Air entering the lungs ends up in tiny sacs called alveoli. It is from the alveoli that oxygen diffuses into the blood. The average radius of the alveoli is 0.0050 cm and the air inside contains 14...
A student breaks a thermometer and spills most of the mercury (Hg) onto the floor of a laboratory that measures 15.2 m long, 6.6 m wide, and 2.4 m high. (a) Calculate the mass of mercury vapor (in...
(a) What volume of air at 1.0 atm and 22C is needed to fi ll a 0.98-L bicycle tire to a pressure of 5.0 atm at the same temperature? (The 5.0 atm is the gauge pressure, which is the difference...
A student tries to determine the volume of a bulb like the one shown on p. 192. These are her results: Mass of the bulb filled with dry air at 23C and 744 mmHg = 91.6843 g; mass of evacuated bulb 5...
Apply your knowledge of the kinetic theory of gases to the following situations. (a) Two flasks of volumes V1 and V2 (V2. V1) contain the same number of helium atoms at the same temperature. (i)...
A relation known as the barometric formula is useful for estimating the change in atmospheric pressure with altitude. The formula is given by P = P0e-gmhyRT, where P and P 0 are the pressures at...
A mixture of calcium carbonate (CaCO3) and magnesium carbonate (MgCO3) of mass 6.26 g reacts completely with hydrochloric acid (HCl) to generate 1.73 L of CO2 at 48C and 1.12 atm. Calculate the mass...
A stockroom supervisor measured the contents of a partially filled 25.0-gallon acetone drum on a day when the temperature was 18.0C and atmospheric pressure was 750 mmHg, and found that 15.4 gallons...
A mixture of methane (CH4) and ethane (C2H6) is stored in a container at 294 mmHg. The gases are burned in air to form CO2 and H2O. If the pressure of CO2 is 356 mmHg measured at the same temperature...
A sample of air occupies 3.8 L when the pressure is 1.2 atm. (a) What volume does it occupy at 6.6 atm? (b) What pressure is required in order to compress it to 0.075 L? (The temperature is kept...
Ammonia burns in oxygen gas to form nitric oxide (NO) and water vapor. How many volumes of NO are obtained from one volume of ammonia at the same temperature and pressure?
A sample of nitrogen gas kept in a container of volume 2.3 L and at a temperature of 32C exerts a pressure of 4.7 atm. Calculate the number of moles of gas present.
An ideal gas originally at 0.85 atm and 66C was allowed to expand until its final volume, pressure, and temperature were 94 mL, 0.60 atm, and 45C, respectively. What was its initial volume?
Assuming that air contains 78 percent N2, 21 percent O2, and 1 percent Ar, all by volume, how many molecules of each type of gas are present in 1.0 L of air at STP?
A quantity of 0.225 g of a metal M (molar mass = 27.0 g/mol) liberated 0.303 L of molecular hydrogen (measured at 17C and 741 mmHg) from an excess of hydrochloric acid. Deduce from these data the...
A mixture of gases contains 0.31 mol CH4, 0.25 mol C2H6, and 0.29 mol C3H8. The total pressure is 1.50 atm. Calculate the partial pressures of the gases.
A mixture of helium and neon gases is collected over water at 28.0C and 745 mmHg. If the partial pressure of helium is 368 mmHg, what is the partial pressure of neon? (Vapor pressure of water at 28C...
A piece of sodium metal reacts completely with water as follows: 2Na(s) + 2H2O(l) 2NaOH(aq) + H2(g) The hydrogen gas generated is collected over water at 25.0C. The volume of the gas is 246 mL...
A sample of zinc metal reacts completely with an excess of hydrochloric acid: Zn(s) + 2HCl(aq) ZnCl2(aq) + H2(g) The hydrogen gas produced is collected over water at 25.0C using an arrangement...
The enthalpy of combustion of benzoic acid (C6H5COOH) is commonly used as the standard for calibrating constant-volume bomb calorimeters; its value has been accurately determined to be -3226.7...
Acetylene (C2H2) and benzene (C6H6) have the same empirical formula. In fact, benzene can be made from acetylene as follows: The enthalpies of combustion for C2H2 and C6H6 are -1299.4 kJ/mol and...
Ice at 0C is placed in a Styrofoam cup containing 361 g of a soft drink at 23C. The specific heat of the drink is about the same as that of water. Some ice remains after the ice and soft drink reach...
A gas company in Massachusetts charges $1.30 for 15 ft3 of natural gas (CH4) measured at 20C and 1.0 atm. Calculate the cost of heating 200 mL of water (enough to make a cup of coffee or tea) from...
