Text @Sumapc to 81010 for Quick Links and Info REFERENCES
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**Join Remind101: Text @sumapc to 81010 for quick links and info June 4, 2019 Dear Prospective AP Chemistry Students and Parents, Advanced Placement Chemistry is a course designed to be the equivalent of the general chemistry course taken during the first year of college by science majors. For some students, this course enables them to undertake, as freshmen, second year work in the chemistry sequence or to register for courses in other fields where general chemistry is a prerequisite. For other students, the AP Chemistry course fulfills the laboratory science requirement and frees time for other courses. AP Chemistry is a rigorous math-based course, with a strong laboratory component. It is intended for students who have demonstrated a willingness to commit considerable time to studying and completing assignments outside of class, and who have successfully completed a prior course in chemistry, preferably Honors Chemistry. Since passing the AP exam may qualify the student to bypass a first-year college chemistry course, AP Chemistry should not be considered "college prep." Rather, this is a college class, with college level expectations for behavior, participation, and effort. REQUIRED materials: · Scientific calculator or graphing calculator (must have LOG key) th · TEXTBOOK: Chemistry, 10 edition by Brown, Lemay, & Bursten (You may use the link below if you need for now) · Summer Packet Assignment: The AP Chemistry exam is offered in the beginning of May, so we require that students complete summer review requirements prior to the start of school. This is vital in assuring that our students are guided in the best way possible. *Note: We will be utilizing the WebAssign Online Homework and the billing is applied per class. RECOMMENDED material: There are so many free online sources AP Chem Course & Exam Description (The best resource provided by the College Board with details of the exam) AP Chem Review of Everything (created by AP Chem teachers) http://blog.prepscholar.com/ap-chemistry-study-guide http://www.sciencegeek.net/APchemistry/APtaters/directory.shtml http://blog.prepscholar.com/best-ap-chemistry-books (Read this blog before you decide to spend money) Textbook: https://drive.google.com/file/d/0B1Zhp01hnSI_WVVqQ1VYZ3hUdE0/view Mrs. Ismail’s website for video links: www.mervetismail.com The SUMMER ASSIGNMENT checklist is typed on the first page of the Basics of Chemistry Packet. This material should be a review of material learned in your prior chemistry course. Please follow those directions carefully. An exam over the material will occur the 3rd full week of class. *The SUMMER PACKET will be collected the FIRST DAY OF SCHOOL.* Please be sure to spend the time to skim through the entire packet very carefully. We hope you are excited to be enrolled in this class. We look forward to meeting all of you in the fall. Have a wonderful summer! Sincerely, Mrs. Matynowski & Mrs. Ismail West Bloomfield High School For questions or problems, please e-mail: [email protected] REFERENCES: (p2-7) Predicting Chemical Reactions Notes The products of a chemical reaction may often be predicted by applying known facts about common reaction types. Only 5 general types of reactions will be considered: Combustion, Single Displacement, Double Displacement, Synthesis, and Decomposition (Analysis). A COMBUSTION REACTION occurs when an element/compound reacts with oxygen(O2), often producing energy in the form of heat/light. Ex: CH4 + 2 O2 → CO2 + 2 H2O + heat/light **Hydrocarbons are compounds made up mainly of carbon and hydrogen (they also may contain oxygen or nitrogen). When hydrocarbons react with oxygen gas, they from CO2 + H2O **A rhyme to help you remember: “Reacting O2 with “CH or CHO” always produces “CO(2) and H(2)O”! A SINGLE DISPLACEMENT REACTION occurs when one element displaces another in a compound. The general form is: element + compound → element + compound A + BC → B + AC ex: Zn + 2HCl → H + ZnCl 2 2 We call this: “SPORTS SUBSTITUTION” A DOUBLE DISPLACEMENT REACTION occurs when the cations and anions of the two reactants are interchanged. The general form is: compound + compound → compound + compound AB + CD → AD + CB Ex: FeS + 2HCl → FeCl2 + H2S A SYNTHESIS REACTION occurs when two or more elements or compounds are combined to form ONE more complex substance. The general form is: element/cmpd + element/cmpd → compound ex: Fe + S → FeS A DECOMPOSITION (ANALYSIS) REACTION occurs when energy in the form of heat, light, electricity, or mechanical shock is supplied. A compound may decompose to form simpler compounds and/or elements.The general form is: compound → two or more substance. There are six general types: *You do NOT need to memorize the following, just apply the statement. 