2-2 Homework Module Two PDF

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2-2 Homework Module Two Chapter 3 45, Write the chemical formula for each of the following compounds. List the symbols for the elements in the order that the elements are mentioned in the description. a. A compound with molecules that consist of two phosphorus atoms and five oxygen atoms. a. P2O5 Diphosphorus pentoxide b. A compound with molecules that consist of two hydrogen atoms and one sulfur atom. a. H2S Hydrogen sulfide c. A compound that contains three calcium atoms for every two nitrogen atoms. a. Ca3N2 Calcium nitride d. A compound with molecules that consist of 12 carbon atoms, 22 hydrogen atoms, and 11 oxygen atoms. a. C12H22O11 Sucrose 55, Classify each of the following as either a molecular compound or an ionic compound. a. cadmium fluoride, CdF2 (a starting material for lasers) a. Cadmium fluoride is an ionic compound due to the charges. (Cadmium +2, Fluorine -1) b. sulfur dioxide, SO2 (a food additive that inhibits browning and bacterial growth) a. Sulfur dioxide is a molecular compound since both elements are nonmetals. 71 Compare and contrast the information given in the Lewis structure, the space-filling model, the ball-and-stick model, and the geometric sketch of an ammonia molecule, NH3. All three models show the arrangement of the NH3 molecule. The space-filled model shows the electron charge clouds for each atom. The ball-and-stick shows the molecules correct molecular shape identifying the covalent bonds, while the geometric sketch shows the angle at which each atom is located. This shows how the electrons repel one another. 73, What are the particles that form the basic structure of water? Describe the attraction that holds these particles together. Draw a rough sketch that shows the attraction between two water molecules. Oxygen atoms attract electrons more than a hydrogen atom does. This leads to a large partial minus charge on the oxygen atom (represented by a δ−) and a large partial plus charge on the hydrogen atom (represented by a δ+). 81, Write the name for each of the following chemical formulas. a. ClO2 (a commercial bleaching agent)

b. c. d. e.

a. Chlorine Dioxide C2H6 (in natural gas) a. Ethane HI (when dissolved in water, used to make pharmaceuticals) a. Hydrogen iodide P3N5 (for doping semiconductors) a. Triphosphorus pentanitride BrCl (an industrial disinfectant) a. Bromine chloride

83, Write the chemical formula for each of the following names. a. ammonia (a household cleaner when dissolved in water) a. NH3 b. tetraphosphorus hexasulfide (used in organic chemical reactions) a. P4S6 c. iodine monochloride (used for organic synthesis) a. ICl d. hydrogen chloride (used to make hydrochloric acid) a. HCl 97, Write the name for each of these chemical formulas. a. CdI2 (a nematocide—that is, it kills certain parasitic worms.) a. Cadmium iodide b. Ca3P2 (in signal flares) a. Calcium phosphide c. Au(OH)3 (used in gold plating) a. gold trihydroxide d. FeCl2 (in pharmaceutical preparations) a. ferrous chloride e. NH4HSO4 (in hair wave formulations) a. ammonium hydrogen sulfate 99, Write chemical formulas for each of the following names. a. barium chloride (used in manufacture of white leather) a. BaCl2 b. cobalt(III) oxide (used in coloring enamels) a. Co2O3 c. manganese(II) chloride (used in pharmaceutical preparations) a. MnCl2 d. iron(III) acetate (a medicine)