A quantity of 2.00 ( 102 mL of 0.862 M HCl is mixed with 2.00 (102 mL of 0.431 M Ba(OH)2 in a constant-pressure calorimeter of negligible heat capacity. The initial temperature of the HCl and Ba(OH)2...
Calculate the work done (in joules) when 1.0 mole of water is frozen at 0C and 1.0 atm. The volumes of one mole of water and ice at 0C are 0.0180 L and 0.0196 L, respectively?
A quantity of 0.020 mole of a gas initially at 0.050 L and 20C undergoes a constant-temperature expansion until its volume is 0.50 L. Calculate the work done (in joules) by the gas if it expands (a)...
A ruby laser produces radiation of wavelength 633 nm in pulses whose duration is 1.00 10-9 s. (a) If the laser produces 0.376 J of energy per pulse, how many photons are produced in each pulse? (b)...
A n electron in an excited state in a hydrogen atom can return to the ground state in two different ways: (a) Via a direct transition in which a photon of wavelength 1 is emitted (b) Via an...
A photoelectric experiment was performed by separately shining a laser at 450 nm (blue light) and a laser at 560 nm (yellow light) on a clean metal surface and measuring the number and kinetic energy...
Ionization energy is the minimum energy required to remove an electron from an atom. It is usually expressed in units of kJ/mol, that is, the energy in kilojoules required to remove one mole of...
A photon has a frequency of 6.0 104 Hz. (a) Convert this frequency into wavelength (nm). Does this frequency fall in the visible region? (b) Calculate the energy (in joules) of this photon. (c)...
A particular form of electromagnetic radiation has a frequency of 8.11 1014 Hz. (a) What is its wavelength in nanometers? In meters? (b) To what region of the electromagnetic spectrum would you...
An electron in the hydrogen atom makes a transition from an energy state of principal quantum numbers n I to the n = 2 state. If the photon emitted has a wavelength of 434 nm, what is the value of ni?
An electron in a certain atom is in the n = 2 quantum level. List the possible values of and m that it can have.
An electron in an atom is in the n = 3 quantum level. List the possible values of and m that it can have.
(a) What is the wavelength (in nanometers) of light having a frequency of 8.6 1013 Hz? (b) What is the frequency (in Hz) of light having a wavelength of 566 nm?
(a) What is the frequency of light having a wavelength of 456 nm? (b) What is the wavelength (in nanometers) of radiation having a frequency of 2.45 109 Hz? (This is the type of radiation used in...
What is the maximum number of electrons in an atom that can have the following quantum numbers? Specify the orbitals in which the electrons would be found. (a) n = 2, ms = + 1/2; (b) n = 4, m = 11;...
An element X reacts with hydrogen gas at 200C to form compound Y. When Y is heated to a higher temperature, it decomposes to the element X and hydrogen gas in the ratio of 559 mL of H2 (measured at...
A student is given samples of three elements, X, Y, and Z, which could be an alkali metal, a member of Group 4A, and a member of Group 5A. She makes the following observations: Element X has a...
As discussed in the chapter, the atomic mass of argon is greater than that of potassium. This observation created a problem in the early development of the periodic table because it meant that argon...
(a) The formula of the simplest hydrocarbon is CH4 (methane). Predict the formulas of the simplest compounds formed between hydrogen and the following elements: silicon, germanium, tin, and lead. (b)...
As mentioned in Chapter 3 (p. 108), ammonium nitrate (NH4 NO3) is the most important nitrogen-containing fertilizer in the world. Describe how you would prepare this compound, given only air and...
A neutral atom of a certain element has 17 electrons. Without consulting a periodic table, (a) Write the ground-state electron configuration of the element, (b) Classify the element, (c) Determine...
A metal ion with a net +3 charge has five electrons in the 3d sub shell. Identify the metal.
Arrange the following atoms in order of decreasing atomic radius: Na, Al, P, Cl, Mg.
Two atoms have the electron configurations 1s22s22p6 and 1s22s22p63s1. The first ionization energy of one is 2080 kJ/mol, and that of the other is 496 kJ/mol. Match each ionization energy with one of...
Arrange the elements in each of the following groups in increasing order of the most positive electron affinity: (a) Li, Na, K; (b) F, Cl, Br, I; (c) O, Si, P, Ca, Ba.
As a group, the noble gases are very stable chemically (only Kr and Xe are known to form compounds). Use the concepts of shielding and the effective nuclear charge to explain why the noble gases tend...
Arrange the following species in isoelectronic pairs: O+, Ar, S2-, Ne, Zn, Cs+, N3-, As3+, N, Xe.
In which of the following are the species written in decreasing order by size of radius? (a) Be, Mg, Ba, (b) N3-, O2-, F-, (c) Tl3+, Tl2+, Tl+.
