Problem 3.1QP: What is an atomic mass unit? Why is it necessary to introduce such a unit? Problem 3.2QP: What is the mass (in amu) of a carbon-12 atom? Why is the atomic mass of carbon listed as 12.01 amu... Problem 3.3QP: Explain clearly what is meant by the statement, The atomic mass of gold is 197.0 amu. Problem 3.4QP: What information would you need to calculate the average atomic mass of an element? Problem 3.5QP: The atomic masses of 1735Cl (75.53 percent) 1737Cl and (24.47 percent) are 34.968 amu and 36.956... Problem 3.6QP: The atomic masses of 36Li and 37Li are 6.0151 amu and 7.0160 amu, respectively. Calculate the... Problem 3.7QP: What is the mass in grams of 13.2 amu? Problem 3.8QP: How many amu are there in 8.4 g? Problem 3.9QP: Define the term mole. What is the unit for mole in calculations? What does the mole have in common... Problem 3.10QP: What is the molar mass of an atom? What are the commonly used units for molar mass? Problem 3.11QP: Earths population is about 7.2 billion. Suppose that every person on Earth participates in a process... Problem 3.12QP: The thickness of a piece of paper is 0.0036 in. Suppose a certain book has an Avogadros number of... Problem 3.13QP: How many atoms are there in 5.10 moles of sulfur (S)? Problem 3.14QP: How many moles of cobalt (Co) atoms are there in 6.00 109 (6 billion) Co atoms? Problem 3.15QP: How many moles of calcium (Ca) atoms are in 77.4 g of Ca? Problem 3.16QP: How many grams of gold (Au) are there in 15.3 moles of Au? Problem 3.17QP: What is the mass in grams of a single atom of each of the following elements? (a) Hg, (b) Ne. Problem 3.18QP: What is the mass in grams of a single atom of each of the following elements? (a) As, (b) Ni. Problem 3.19QP: What is the mass in grams of 1.00 1012 lead (Pb) atoms? Problem 3.20QP: A modern penny weighs 2.5 g but contains only 0.063 g of copper (Cu). How many copper atoms are... Problem 3.21QP: Which of the following has more atoms: 1.10 g of hydrogen atoms or 14.7 g of chromium atoms? Problem 3.22QP: Which of the following has a greater mass: 2 atoms of lead or 5.1 1023 mole of helium. Problem 3.23QP: Calculate the molecular mass or formula mass (in amu) of each of the following substances: (a) CH4,... Problem 3.24QP: Calculate the molar mass of the following substances: (a) Li2CO3, (b) CS2, (c) CHCl3 (chloroform),... Problem 3.25QP: Calculate the molar mass of a compound if 0.372 mole of it has a mass of 152 g. Problem 3.26QP: How many molecules of ethane (C2H6) are present in 0.334 g of C2H6? Problem 3.27QP: Calculate the number of C, H, and O atoms in 1.50 g of glucose (C6H12O6), a sugar. Problem 3.28QP: Dimethyl sulfoxide [(CH3)2SO], also called DMSO, is an important solvent that penetrates the skin,... Problem 3.29QP: Pheromones are a special type of compound secreted by the females of many insect species to attract... Problem 3.30QP: The density of water is 1.00 g/mL at 4C. How many water molecules are present in 2.56 mL of water at... Problem 3.31QP: Describe the operation of a mass spectrometer. Problem 3.32QP: Describe how you would determine the isotopic abundance of an element from its mass spectrum. Problem 3.33QP: Carbon has two stable isotopes, 612C and 613C, and fluorine has only one stable isotope, 919F. How... Problem 3.34QP: Hydrogen has two stable isotopes, 11H and 12H, and sulfur has four stable isotopes, 1632S, 1633S,... Problem 3.35QP: Use ammonia (NH3) to explain what is meant by the percent composition by mass of a compound. Problem 3.36QP: Describe how the knowledge of the percent composition by mass of an unknown compound can help us... Problem 3.37QP: Tin (Sn) exists in Earths crust as SnO2. Calculate the percent composition by mass of Sn and O in... Problem 3.38QP: For many years chloroform (CHCl3) was used as an inhalation anesthetic in spite of the fact that it... Problem 3.39QP: Cinnamic alcohol is used mainly in perfumery, particularly in soaps and cosmetics. Its molecular... Problem 3.40QP: All of the substances listed here are fertilizers that contribute nitrogen to the soil. Which of... Problem 3.41QP: The formula for rust can be represented by Fe2O3. How many moles of Fe are present in 24.6 g of the... Problem 3.42QP: Tin(II) fluoride (SnF2) is often added to toothpaste as an ingredient to prevent tooth decay. What... Problem 3.43QP: What are the empirical formulas of the compounds with the following compositions? (a) 2.1 percent H,... Problem 3.44QP: What are the empirical formulas of the compounds with the following compositions? (a) 40.1 percent... Problem 3.45QP: The anticaking agent added to Morton salt is calcium silicate, CaSiO3. This compound can absorb