Question: If a solid block of glass, with

> True or false? Coefficients can be fractions when balancing a chemical equation. Whether true or false, explain why this can or cannot occur.

> a. Give two examples each of a single-displacement reaction and of a double-replacement reaction. How are the two reaction types similar, and how are they different? b. Give two examples each of a reaction in which formation of water is the driving forc

> Balance each of the following oxidation–reduction chemical reactions. a. P4(s) + O2(g) P4O10(s) b. MgO(s) + C(s) Mg(s) + CO(g) c. Sr(s) + H2O(l) Sr(OH)2(aq) + H2(g) d. Co(s) + HCl(aq)

> Balance each of the following oxidation–reduction reactions. a. Co(s) + Br2(l) CoBr3(s) b. Al(s) + H2SO4(aq) Al2(SO4)3(aq) + H2(g) c. Na(s) + H2O(l) NaOH(aq) + H2(g) d. Cu(s) + O2

> What do we mean when we say that the transfer of electrons can be the “driving force” for a reaction? Give an example of a reaction where this happens.

> Complete the following acid–base reactions by indicating the acid and base that must have reacted in each case to produce the indicated salt. a. + K2SO4(aq) + 2H2O(l) b. +

> What salt would form when each of the following strong acid/ strong base reactions takes place? a. HCl(aq) + KOH(aq) b. RbOH(aq) + HNO3(aq) c. HClO4(aq) + NaOH(aq) d. HBr(aq) + CsOH(aq)

> Balance each of the following chemical equations. a. Ba(NO3)2(aq) + Na2CrO4(aq) BaCrO4(s) + NaNO3(aq) b. PbCl2(aq) + K2SO4(aq) PbSO4(s) + KCl(aq) c. C2H5OH(l) + O2 (g) CO2 (g) + H2O(l) d. CaC2

> Describe briefly what happens when an ionic substance is dissolved in water.

> Balance each of the following chemical equations. a. KO2(s) + H2O(l) KOH(aq) + O2 (g) + H2O2 (aq) b. Fe2O3(s) + HNO3(aq) Fe(NO3)3(aq) + H2O(l) c. NH3(g) + O2 (g) NO(g) + H2O(g) d. PCl5(l) + H2

> Balance each of the following chemical equations. a. NaCl(s) + SO2(g) + H2O(g) + O2 (g) Na2SO4(s) + HCl(g) b. Br2 (l) + I2 (s) IBr3(s) c. Ca3N2 (s) + H2O(l) Ca(OH) 2 (aq) + PH3(g) d. BF3(

> Balance each of the following chemical equations. a. Fe3O4(s) + H2(g) Fe(l) + H2O(g) b. K2SO4(aq) + BaCl2(aq) BaSO4(s) + KCl(aq) c. HCl(aq) + FeS(s) FeCl2(aq) +

> Balance each of the following chemical equations. a. Na2SO4(aq) + CaCl2(aq) CaSO4(s) + NaCl(aq) b. Fe(s) + H2O(g) Fe3O4(s) + H2(g) c. Ca(OH)2(aq) + HCl(aq) CaCl2(aq) + H2O(l)

> Balance each of the following chemical equations. a. K2SO4(aq) + BaCl2(aq) BaSO4(s) + KCl(aq) b. Fe(s) + H2O(g) FeO(s) + H2(g) c. NaOH(aq) + HClO4(aq) NaClO4(aq) + H2O(l) d. Mg(

> Balance each of the following chemical equations. a. FeCl3(aq) + KOH(aq) Fe(OH)3(s) + KCl(aq) b. Pb(C2H3O2)2(aq) + KI(aq) PbI2(s) + KC2H3O2(aq) c. P4O10(s) + H2O(l) H3PO4 (aq) d. Li2O

> Balance each of the following equations that describe precipitation reactions. a. CaCl2(aq) + AgNO3(aq) Ca(NO3)2(aq) + AgCl(s) b. AgNO3(aq) + K2CrO4(aq) Ag2CrO4(s) + KNO3(aq) c. BaCl2(aq) + K2SO4(aq)

> On the basis of the general solubility rules given in Table 7.1, write a balanced molecular equation for the precipitation reactions that take place when the following aqueous solutions are mixed. Underline the formula of the precipitate (solid) that for

> On the basis of the general solubility rules given in Table 7.1, write a balanced molecular equation for the precipitation reactions that take place when the following aqueous solutions are mixed. Underline the formula of the precipitate (solid) that for

> Based on the general solubility rules given in Table 7.1, propose five combinations of aqueous ionic reagents that likely would form a precipitate when they are mixed. Write the balanced full molecular equation and the balanced net ionic equation for eac

> Why is water an important solvent? Although you have not yet studied water in detail, can you think of some properties of water that make it so important?