Although nitrogen dioxide (NO2) is a stable compound, there is a tendency for two such molecules to combine to form dinitrogen tetroxide (N2O4). Why? Draw four resonance structures of N2O4, showing...
In the gas phase, aluminum chloride exists as a dimer (a unit of two) with the formula Al2Cl6. Its skeletal structure is given by Complete the Lewis structure and indicate the coordinate covalent...
Among the common inhaled anesthetics are: Halothane: CF3CHClBr Enflurane: CHFClCF2OCHF2 Isoflurane: CF3CHClOCHF2 Methoxyflurane: CHCl2CF2OCH3 Draw Lewis structures of these molecules
A student in your class claims that magnesium oxide actually consists of Mg+ and O- ions, not Mg2+ and O2- ions. Suggest some experiments one could do to show that your classmate is wrong
An ionic bond is formed between a cation A+ and an anion B-. How would the energy of the ionic bond be affected by the following changes? (a) Doubling the radius of A+, (b) Tripling the charge on A+,...
Arrange the following bonds in order of increasing ionic character: carbon to hydrogen, fluorine to hydrogen, bromine to hydrogen, sodium to chlorine, potassium to fluorine, lithium to chlorine.
Are the following statements true or false? (a) Formal charges represent actual separation of charges. (b) Hrxn can be estimated from the bond enthalpies of reactants and products. (c) All...
A rule for drawing plausible Lewis structures is that the central atom is invariably less electronegative than the surrounding atoms. Explain why this is so. Why does this rule not apply to compounds...
Aluminum trichloride (AlCl3) is an electron- deficient molecule. It has a tendency to form a dimer (a molecule made of two AlCl3 units): (a) Draw a Lewis structure for the dimer. (b) Describe the...
How many pi bonds and sigma bonds are there in the tetracyanoethylene molecule? N=C C=N C=C C=N N=C
Arrange the following species in order of increasing stability: Li2, Li2+, Li2-2. Justify your choice with a molecular orbital energy level diagram?
Acetylene (C2H2) has a tendency to lose two protons (H1) and form the carbide ion (C22-), which is present in a number of ionic compounds, such as CaC2 and MgC2. Describe the bonding scheme in the...
A single bond is almost always a sigma bond, and a double bond is almost always made up of a sigma bond and a pi bond. There are very few exceptions to this rule. Show that the B2 and C2 molecules...
Although both carbon and silicon are in Group 4A, very few Si=Si bonds are known. Account for the instability of silicon-to-silicon double bonds in general. (Compare the atomic radii of C and Si in...
Antimony pentafluoride, SbF5, reacts with XeF4 and XeF6 to form ionic compounds, XeF3+SbF6- and XeF5+ SbF6-. Describe the geometries of the cations and anion in these two compounds?
Ammonia is both a donor and an acceptor of hydrogen in hydrogen-bond formation. Draw a diagram showing the hydrogen bonding of an ammonia molecule with two other ammonia molecules?
A small drop of oil in water assumes a spherical shape. Explain. (Oil is made up of nonpolar molecules, which tend to avoid contact with water.)
Argon crystallizes in the face-centered cubic arrangement at 40 K. Given that the atomic radius of argon is 191 pm, calculate the density of solid argon?
Classify the solid state of the following substances as ionic crystals, covalent crystals, molecular crystals, or metallic crystals: (a) CO2, (b) B12, (c) S8, (d) KBr, (e) Mg, (f) SiO2, (g) LiCl, (h)...
A phase diagram of water is shown at the end of this problem. Label the regions. Predict what would happen as a result of the following changes: (a) Starting at A, we raise the temperature at...
Name the kinds of attractive forces that must be overcome in order to (a) Boil liquid ammonia, (b) Melt solid phosphorus (P4), (c) Dissolve CsI in liquid HF, (d) Melt potassium metal.
A mixture of NaCl and sucrose (C12H22O11) of combined mass 10.2 g is dissolved in enough water to make up a 250 mL solution. The osmotic pressure of the solution is 7.32 atm at 23C. Calculate the...
A solution contains two volatile liquids A and B. Complete the following table, in which the symbol indicates attractive intermolecular forces. Deviation from Attractive Forces Raoult's Law AH soln...
Arrange the following compounds in order of increasing solubility in water: O2, LiCl, Br2, methanol (CH3OH).
A mixture of ethanol and 1-propanol behaves ideally at 36C and is in equilibrium with its vapor. If the mole fraction of ethanol in the solution is 0.62, calculate its mole fraction in the vapor...