up... Problem 3.46QP: What does the word empirical in empirical formula mean? Problem 3.47QP: If we know the empirical formula of a compound, what additional information do we need to determine... Problem 3.48QP: The empirical formula of a compound is CH. If the molar mass of this compound is about 78 g, what is... Problem 3.49QP: The molar mass of caffeine is 194.19 g. Is the molecular formula of caffeine C4H5N2O or C8H10N4O2? Problem 3.50QP: Peroxyacylnitrate (PAN) is one of the components of smog. It is a compound of C, H, N, and O.... Problem 3.51QP: Allicin is the compound responsible for the characteristic smell of garlic. An analysis of the... Problem 3.52QP: Monosodium glutamate (MSG), a food-flavor enhancer, has been blamed for Chinese restaurant syndrome,... Problem 3.53QP: Use the formation of water from hydrogen and oxygen to explain the following terms: chemical... Problem 3.54QP: What is the difference between a chemical reaction and a chemical equation? Problem 3.55QP: Why must a chemical equation be balanced? What law is obeyed by a balanced chemical equation? Problem 3.56QP: Write the symbols used to represent gas, liquid, solid, and the aqueous phase in chemical equations. Problem 3.57QP: Problems 3.57Balance the following equations using the method outlined in Section 3.7. (a)C+O2CO... Problem 3.58QP: Balance the following equations using the method outlined in Section 3.7. (a) N2O5N2O4+O2 (b)... Problem 3.59QP Problem 3.60QP Problem 3.61QP Problem 3.62QP Problem 3.63QP: Consider the combustion of carbon monoxide (CO) in oxygen gas: 2CO(g)+O2(g)2CO2(g) Starting with... Problem 3.64QP: Silicon tetrachloride (SiCl4) can be prepared by heating Si in chlorine gas: Si(s)+2Cl2(g)SiCl4(l)... Problem 3.65QP: Ammonia is a principal nitrogen fertilizer. It is prepared by the reaction between hydrogen and... Problem 3.66QP: Certain race cars use methanol (CH3OH, also called wood alcohol) as a fuel. The combustion of... Problem 3.67QP: Calculate the mass in grams of iodine (I2) that will react completely with 20.4 g of aluminum (Al)... Problem 3.68QP: How many grams of sulfur (S) are needed to react completely with 246 g of mercury (Hg) to form HgS? Problem 3.69QP Problem 3.70QP: When baking soda (sodium bicarbonate or sodium hydrogen carbonate, NaHCO3) is heated, it releases... Problem 3.71QP: If chlorine bleach is mixed with other cleaning products containing ammonia, the toxic gas NCl3(g)... Problem 3.72QP: Fermentation is a complex chemical process of wine making in which glucose is converted into ethanol... Problem 3.73QP: Each copper(II) sulfate unit is associated with five water molecules in crystalline copper(II)... Problem 3.74QP: For many years the recovery of goldthat is, the separation of gold from other materialsinvolved the... Problem 3.75QP: Limestone (CaCO3) is decomposed by heating to quicklime (CaO) and carbon dioxide. Calculate how many... Problem 3.76QP: Nitrous oxide (N2O) is also called laughing gas. It can be prepared by the thermal decomposition of... Problem 3.77QP Problem 3.78QP: A common laboratory preparation of oxygen gas is the thermal decomposition of potassium chlorate... Problem 3.79QP Problem 3.80QP Problem 3.81QP: Consider the reaction 2A+BC (a)In the diagram here that represents the reaction, which reactant, A... Problem 3.82QP: Consider the reaction N2+3H22NH3 Assuming each model represents 1 mole of the substance, show the... Problem 3.83QP: Nitric oxide (NO) reacts with oxygen gas to form nitrogen dioxide (NO2), a dark-brown gas:... Problem 3.84QP: Ammonia and sulfuric acid react to form ammonium sulfate. (a) Write an equation for the reaction.... Problem 3.85QP: Propane (C3H8) is a component of natural gas and is used in domestic cooking and heating. (a)... Problem 3.86QP: Consider the reaction MnO2+4HClMnCl2+Cl2+2H2O If 0.86 mole of MnO2 and 48.2 g of HCl react, which... Problem 3.87QP: Why is the theoretical yield of a reaction determined only by the amount of the limiting reactant? Problem 3.88QP Problem 3.89QP: Hydrogen fluoride is used in the manufacture of Freons (which destroy ozone in the stratosphere) and... Problem 3.90QP: Nitroglycerin (C3H5N3O9) is a powerful explosive. Its decomposition may be represented by... Problem 3.91QP: Titanium(IV) oxide (TiO2) is a white substance produced by the action of sulfuric acid on the... Problem 3.92QP: Ethylene (C2H4), an important industrial organic chemical, can be prepared by heating hexane (C6H14)... Problem 3.93QP: When heated, lithium reacts with nitrogen to form lithium nitride: 6Li(s)+N2(g)2Li3N(s) What is the... Problem 3.94QP: Disulfide dichloride (S2Cl2) is used in the vulcanization of rubber, a