> Lead(II) nitrate is added to four separate beakers that contain the following: Beaker 1 (sodium chloride) Beaker 2 (sodium hydroxide) Beaker 3 (sodium phosphate) Beaker 4 (sodium sulfate) After the addition of the lead(II) nitrate solution to each b

> What is a net ionic equation? What species are shown in such an equation, and which species are not shown?

> On the basis of the general solubility rules given in Table 7.1, predict the identity of the precipitate that forms when aqueous solutions of the following substances are mixed. If no precipitate is likely, indicate which rules apply. a. copper(II) chlo

> For each of the following precipitation reactions, complete and balance the equation, indicating clearly which product is the precipitate. If no reaction would be expected, so indicate. a. (NH4)2SO4(aq) + Ba(NO3)2(aq) b. H2S(aq) + NiSO4(aq) c. FeCl3

> The formulas Na2O and N2O look very similar. What is the name for each compound? Why do we use a different naming convention between the two compounds?

> Balance each of the following equations that describe precipitation reactions. a. Na2SO4(aq) + CaCl2 (aq) CaSO4(s) + NaCl(aq) b. Co(C2H3O2) 2 (aq) + Na2S(aq) CoS(s) + NaC2H3O2 (aq) c. KOH(aq) + NiC

> Write the name for each of the following binary compounds of nonmetallic elements. a. ClF5 b. XeCl2 c. SeO2 d. N2O3 e. I2Cl6 f. CS2

> Write the name of each of the following binary compounds of nonmetallic elements. a. KrF2 b. Se2S6 c. AsH3 d. XeO4 e. BrF3 f. P2S5

> Write the name of each of the following ionic substances, using -ous or -ic endings to indicate the charge of the cation. a. CoCl2 b. CrBr3 c. PbO d. SnO2 e. Co2O3 f. FeCl3

> Write the name of each of the following ionic substances, using -ous or -ic endings to indicate the charge of the cation. a. CuCl b. Fe2O3 c. Hg2Cl2 d. MnCl2 e. TiO2 f. PbO

> How do we know when a chemical reaction is taking place? Can you think of an example of how each of the five senses (sight, hearing, taste, touch, smell) might be used in detecting when a chemical reaction has taken place?

> Use the information in Table 2.8 to calculate the mass of 50.0 cm3 of each of the following substances. a. gold b. iron c. lead d. aluminum From table 2.8: Table 2.8 Densities of Various Common Substances at 20 °C Substance Physical State Densit

> Use the information in Table 2.8 to calculate the volume of 50.0 g of each of the following substances. a. sodium chloride b. mercury c. benzene d. silver From table 2.8: Table 2.8 Densities of Various Common Substances at 20 °C Substance Physic

> Which of the following is/are examples of a chemical change? a. carving wood b. snow melting c. dry ice subliming (solid CO2 vaporizing into a gas, passing the liquid state) d. burning cookies in the oven

> For Exercises 13–14 Magnesium metal is very malleable and is able to be pounded and stretched into long, thin, narrow “ribbons” that are often used in the introductory chemistry lab as a source of the metal. If a strip of magnesium ribbon is ignited in a

> A material will float on the surface of a liquid if the material has a density less than that of the liquid. Given that the density of water is approximately 1.0 g/mL under many conditions, will a block of material having a volume of 1.2 * 104 in.3 and w

> If 1000. mL of linseed oil has a mass of 929 g, calculate the density of linseed oil.

> Sunflower oil has a density of 0.920 g/mL. What is the mass of 4.50 L of sunflower oil? What volume (in L) would 375 g of sunflower oil occupy?

> By how many places must the decimal point be moved, and in which direction, to convert each of the following to “ordinary” decimal numbers? a. 4.311 * 106 b. 7.895 * 10-5 c. 8.712 * 101 d. 4.995 * 100 e. 2.331 * 1018 f. 1.997 * 10-16

> Write each of the following numbers in standard scientific notation, rounding off the numbers to three significant digits. a. 424.6174 b. 0.00078145 c. 26,755 d. 0.0006535 e. 72.5654

> Although some elements are found in an isolated state, most elements are found combined as with other elements.

