AP Chemistry Summer Assignment 2012 The summer assignment is designed to help you practice: - writing chemical formulas, names, and chemical equations - reaction types - predicting reaction products - the solubility rules - the activity series - stoichiometry The ions/polyatomic ions, solubility rules, and activity series will need to be memorized. (If you need an ion/polyatomic ion list, solubility chart, or activity series contact Mrs. Luzier.) The College Board will expect you to know these for the AP exam in May. They do not allow those lists/tables to be used. They will always give you a periodic table. The periodic table though will only have the chemical symbols and numbers on it, not the names of the elements. This summer assignment will be due the first week of classes. Within the first week of classes, we will have a test on this material.
AP Chemistry Summer Assignment 2012 Name: Synthesis/Combination Reactions Predict the products of each of the following reactions. Write the names of the products. Write the chemical formulas for all reactants and products. Balance each chemical equation. Don t forget: Hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine and iodine are diatomic. 1. magnesium and oxygen 2. iron and oxygen 3. carbon and oxygen 4. hydrogen and oxygen 5. potassium and iodine 6. strontium and bromine 7. sodium and fluorine 8. calcium oxide and water 9. sulfur dioxide and water 10. calcium oxide and sulfur dioxide
Decomposition Reactions Predict the products of the following decomposition reactions. Write the names of the products. Write the chemical formulas for all reactants and products. Balance each chemical equation. Don t forget: Hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine and iodine are diatomic. 1. water 2. calcium carbonate 3. calcium hydroxide 4. potassium chlorate 5. carbonic acid 6. sulfuric acid 7. mercury (II) oxide 8. sodium chlorate 9. sodium nitrate 10. copper(ii) chloride
(Single) Replacement/(Single) Displacement Reactions Use the Activity Series page attached to determine which of the following reactions would occur. If the reaction would not occur, then write No Reaction. If the reaction would occur, then predict the products of each of the following reactions. Write the names of the products for each reaction that would occur. Write the chemical formulas for the reactants and products of the equations that will occur. Balance the chemical equation for the reactions that will occur. Write an ionic equation and then eliminate any spectator ions in order to write a net ionic equation for each reaction that will occur. Don t forget: Hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine and iodine are diatomic. Example 1: solid copper and aqueous silver nitrate silver and copper (II) nitrate (Copper is above silver in the activity series. This means that it is more reactive than silver and will easily replace it.) Cu (s) + 2AgNO3 (aq) 2Ag (s) + Cu(NO3)2 (aq) Cu (s) + 2Ag + (aq) + 2NO3 - (aq) 2Ag (s) + Cu 2+ (aq) + 2NO3 - (aq) Net ionic: Cu (s) + 2Ag + (aq) 2Ag (s) + Cu 2+ (aq) Example 2: solid silver and aqueous copper (II) nitrate No Reaction (Silver is below copper in the activity series. This means that it is less reactive than copper. Silver would not be able to shove copper out of the way. There would be no reaction here.) 1. solid aluminum and aqueous lead (II) nitrate 2. solid sodium and water (liquid) 3. bromine (liquid) and aqueous potassium chloride
4. solid magnesium and hydrochloric acid (aqueous) 5. fluorine gas and sodium chloride 6. solid aluminum and aqueous iron (III) oxide 7. solid zinc and aqueous lead (II) nitrate 8. solid copper and aqueous iron (II) sulfate 9. solid nickel and aqueous copper (II) chloride 10. solid lead and aqueous zinc chloride
Double Displacement/Double Replacement/ Metathesis Reactions Predict the products of the following reactions. Write the names of the products. Write the chemical formulas for all reactants and products. Assume both reactants are aqueous unless another state is specifically indicated. Use the solubility rules to determine the states of each product. Balance each chemical equation. Write an ionic equation and then eliminate any spectator ions in order to write a net ionic equation for each reaction. Example: Sodium chloride and silver nitrate sodium nitrate and silver chloride NaCl (aq) + AgNO3 (aq) NaNO3 (aq) + AgCl (s) Na + (aq) + Cl - (aq) + Ag + (aq) + NO3 - (aq) Na + (aq) + NO3 - (aq) + AgCl (s) Net ionic: Ag + (aq) + Cl - (aq) AgCl (s) 1. potassium iodide and lead (II) nitrate 2. iron (II) sulfide and hydrochloric acid 3. hydrochloric acid and sodium hydroxide 4. nitric acid and calcium hydroxide
5. copper (II) chloride and sodium sulfide 6. lead (II) acetate and hydrogen sulfide 7. lithium hydroxide and iron (III) nitrate 8. aluminum hydroxide and sulfuric acid 9. hydrogen sulfide gas and silver nitrate 10. sodium phosphate and calcium chloride
Combustion Reactions In a combustion reaction, some organic compound is usually burned in air (oxygen). The products of each of these combustion reactions will be carbon dioxide and water. Write the names of the products. Write the chemical formulas for all reactants and products. Balance each chemical equation. Don t forget: Hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine and iodine are diatomic. The first reactant in each of these reactions is an organic compound. Draw the structure of the first reactant, the organic reactant, in each of the following reactions. 1. methanol and oxygen 2. ethanal and oxygen 3. propanone and oxygen 4. butanoic acid and oxygen 5. pentane and oxygen 6. 2-hexene and oxygen 7. 3-heptyne and oxygen 8. 2,3-dimethyloctane and oxygen
Stoichiometry Practice Mole-Mole Conversions Use the equations from the first page of this packet to answer the following questions. 1. How many moles of magnesium oxide could be produced from 5.25 moles of magnesium and excess oxygen? 2. How many moles of sodium would be required to make 4.50 moles of sodium fluoride? 3. How many moles of diatomic bromine would be required to make 2.00 moles of strontium bromide? Gram-Gram Conversions Use the equations from the seventh page of this packet to answer the following questions. 4. How many grams of pentane are required to make 16 grams of carbon dioxide? 5. How many grams of oxygen would be required to react with exactly 5.25 grams of propanone? 6. How many grams of water vapor can be produced by completely burning 25 grams of 2,3- dimethyloctane in oxygen? Limiting Reactants Use the equations from the seventh page of this packet to answer the following questions. 7. If 5.00 grams of oxygen react with 5.00 grams of ethanal, which reactant is the limiting reactant? 8. If 3.69 grams of 2-hexene react with 4.86 grams of oxygen, which reactant is the limiting reactant?
