Problem 1PS Problem 2PS: Define mass number. What is the difference between mass number and atomic mass? Problem 3PS: An atom has a very small nucleus surrounded by an electron cloud. Figure 2.1 represents the nucleus... Problem 4PS: A gold atom has a radius of 145 pm. If you could string gold atoms like beads on a thread, how many... Problem 5PS: Give the complete symbol(ZAX), including atomic number and mass number, for each of the following... Problem 6PS: Give the complete symbol(ZAX), including atomic number and mass number, of (a) a nickel atom with 31... Problem 7PS Problem 8PS: Atomic structure. (a) The synthetic radioactive element technetium is used in many medical studies.... Problem 9PS Problem 10PS: In 1886 Eugene Goldstein observed positively charged particles moving in the opposite direction to... Problem 11PS: Marie Curie was born in Poland but studied and carried out her research in Paris. In 1903, she... Problem 12PS Problem 13PS: The mass of an 16 O atom is 15.995 u. What is its mass relative to the mass of an atom of 12C? Problem 14PS: What is the mass of one 16O atom, in grams? (The mass of an 16O atom is 15.995 u.) Problem 15PS: Cobalt has three radioactive isotopes used in medical studies. Atoms of these isotopes have 30, 31,... Problem 16PS: Naturally occurring silver exists as two isotopes having mass numbers 107 and 109. How many protons,... Problem 17PS: Name and describe the composition of the three hydrogen isotopes. Problem 18PS: Which of the following are isotopes of element X, the atomic number for which is 9: 919X, 920X,... Problem 19PS: Thallium has two stable isotopes, 203TIand 205Tl. Knowing that the atomic weight of thallium is... Problem 20PS: Strontium has four stable isotopes. Strontium-84 has a very low natural abundance, but 86Sr, 87Sr,... Problem 21PS: Verify that the atomic weight of lithium is 6.94, given the following information: 6Li, mass =... Problem 22PS: Verify that the atomic weight of magnesium is 24.31, given the following information: 24Mg, mass =... Problem 23PS: Gallium has two naturally occurring isotopes, 69Ga and 71Ga, with masses of 68.9257 u and 70.9249 u,... Problem 24PS: Europium has two stable isotopes, 151Eu and 153Eu, with masses of 150.9197 u and 152.9212 u,... Problem 25PS: Titanium and thallium have symbols that are easily confused with each other. Give the symbol, atomic... Problem 26PS: In Groups 4A-6A, there are several elements whose symbols begin with S. Name these elements, and for... Problem 27PS: How many periods of the periodic table have 8 elements, how many have 18 elements, and how many have... Problem 28PS Problem 29PS Problem 30PS Problem 31PS: Classify the following elements as metals, metalloids, or nonmetals: N, Na, Ni, Ne, and Np. Problem 32PS Problem 33PS Problem 34PS Problem 35PS: What is the charge on the common monatomic ions of the following elements? (a) magnesium (b) zinc... Problem 36PS: What is the charge on the common monatomic ions of the following elements? (a) selenium (b) fluorine... Problem 37PS Problem 38PS Problem 39PS: When a potassium atom becomes a monatomic ion, how many electrons does it lose or gain? What noble... Problem 40PS: When oxygen and sulfur atoms become monatomic ions, how many electrons does each lose or gain? Which... Problem 41PS Problem 42PS Problem 43PS: Give the formula and the number of each ion that makes up each of the following compounds: (a) K2S... Problem 44PS: Give the formula and the number of each ion that makes up each of the following compounds: (a)... Problem 45PS Problem 46PS Problem 47PS Problem 48PS Problem 49PS Problem 50PS Problem 51PS Problem 52PS Problem 53PS: Write the formulas for the four ionic compounds that can be made by combining each of the cations... Problem 