> Indicate the number of significant digits in the answer when each of the following expressions is evaluated (you do not have to evaluate the expression). a. (6.25)/(74.1143) b. (1.45)(0.08431)(6.022 * 1023) c. (4.75512)(9.74441)/(3.14)

> The element bromine at room temperature is a liquid with a density of 3.12 g/mL. Calculate the mass of 125 mL of bromine. What volume does 85.0 g of bromine occupy?

> For the masses and volumes indicated, calculate the density in grams per cubic centimeter. a. mass = 4.53 kg; volume = 225 cm3 b. mass = 26.3 g; volume = 25.0 mL c. mass = 1.00 lb; volume = 500. cm3 d. mass = 352 mg; volume = 0.271 cm3

> In a sample of a gaseous substance, more than 99% of the overall volume of the sample is empty space. How is this fact reflected in the properties of a gaseous substance compared with the properties of a liquid or solid substance?

> Referring to Table 2.8, determine whether magnesium, ethanol, silver, or salt is the least dense. From table 2.8: Table 2.8 Densities of Various Common Substances at 20 °C Substance Physical State Density (g/cm³) охудen gas 0.00133* hydrogen gas 0.0

> Referring to Table 2.8, which substance listed is most dense? Which substance is least dense? For the two substances you have identified, for which one would a 1.00-g sample occupy the larger volume? From table 2.8: Table 2.8 Densities of Various Co

> What property of density makes it useful as an aid in identifying substances?

> Is the density of a gaseous substance likely to be larger or smaller than the density of a liquid or solid substance at the same temperature? Why?

> A kilogram of lead occupies a much smaller volume than a kilogram of water because has a much higher density.

> The most common units for density are .

> A sample of matter that is “rigid” has (stronger/weaker) forces among the particles in the sample than does a sample that is not rigid.

> What does the density of a substance represent?

> Perform the indicated temperature conversions. a. 275 K to °C b. 82 °F to °C c. 221 °C to °F d. 240 °F to °C (Notice anything unusual about your answer?)

> The “Chemistry in Focus” segment Tiny Thermometers states that the temperature range for the carbon nanotube gallium thermometers is 50 °C to 500 °C. a. What properties of gallium make it useful in a thermometer? b. Determine the useful temperature ran

> Convert the following Celsius temperatures to Fahrenheit degrees. a. the boiling temperature of ethyl alcohol, 78.1 °C b. a hot day at the beach on a Greek isle, 40. °C c. the lowest possible temperature, 2273 °C d. the body temperature of a person w

> Convert the following Fahrenheit temperatures to Celsius degrees. a. a chilly morning in early autumn, 45 °F b. a hot, dry day in the Arizona desert, 115 °F c. the temperature in winter when my car won’t start, 210 °F d. the surface of a star, 10,000

> Carry out the indicated temperature conversions. a. 2153 °F to kelvins b. 2153 °C to kelvins c. 555 °C to Fahrenheit degrees d. 224 °F to Celsius degrees

> Make the following temperature conversions: a. 44.2 °C to kelvins b. 891 K to °C c. 220 °C to kelvins d. 273.1 K to °C

> On which temperature scale (°F, °C, or K) does 1 degree represent the smallest change in temperature?

> On both the Celsius and Kelvin temperature scales, there are degrees between the normal freezing and boiling points of water.

> The freezing point of water is K.

> What are the two characteristic properties of matter?

> The normal boiling point of water is °F, or °C.

> The point of water is at 32° on the Fahrenheit temperature scale.

> The temperature scale used in everyday life in most of the world except the United States is the scale.

> The radius of an atom is on the order of 10210 m. What is this radius in centimeters? in inches? in nanometers?

> The United States has high-speed trains running between Boston and New York capable of speeds up to 160 mi/h. Are these trains faster or slower than the fastest trains in the United Kingdom, which reach speeds of 225 km/h?

> Los Angeles and Honolulu are 2558 mi apart. What is this distance in kilometers?

> 12.01 g of carbon contains 6.02 * 1023 carbon atoms. What is the mass in grams of 1.89 * 1025 carbon atoms?

> Which of the following statements is(are) true? a. A spoonful of sugar is a mixture. b. Only elements are pure substances. c. Air is a mixture of gases. d. Gasoline is a pure substance. e. Compounds can be broken down only by chemical means.

> Which of the following best describes the substance XeF4? a. element b. compound c. heterogeneous mixture d. homogeneous mixture

> The properties of a compound are often very different from the properties of the elements making up the compound. Water is an excellent example of this idea. Discuss.