AP Chemistry Hints for synthesis, decomposition, and combustion reactions: For synthesis reactions, two or more substances will come together to make one product. For example: iron and oxygen Iron and oxygen would come together to form iron oxide. Oxygen is one of the seven diatomic elements (O2). Iron has two different possible ions Fe 2+ and Fe 3+. Since iron has two different possible ions on the ion page, the question is whether it would combine with oxygen to form iron (II) oxide or iron (III) oxide. Either would be correct. There is more than one correct answer to this problem. The oxide ion is O 2-. When the oxide ion combines with Fe 2+, a 2+ charge cancels with the 2- charge and so only one of each are required. When the oxide ion combines with Fe 3+ though, a 3+ charge does not cancel a 2- charge. A common denominator must be found. The common denominator between 2 and 3 would be six. If you have 2 Fe 3+ ions and 3 O 2- ions, then a total positive charge of six will cancel with a total negative charge of six. So, 2 iron (III) ions would be required for every 3 oxide ions. If the iron (II) ion is used: iron + oxygen iron (II) oxide Fe + O2 FeO And then that would balance to: 2Fe + O2 2FeO If the iron (III) ion is used: Iron + oxygen iron (III) oxide Fe + O2 Fe2O3 And then that would balance to: 4Fe + 3O2 2Fe2O3 For a synthesis reaction combining two compounds, just add everything together and check to see that it makes sense. Calcium oxide would be CaO since Ca is a 2+ charge and oxide has a 2- charge. Sulfur dioxide is a molecular compound (not ionic). The di- prefix tells us that there are two oxygen atoms. The lack of a prefix in front of sulfur indicates that there is only one sulfur atom. So, the formula for sulfur dioxide is SO2. Calcium oxide and sulfur dioxide CaO + SO2 CaSO3 Does this make sense? Calcium is a 2+ ion. SO3 2- is the sulfite ion. A 2+ charge will cancel with a 2- charge and so yes only one calcium ion would be required per sulfate ion. Calcium sulfite is the most likely product.
For decomposition reactions, follow these general guidelines: - A compound containing only two elements will decompose into those two separate elements. - A metal carbonate (like CaCO3) will decompose to lose carbon dioxide (CO2) as one product so only the metal oxide (CaO) will remain as the other product. - A metal hydroxide [Ca(OH)2] will decompose to lose water (H2O) as one product so only the metal oxide (CaO) will remain as the other product. - A metal chlorate (KClO3) will decompose to lose oxygen (O2) as one product so only the metal chloride remains (KCl) as the other product. - Acids (H2SO4) will decompose to form water (H2O) and what ever else is left remaining (SO3). For the organic compounds in the combustion reactions: - Alkanes have only single bonds. - Alkenes will contain a double bond. A number must indicate where the double bond is located (on which carbon the bond starts). - Alkynes will contain a triple bond. A number must indicate where the triple bond is located (on which carbon the bond starts). - Any substituent groups (methyl, ethyl, etc.) coming off of the main carbon chain must also be identified by a number representing the carbon to which they are attached. - Alcohols will contain an OH functional group. - Aldehydes will contain a CHO functional group. - Ketones will contain a CO functional group. - Carboxylic acids will contain a COOH functional group. Meth means one Eth means two Prop means three But means four Pent means five Hex means six Hept means seven Oct means eight Non means nine Dec means ten
Stoichiometry Review Step 1: The first step in stoichiometry is to make sure that you have a balanced chemical equation first. For example: 4Fe + 3O2 2Fe2O3 Step 2: For mole-to-mole conversions, use mole ratios. For example: How many moles of Fe2O3 are produced from 7.50 moles of Fe? Solution: 7.50 moles Fe x 2 moles Fe2O3 = 3.75 moles of Fe2O3 4 moles Fe For gram-to-gram conversions, use mole ratios and the molar mass of each substance. For example: How many grams of oxygen are required to produce 16.89 grams of Fe2O3? Solution: The molar mass of Fe2O3 is159.7 g/mol and the molar mass of O2 is 32.0 g/mol. 16.89 g Fe2O3 x 1mole Fe2O3 x 3 moles O2 x 32.0 g O2 = 5.077 grams O2 159.7 g Fe2O3 2 moles Fe2O3 1 mole O2 For limiting reactant problems, perform a gram-to-gram conversion for both reactants separately to determine which would limit the reaction. In other words, which would make less product. For example: How many grams of Fe2O3 could be made by combining 10.0 grams of iron with 10.0 grams of oxygen? Solution: 10.0 g Fe x 1 mole Fe x 2 mol Fe2O3 x 159.7 g Fe2O3 = 14.3 g Fe2O3 Iron would be the limiting 55.85 g Fe 4 mol Fe 1 mol Fe2O3 reactant. 14.3 g is less than 33.3 g. 10.0 g O2 x 1 mol O2 x 2 mol Fe2O3 x 159.7 g Fe2O3 = 33.3 g Fe2O3 32.0 g O2 3 mol O2 1 mol Fe2O3