54PS: Write the formulas for the four ionic compounds that can be made by combining the cations Mg2+ and... Problem 55PS: Sodium ions, Na+, form ionic compounds with fluoride ions, F, and iodide ions, I. The radii of these... Problem 56PS: Consider the two ionic compounds NaCl and CaO. In which compound are the cation-anion attractive... Problem 57PS Problem 58PS: Name each of the following binary, nonionic compounds: (a) N2O5 (b) P4S3 (c) OF2 (d) XeF4 Problem 59PS Problem 60PS Problem 61PS: Calculate the mass, in grams, of each the following: (a) 2.5 mol of aluminum (b) 1.25 103 mol of... Problem 62PS: Calculate the mass, in grams, of each the following: (a) 4.24 mol of gold (b) 15.6 mol of He (c)... Problem 63PS: Calculate the amount (moles) represented by each of the following: (a) 127.08 g of Cu (b) 0.012 g of... Problem 64PS: Calculate the amount (moles) represented by each of the following: (a) 16.0 g of Na (b) 0.876 g of... Problem 65PS: You are given 1.0-g samples of He, Fe, Li, Si, and C. Which sample contains the largest number of... Problem 66PS: You are given 0.10-g samples of K, Mo, Cr, and Al. List the samples in order of the amount (moles),... Problem 67PS: Analysis of a 10.0-g sample of apatite (a major component of tooth enamel) showed that it was made... Problem 68PS: A semiconducting material is composed of 52 g of Ga, 9.5 g of Al, and 112 g of As. Which element has... Problem 69PS: Calculate the molar mass of each of the following compounds: (a) Fe2O3, iron(III) oxide (b) BCI3,... Problem 70PS: Calculate the molar mass of each of the following compounds: (a) Fe(C6H11O7)2, iron(II) gluconate, a... Problem 71PS: Calculate the molar mass of each hydrated compound. Note that the water of hydration is included in... Problem 72PS Problem 73PS: What mass is represented by 0.0255 mol of each of the following compounds? (a) C3H7OH, 2-propanol,... Problem 74PS: Assume you have 0.123 mol of each of the following compounds. What mass of each is present? (a)... Problem 75PS: Sulfur trioxide, SO3, is made industrially in enormous quantities by combining oxygen and sulfur... Problem 76PS: How many ammonium ions and how many sulfate ions are present in a 0.20 mol sample of (NH4)2SO4? How... Problem 77PS: Acetaminophen, whose structure is drawn below, is the active ingredient in some nonprescription pain... Problem 78PS: An Alka-Seltzer tablet contains 324 mg of aspirin (C.9H8O4,), 1904 mg of NaHCO3, and 1000. mg of... Problem 79PS: Calculate the mass percent of each element in the following compounds: (a) PbS, lead(I1) sulfide,... Problem 80PS: Calculate the mass percent of each element in the following compounds: (a) C8H10N2O2, caffeine (b)... Problem 81PS: Calculate the mass percent of copper in CuS, copper(II) sulfide. If you wish to obtain 10.0 g of... Problem 82PS: Calculate the mass percent of titanium in the mineral ilmenite, FeTiO3. What mass of ilmenite (in... Problem 83PS: Succinic acid occurs in fungi and lichens. Its empirical formula isC2H3O2, and its molar mass is... Problem 84PS: An organic compound has the empirical formula C2H4NO. If its molar mass is 116.1 g/mol, what is the... Problem 85PS Problem 86PS: Complete the following table: Problem 87PS: Acetylene is a colorless gas used as a fuel in welding torches, among other things. It is 92.26% C... Problem 88PS: A large family of boron-hydrogen compounds has the general formula BxHy. One member of this family... Problem 89PS: Cumene, a hydrocarbon, is a compound composed only of C and H. It is 89.94% carbon, and its molar... Problem 90PS: In 2006, a Russian team discovered an interesting molecule they called sulflower because of its... Problem 91PS: Mandelic acid is an organic acid composed of carbon (63.15%), hydrogen (5.30%), and