical Properties can be observed without changing the identity and composition of the substance These properties include color odor density melting point boiling point and hardness Chemical Properties describe the way a substance may change or react to form other substances A common chemical property is flammability the ability of a substance to burn in the presence of oxygen Intensive Properties do not depend on the amount of sample being examined and are particularly useful in chemistry because many intensive properties can be used to identify substances Example temperature melting point Extensive Properties depend on the amount of sample with two examples being mass and volume Extensive properties relate to the amount of substance present Example Which of the following are intensive properties of a substance Temperature Color and Density are all intensive properties of a substance This question given on exam 1 Topic 2 Measurement section 1 4 page 15 in text A Temperature B Color C Weight D Density E Volume 1 C E 2 B C D 3 B 4 A B D 5 B D SI Base Units Prefixes 5 Topic 3 Significant Figures section 1 5 page 22 in text To determine the number of significant figures in a reported measurement read the number from left to right counting the digits starting with the first digit that is not zero In any measurement that is properly reported all nonzero digits are significant Rules for zeros Significant Figures in addition subtraction multiplication division For addition and subtraction the result has the same number of decimal places as the measurement with the fewest decimal places When the result contains more than the correct number of significant figures it must be rounded off Consider the following example in which the uncertain digits appear in color 6 For multiplication and division the result contains the same number of significant figures as the measurement with the fewest significant figures To illustrate this rule calculate the cost of the copper in an old penny that is pure copper Assume that the penny has a mass of 2 531 grams that it is essentially pure copper and that the price of copper is 67 cents per pound We can start by going from grams to pounds We then use the price of a pound of copper to calculate the cost of the copper metal There are four significant figures in both the mass of the penny 2 531 and the number of grams in a pound 453 6 But there are only two significant figures in the price of copper so the final answer can only have two significant figures Example How many significant figures should be retained in the result of the following calculation 12 00000 x 0 9893 13 00335 x 0 0107 By the order of operations we need to do multiplication first In the first part 12 00000 x 0 9893 we should have 4 significant figures 0 9893 has only 4 Therefore the answer for this part is 11 87 Similarly in the second part we should have 4 significant figures The answer for this part is 0 1391 Now we add the two results Since 11 87 is only up to 2 decimal places our final answer must also be up