process that prevents the... Problem 3.95QP Problem 3.96QP: Rubidium is used in atomic clocks and other precise electronic equipment. The average atomic mass of... Problem 3.97QP Problem 3.98QP Problem 3.99QP Problem 3.100QP: Write balanced equations for the following reactions described in words. (a)Pentane burns in oxygen... Problem 3.101QP: Industrially, nitric acid is produced by the Ostwald process represented by the following equations:... Problem 3.102QP: A sample of a compound of Cl and O reacts with an excess of H2 to give 0.233 g of HCl and 0.403 g of... Problem 3.103QP Problem 3.104QP: A 26.2-g sample of oxalic acid hydrate (H2C2O4 2H2O) is heated in an oven until all the water is... Problem 3.105QP Problem 3.106QP: How many moles of O are needed to combine with 0.212 mole of C to form (a) CO and (b) CO2? Problem 3.107QP Problem 3.108QP: The aluminum sulfate hydrate [Al2(SO4)3 xH2O] contains 8.10 percent Al by mass. Calculate xthat is,... Problem 3.109QP: The explosive nitroglycerin (C3H5N3O9) has also been used as a drug to treat heart patients to... Problem 3.110QP Problem 3.111QP Problem 3.112QP: A certain metal oxide has the formula MO, where M denotes the metal. A 39.46-g sample of the... Problem 3.113QP Problem 3.114QP: One of the reactions that occurs in a blast furnace, where iron ore is converted to cast iron, is... Problem 3.115QP Problem 3.116QP Problem 3.117QP Problem 3.118QP: Analysis of a metal chloride XCl3 shows that it contains 67.2 percent Cl by mass. Calculate the... Problem 3.119QP Problem 3.120QP: Myoglobin stores oxygen for metabolic processes in muscle. Chemical analysis shows that it contains... Problem 3.121QP: Calculate the number of cations and anions in each of the following compounds: (a) 0.764 g of CsI,... Problem 3.122QP Problem 3.123QP Problem 3.124QP Problem 3.125QP: Aspirin or acetyl salicylic acid is synthesized by reacting salicylic acid with acetic anhydride:... Problem 3.126QP: Calculate the percent composition by mass of all the elements in calcium phosphate [Ca3(PO4)2], a... Problem 3.127QP: Lysine, an essential amino acid in the human body, contains C, H, O, and N. In one experiment, the... Problem 3.128QP Problem 3.129QP Problem 3.130QP Problem 3.131QP Problem 3.132QP Problem 3.133QP Problem 3.134QP Problem 3.135QP Problem 3.136QP: Platinum forms two different compounds with chlorine. One contains 26.7 percent Cl by mass, and the... Problem 3.137QP Problem 3.138QP Problem 3.139QP Problem 3.140QP: A compound X contains 63.3 percent manganese (Mn) and 36.7 percent O by mass. When X is heated,... Problem 3.141QP Problem 3.142QP Problem 3.143QP Problem 3.144QP Problem 3.145QP: A mixture of CuSO4 5H2O and MgSO4 7H2O is heated until all the water is lost. If 5.020 g of the... Problem 3.146QP: When 0.273 g of Mg is heated strongly in a nitrogen (N2) atmosphere, a chemical reaction occurs. The... Problem 3.147QP: A mixture of methane (CH4) and ethane (C2H6) of mass 13.43 g is completely burned in oxygen. If the... Problem 3.148QP: Leaded gasoline contains an additive to prevent engine knocking. On analysis, the additive compound... Problem 3.149QP: Because of its detrimental effect on the environment, the lead compound described in Problem 3.148... Problem 3.150QP Problem 3.151QP: A certain sample of coal contains 1.6 percent sulfur by mass. When the coal is burned, the sulfur is... Problem 3.152QP: Air is a mixture of many gases. However, in calculating its molar mass we need consider only the... Problem 3.153QP Problem 3.155QP: Octane (C8H18) is a component of gasoline. Complete combustion of octane yields H2O and CO2.... Problem 3.156QP: Industrially, hydrogen gas can be prepared by reacting propane gas (C3H8) with steam at about 400C.... Problem 3.157QP Problem 3.158QP Problem 3.160QP: Potash is any potassium mineral that is used for its potassium content. Most of the potash produced... Problem 3.161QP Problem 3.162QP: A certain metal M forms a bromide containing 53.79 percent Br by mass. What is the chemical formula... Problem 3.163QP Problem 3.165QP Problem 3.166QP: Interpreting, Modeling Estimating 3.166While most isotopes of light elements such as oxygen and... Problem 3.167QP: Without doing any detailed calculations, arrange the following substances in the increasing order of... Problem 3.169QP: Consider the reaction 6Li(s)+N2(g)2Li3N(s) Without doing any detailed calculations, choose one of... Problem 3.170QP: Estimate how high in miles you can stack up an Avogadros number of oranges covering the entire... Problem 3.171QP: The following is a crude but effective method for estimating the order of magnitude of Avogadros... format_list_bulleted