oxygen (31.55%).... Problem 92PS: Nicotine, a poisonous compound found in tobacco leaves, is 74.0% C, 8.65% H, and 17.35% N. Its molar... Problem 93PS: A compound containing xenon and fluorine was prepared by shining sunlight on a mixture of Xe (0.526... Problem 94PS: Elemental sulfur (1.256 g) is combined with fluorine, to give a compound with the formula SFx, a... Problem 95PS: Epsom salt is used in tanning leather and in medicine. It is hydrated magnesium sulfate, MgSO4 7... Problem 96PS: You combine 1.25 g of germanium, Ge, with excess chlorine, Cl2. The mass of product, GexCly, is 3.69... Problem 97PS: The mass spectrum of nitrogen dioxide is illustrated here. (a) Identify the cations present for each... Problem 98PS: The mass spectrum of phosphoryl chloride. POF3, is illustrated here. (a) Identify the cation... Problem 99PS: The mass spectrum of CH3Cl is illustrated here. You know that carbon has two stable isotopes, and... Problem 100PS Problem 101GQ: Fill in the blanks in the table (one column per element). Problem 102GQ: Potassium has three naturally occurring isotopes (39K, 40K, and 41K), but 40K has a very low natural... Problem 103GQ: Crossword Puzzle: In the 2 2 box shown here, each answer must be correct four ways: horizontally,... Problem 104GQ: The following chart shows a general decline in abundance with increasing mass among the first 30... Problem 105GQ: Copper atoms. (a) What is the average mass of one copper atom? (b) Students in a college computer... Problem 106GQ Problem 107GQ Problem 108GQ: Identify two nonmetallic elements that have allotropes and describe the allotropes of each. Problem 109GQ Problem 110GQ Problem 111GQ Problem 112GQ: When a sample of phosphorus burns in air, the compound P4O10 forms. One experiment showed that 0.744... Problem 113GQ: Although carbon-12 is now used as the standard for atomic weights, this has not always been the case... Problem 114GQ: A reagent occasionally used in chemical synthesis is sodium-potassium alloy. (Alloys are mixtures of... Problem 115GQ Problem 116GQ Problem 117GQ: Which of the following compounds has the highest mass percent of chlorine? (a) BCl3 (b) AsCl3 (c)... Problem 118GQ: Which of the following samples has the largest number of ions? (a) 1.0 g of BeCl2 (b) 1.0 g of MgCl2... Problem 119GQ: The structure of one of the bases in DNA, adenine, is shown here. Which represents the greater mass:... Problem 120GQ Problem 121GQ: A drop of water has a volume of about 0.050 mL. How many molecules of water are in a drop of water?... Problem 122GQ: Capsaicin, the compound that gives the hot taste to chili peppers, has the formula C18H27NO3. (a)... Problem 123GQ Problem 124GQ: Write the molecular formula and calculate the molar mass for each of the molecules shown here. Which... Problem 125GQ: Malic acid, an organic acid found in apples, contains C, H, and O in the following ratios:... Problem 126GQ: Your doctor has diagnosed you as being anemicthat is, as having too little iron in your blood. At... Problem 127GQ: A compound composed of iron and carbon monoxide, Fex(CO)y, is 30.70% iron. What is the empirical... Problem 128GQ: Ma huang, an extract from the ephedra species of plants, contains ephedrine. The Chinese have used... Problem 129GQ: Saccharin, a molecular model of which is shown below, is more than 300 times sweeter than sugar. It... Problem 130GQ Problem 131GQ: Write the formula for each of the following pounds and indicate which ones are best described as... Problem 132GQ: Complete the table by placing symbols, formulas, and names in the blanks. Problem 133GQ: Empirical and molecular formulas. (a) Fluorocarbonyl hypofluorite is composed of 14.6% C, 30.0% O,... Problem 134GQ: Cacodyl, a compound containing arsenic, was reported in 1842 