1. Some oxy-acids, when heated, decompose to form water and non-metal oxide. Ex: H2CO3 → H2O + CO2 2. Some metallic hydroxides,when heated, decompose to form metal oxide & water. Ex: Ca(OH)2 → CaO + H2O 3. Some metallic carbonates, when heated, decompose to form the metal oxide and carbon dioxide. Ex: Li2CO3 → Li2O + CO2 4. Some metallic chlorates, when heated, decompose to form the metal chloride and oxygen gas. Ex: 2KClO3 → 2KCl + 3O2 5. Most metallic oxides are stable, but a few decompose when heated to form the metal and oxygen gas. Ex: 2HgO → 2Hg + O 2 6. Some compounds may be decomposed by electricity, called electrolysis, into their elements. Ex: 2NaCl → 2Na + Cl 2 Balancing Equations and Identifying Reactions Synthesis / Combination 2> smaller compounds/elements → 1 compound Decomposition 1 compound → >2 smaller compd / elements Combustion reaction with O2 as a reactant → Single Replacement “Sports Substitution” AB + B → AC + B Double Replacement “Double Dating” AB + CD → AD + CB Organic Alkane Naming Throughout the year, you will see problems involving compounds made primarily of C and H. These are called hydrocarbons, or alkanes. You should become familiar with the first 10 normal alkanes. Methane CH4 Hexane C6H14 Ethane C2H6 Heptane C7H16 Propane C3H8 Octane C8H18 Butane C4H10 Nonane C9H20 Pentane C5H12 Decane C10H22 A handy way to remember the top 4 is with “Me Eat Peanut Butter!” You may use the “times 2, plus 2” rule to remember the ratio of C to H. e.g. octane: I know “octa-“ refers to 8 carbons, so 8 x 2 = 16 + 2 = 18 H Another interesting fact about hydrocarbons: When you burn (combustion) compounds with H and C (generally with O also), you always produce CO2 + H2O. ex: CH4(g) + 2O2 (g) → CO2 (g) + 2H2O (g) Mass Percent The equation for the % of anything is: % = “X” (your focus) x 100 TOTAL Know %, want grams: (work backwards): Shift your % decimal 2 loops back, multiply by TOTAL! *If you are given a compound, asked for % of an element: Add up molar masses & use the equation above. *If you are given a reaction and you want to know the % element in an impure substance: (1) Figure out the mass of the element in question in the compound on the product side by finding % element in the compound ((X/total) x 100)). (2) Use the % to find the grams of the element in the given product sample (Shift your % decimal…) (3) Since the grams of the element should be equal on R & P side, grams element x 100 total grams Reactant Unknown CH/CHO Assistance Sheet Use this information for #68-73 Before you begin the problem, analyze that you are solving for an EMPIRICAL and MOLECULAR FOR”MOL”A. So, you need to find “MOLES” of C, H, and O to get the answer. 1. Write the equation for the combustion reaction. Then, write the values given below each substance. 2. · Find the %C in the CO2 and multiply this constant value (using the decimal form of the percent) by the total grams of CO2. Underline this value, #g C. · Change #g C→ #moles C and underline your answer. · Repeat this for the H in H2O. 3. Now, you have to deal with the oxygen. The problem is that the O appears in both of the reactants, making it hard to find exactly how much is only in the {CHO}, not in the O2. But, you know by the Law of Conservation of Mass how much C and H are in {CHO}, because the amount present in the products must be equal to what is present in the reactants and each of these only appear in one place on either side. You also were given the amount of {CHO} that you started with; the C+H+O = {CHO}! · #grams of {CHO} - #grams C - #grams H = #grams O · change #grams O → #moles O 4. Write the for”MOL”a. Divide by the lowest number to get whole numbers greater than 1. This whole number, reduced ratio between the atoms is called the EMPIRICAL for“mol”a. 5. For the molecular for”mol”a, use the “ME” equation to find your “multiplier”: Molar mass of MOLECULAR FORMULA = Molar mass of EMPIRICAL FORMULA Multiply the empirical formula by this value to find the molecular formula. YOU ARE DONE!! Sample problem: Vanillin (methyl vanillin) is used in flavorings, fragrances, pharmaceuticals, and perfumes is made of carbon, hydrogen, and oxygen. If 3.00g of the substance is combusted and 6.93 grams of CO2 and 1.42 grams of water are produced, what is the empirical formula for the substance? The molar mass of the molecular formula is 456 g/mol. Find the molecular formula. AP Chemistry Helpful Equations Guide The following are optional ways to solve particular types of problems. Some are simple rules we will follow when solving problems. Molecular Weights *Using the NEW AP EXAM P.T, use the entire # from the periodic table. (units: g/mol) Mass % % X = grams of element X x 100 (a.k.a.