a. C14H27Fe3O18 e. chromium(III) phosphate (in paint pigments) a. CrPO₄ f. magnesium hydrogen phosphate (a laxative) a. HMgO4P Chapter 8 59, Complete the following calculations and report your answers with the correct number of significant figures. The exponential factors, such as 103, are exact, and the 5280 in part (c) is exact. All the other numbers are not exact. a. 8.9932 × 10^−2 (103) 0.0048/ (10^−6)7.140 = 6.0458487395 × 104 b. (44.945 − 23.775) (103)3.785412/ (15.200) (453.59237) = 2.3914216968 × 106 c. 456.8(5280)2/ (103)2(1.609)2 = 3.296901928 × 104 67, The density of whole blood is 1.05 g/mL. A typical adult has about 5.5 L of whole blood. What is the mass in pounds of this amount of whole blood? 5.5 converted to ml is 5500. Multiply by 1.05 g/ml equals 5775 grams. Convert that to pounds. 12.7317 pounds. 108, Absolute zero, the lowest possible temperature, is exactly 0 K. What is this temperature in °C?…in °F? In C°, 0K is -273.15. In F°, it is -459.67. Chapter 9 30, A multivitamin tablet contains 40 milligrams of potassium. How many moles of potassium does each tablet contain? Each tablet contains 1.6 moles of potassium. 32, A multivitamin tablet contains 1.93 × 10−6 mole of chromium. How many micrograms of chromium does each tablet contain? 1.93 x 10-6x 51.9961 = .00100352473g x 1000000 mcg= 1003.542 mcg 45, Many famous “rubies” are in fact spinels, which look like rubies but are far less valuable. Spinels consist primarily of MgAl2O4, whereas rubies are primarily Al2O3. If the Timur Ruby, a 361-carat spinel, were pure MgAl2O4, how many moles of MgAl2O4 would it contain? (There are exactly 5 carats per gram.)

361carats / 5 carats/g = 72.2 g(24.305)+(2 x 26.981539)+(4 x 15.9994) = 142.244078 g/mol72.2 g/ 142.244078 = .508 mol 49, Calcium phosphide is used to make fireworks. Write a conversion factor that converts between moles of calcium ions in calcium phosphide, Ca3P2, and moles of Ca3P2. 3 mol Ca/ 1 mol Ca3P2 57, Manganese metal is produced from the manganese(III) oxide, Mn2O3,which is found in manganite, a manganese ore. The manganese is reduced from its +3 oxidation state in Mn2O3 to the zero oxidation state of the uncharged metal by reacting the Mn2O3 with a reducing agent such as aluminum or carbon. How many pounds of manganese are in 1.261 tons of Mn2O3? (1 ton = 2000 pounds) (54.938045 x 2)+(15.994 x 3) = 157.85809 g/mol2522 lb x 54.938045 g/mol/157.85809 g/mol = 877.71 pounds 72, About 40 different substances called organophosphorus compounds are registered in the United States as insecticides. They are considered less damaging to the environment than some other insecticides because they breakdown relatively rapidly in the environment. The first of these organophosphorus insecticides to be produced was tetraethyl pyrophosphate, TEPP, which is 33.11% carbon, 6.95% hydrogen, 38.59% oxygen, and 21.35% phosphorus. It has a molecular mass of 290.190. What is the molecular formula for TEPP? C8H20O7P2 Chapter 10 43, Uranium is distributed in a form called yellow cake, which is made from uranium ore. In the second step of the reactions that form yellow cake from uranium ore, uranyl sulfate, UO2SO4, is converted to (NH4)2U2O7. 2UO2SO4 + 6NH3 + 3H2O → (NH4)2U2O7 + 2(NH4)2SO4 a. What is the maximum mass, in kilograms, of (NH4)2U2O7 that can be formed from the reaction of 100 kg of water and 100 kg of ammonia with 481 kg of UO2SO4? a. 410.0159622 kg b. Explain why two of these substances are in excess and one is limiting. a. H2O and NH4 are in excess because the amount available to complete the reaction is in abundance. The third substance is limiting because there is only a limited supply of it to fuel the reaction. 61, Consider the neutralization reaction that takes place when hydrochloric acid reacts with solid nickel (II) carbonate. a. Write a conversion factor that relates moles of HCl to moles of NiCO3 for this reaction.

a. The conversion factor that can be used to calculate the moles of NiCO3 from moles HCl is 1 mole NiCO3/ 2 mole HCl. b. What is the minimum volume of 6.0 M HCl necessary to react completely with 14.266 g of solid nickel (II) carbonate, NiCO3? a. The volume of HCl needed is 40. mL...