> Will the power of 10 have a positive, negative, or zero exponent when each of the following numbers is rewritten in standard scientific notation? a. 0.08331 b. 2.8 c. 0.0491 d. 70,892,000

> Sketch the apparatus commonly used for simple distillation in the laboratory, identifying each component.

> For Exercises 57 and 58, apples cost $1.75 per pound. What conversion factor could be used to determine how many pounds of apples could be bought for $25.00?

> For Exercises 57 and 58, apples cost $1.75 per pound. What conversion factor is appropriate to express the cost of 5.3 lb of apples?

> Given that 1 in. = 2.54 cm exactly, indicate what conversion factor is appropriate to convert 3.25 in. to centimeters and to convert 46.12 cm to inches.

> Given that 1 mi = 1760 yd, determine what conversion factor is appropriate to convert 1849 yd to miles; to convert 2.781 mi to yards.

> How many significant figures are understood for the numbers in the following definition: 1 in. = 2.54 cm?

> A represents a ratio based on an equivalence statement between two measurements.

> Which of the following best describes the air around you on a typical day? (Assume the air is made up of ,80% nitrogen and ,20% oxygen. Ignore other gases such as water vapor and carbon dioxide.). a. Air is a homogeneous mixture of gases because it gene

> How many significant digits should be used to report the answer to each of the following calculations? Do not perform the calculations. a. (2.7518 + 9.01 + 3.3349)/(2.1) b. (2.7751 * 1.95)/(.98) c. 12.0078/3.014 d. (0.997 + 4.011 + 3.876)/(1.86 * 10-

> Which of the following contains an element, a compound, and a mixture? a. copper, silicon dioxide (SiO2), copper(II) sulfate (CuSO4) b. hydrogen, carbon dioxide (CO2), water (H2O) c. chili, pizza, steak d. sodium, sodium chloride (NaCl), salt water e

> Will the power of 10 have a positive or a negative exponent when each of the following numbers is rewritten in standard scientific notation? a. 42,751 b. 1253 c. 0.002045 d. 0.1089

> Without actually performing the calculations indicated, tell to how many significant digits the answer to the calculation should be expressed. a. (0.196)(0.08215)(295)/(1.1) b. (4.215 + 3.991 + 2.442)/(0.22) c. (7.881)(4.224)(0.00033)/(2.997) d. (6.2

> A(n) always has the same composition.

> The processes of melting and evaporation involve changes in the of a substance.

> How many digits after the decimal point should be reported when the calculation (10,434 -9.3344) is performed?

> When the sum 4.9965 + 2.11 + 3.887 is calculated, to how many decimal places should the answer be reported? You should not need to perform the calculation.

> Which of the following are true? a. P4 is considered a compound. b. Metal rusting on a car is a chemical change. c. Dissolving sugar in water is a chemical change. d. Sodium chloride (NaCl) is a homogeneous mixture.

> When the calculation (2.31)(4.9795 * 103)/(1.9971 * 104) is performed, how many significant digits should be reported for the answer? You should not need to perform the calculation.

> The following water measurements are made: 18 mL of water measured with a beaker, 128.7 mL of water measured with a graduated cylinder, and 23.45 mL of water measured with a buret. If all of these water samples are then poured together into one container

> Consider the calculation indicated below: Explain why the answer to this calculation should be reported to only two significant digits. 2.21 x 0.072333 × 0.15 4.995

> Round off each of the following numbers to the indicated number of significant digits, and write the answer in standard scientific notation. a. 0.00034159 to two digits b. 103.351 * 102 to five digits c. 17.9915 to one digit d. 3.365 * 105 to four di

> When a large or small number is written in standard scientific notation, the number is expressed as the product of a number between 1 and 10, multiplied by the appropriate power of 10. For each of the following numbers, indicate what power of 10 would be

> Round off each of the following numbers to the indicated number of significant digits and write the answer in standard scientific notation. a. 4341 * 102 to three significant digits b. 93.441 * 103 to three significant digits c. 0.99155 * 102 to four

> Round off each of the following numbers to two significant digits, and express the result in standard scientific notation. a. 1,566,311 b. 2.7651 * 10-3 c. 0.07759 d. 0.0011672

> Round off each of the following numbers to three significant digits, and express the result in standard scientific notation. a. 254,931 b. 0.00025615 c. 47.85 * 103 d. 0.08214 * 105

> In a multiple-step calculation, is it better to round off the numbers to the correct number of significant figures in each step of the calculation or to round off only the final answer? Explain.