by the German chemist Robert Wilhelm... Problem 135GQ: The action of bacteria on meat and fish produces a compound called cadaverine. As its name and... Problem 136GQ: In the laboratory you combine 0.125 g of nickel with CO and isolate 0.364 g of Ni(CO)x. What is the... Problem 137GQ: A compound called MMT was once used to boost the octane rating of gasoline. What is the empirical... Problem 138GQ: Elemental phosphorus is made by heating calcium phosphate with carbon and sand in an electric... Problem 139GQ: Chromium is obtained by heating chromium(III) oxide with carbon. Calculate the mass percent of... Problem 140GQ: Stibnite, Sb2S3, is a dark gray mineral from which antimony metal is obtained. What is the mass... Problem 141GQ: Direct reaction of iodine (I2) and chlorine (Cl2) produces an iodine chloride, IxCly, a bright... Problem 142GQ: In a reaction, 2.04 g of vanadium combined with 1.93 g of sulfur to give a pure compound. What is... Problem 143GQ: Iron pyrite, often called fools gold, has the formula FeS2. If you could convert 15.8 kg of iron... Problem 144GQ: Which of the following statements about 57.1 g of octane, C8H18 is (are) not true? (a) 57.1 g is... Problem 145GQ: The formula of barium molybdate is BaMoO4. Which of the following is the formula of sodium... Problem 146GQ: A metal M forms a compound with the formula MCl4. If the compound is 74.75% chlorine, what is the... Problem 147GQ: Pepto-Bismol, which can help provide relief for an upset stomach, contains 300. mg of bismuth... Problem 148GQ: The weight percent of oxygen in an oxide that has the formula MO2 is 15.2%. What is the molar mass... Problem 149GQ: The mass of 2.50 mol of a compound with the formula ECl4, in which E is a nonmetallic element, is... Problem 150GQ: The elements A and Z combine to produce two different compounds: A2Z3 and AZ2. If 0.15 mol of A2Z3... Problem 151GQ: Polystyrene can be prepared by heating styrene with tribromobenzoyl peroxide in the absence of air.... Problem 152GQ: A sample of hemoglobin is found to be 0.335% iron. What is the molar mass of hemoglobin if there are... Problem 153GQ: Consider an atom of 64Zn. (a) Calculate the density of the nucleus in grams per cubic centimeter,... Problem 154GQ: Estimating the radius of a lead atom. (a) You are given a cube of lead that is 1.000 cm on each... Problem 155GQ: A piece of nickel foil, 0.550 mm thick and 1.25 cm square, is allowed to react with fluorine, F2, to... Problem 156GQ: Uranium is used as a fuel, primarily in the form of uranium(IV) oxide, in nuclear power plants. This... Problem 157GQ: In an experiment, you need 0.125 mol of sodium metal. Sodium can be cut easily with a knife (Figure... Problem 158GQ: Mass spectrometric analysis showed that there are four isotopes of an unknown element having the... Problem 159IL: If Epsom salt, MgSO4 x H2O, is heated to 250 C, all the water of hydration is lost. On heating a... Problem 160IL: The alum used in cooking is potassium aluminum sulfate hydrate, KAl(SO4)2 x H2O. To find the value... Problem 161IL: Tin metal (Sn) and purple iodine (I2) combine to form orange, solid tin iodide with an unknown... Problem 162IL: When analyzed, an unknown compound gave these experimental results: C, 54.0%; h, 6.00%; and O,... Problem 163IL: Two general chemistry students working together in the lab weigh out 0.832 g of CaCl2 2 H2O into a... Problem 164IL: To find the empirical formula of tin oxide, you first react tin metal with nitric acid in a... Problem 165SCQ Problem 166SCQ Problem 167SCQ: The photo here depicts what happens when a coil of magnesium ribbon and a few calcium chips are... Problem 168SCQ: A jar contains some number of jelly beans. To find out precisely how many are in the jar, you could... format_list_bulleted