Acetic acid is a weak acid that ionizes in solution as follows: If the freezing point of a 0.106 m CH 3 COOH solution is 20.203C, calculate the percent of the acid that has undergone ionization....
Acetic acid is a polar molecule and can form hydrogen bonds with water molecules. Therefore, it has a high solubility in water. Yet acetic acid is also soluble in benzene (C6H6), a nonpolar solvent...
As we know, if a soft drink can is shaken and then opened, the drink escapes violently. However, if after shaking the can we tap it several times with a metal spoon, no such "explosion" of the drink...
An example of the positive deviation shown in Figure 12.8(a) is a solution made of acetone (CH3COCH3) and carbon disulfide (CS2). (a) Draw Lewis structures of these molecules. Explain the deviation...
A very long pipe is capped at one end with a semipermeable membrane. How deep (in meters) must the pipe be immersed into the sea for freshwater to begin to pass through the membrane? Assume the water...
A mixture of liquids A and B exhibits ideal behavior. At 84C, the total vapor pressure of a solution containing 1.2 moles of A and 2.3 moles of B is 331 mmHg. Upon the addition of another mole of B...
A student carried out the following procedure to measure the pressure of carbon dioxide in a soft drink bottle. First, she weighed the bottle (853.5 g). Next, she carefully removed the cap to let the...
Calculate the molality of each of the following aqueous solutions: (a) 2.50 M NaCl solution (density of solution = 1.08 g/mL), (b) 48.2 percent by mass KBr solution.
The concentrated sulfuric acid we use in the laboratory is 98.0 percent H2SO4 by mass. Calculate the molality and molarity of the acid solution. The density of the solution is 1.83 g/mL.
The solubility of KNO3 is 155 g per 100 g of water at 75C and 38.0 g at 25C. What mass (in grams) of KNO3 will crystallize out of solution if exactly 100 g of its saturated solution at 75C is cooled...
The solubility of N2 in blood at 37C and at a partial pressure of 0.80 atm is 5.6 3 1024 mol/L. A deepsea diver breathes compressed air with the partial pressure of N2 equal to 4.0 atm. Assume that...
A solution is prepared by dissolving 396 g of sucrose (C12H22O11) in 624 g of water. What is the vapor pressure of this solution at 30C? (The vapor pressure of water is 31.8 mmHg at 30C.)
How many grams of sucrose (C12H22O11) must be added to 552 g of water to give a solution with a vapor pressure 2.0 mmHg less than that of pure water at 20C? (The vapor pressure of water at 20C is...
The vapor pressure of ethanol (C2H5OH) at 20C is 44 mmHg, and the vapor pressure of methanol (CH3OH) at the same temperature is 94 mmHg. A mixture of 30.0 g of methanol and 45.0 g of ethanol is...
A solution is prepared by condensing 4.00 L of a gas, measured at 27C and 748 mmHg pressure, into 58.0 g of benzene. Calculate the freezing point of this solution.
A quantity of 7.480 g of an organic compound is dissolved in water to make 300.0 mL of solution. The solution has an osmotic pressure of 1.43 atm at 27C. The analysis of this compound shows that it...
Which of the following aqueous solutions has (a) The higher boiling point, (b) The higher freezing point, and (c) The lower vapor pressure: 0.35 m CaCl2 or 0.90 m urea? Explain. Assume CaCl2 to...
Arrange the following solutions in order of decreasing freezing point: 0.10 m Na3PO4, 0.35 m NaCl, 0.20 m MgCl2, 0.15 m C6H12O6, 0.15 m CH3COOH.
Arrange the following aqueous solutions in order of decreasing freezing point, and explain your reasoning: 0.50 m HCl, 0.50 m glucose, 0.50 m acetic acid.
What are the normal freezing points and boiling points of the following solutions? (a) 21.2 g NaCl in 135 mL of water (b) 15.4 g of urea in 66.7 mL of water
The osmotic pressure of 0.010 M solutions of CaCl2 and urea at 25C are 0.605 atm and 0.245 atm, respectively. Calculate the van't Hoff factor for the CaCl2 solution.
A solution of 1.00 g of anhydrous aluminum chloride, AlCl3, in 50.0 g of water freezes at 21.11C. Does the molar mass determined from this freezing point agree with that calculated from the formula?...
A nonvolatile organic compound Z was used to make up two solutions. Solution A contains 5.00 g of Z dissolved in 100 g of water, and solution B contains 2.31 g of Z dissolved in 100 g of benzene. A...
Consider the following equilibrium process at 700C: Analysis shows that there are 2.50 moles of H2, 1.35 10-5 mole of S2, and 8.70 moles of H2S present in a 12.0-L fl ask. Calculate the equilibrium...