Which has more atoms: 1 kg of iron or 1 kg of aluminum? See*rtur 46rk8w u the periodic table or Appr8tw4*r 6ruku endix B.

Name several properties of materials that could be exploiteds,dl m;m)92e8on ilrj to make a thermomet,n29)lioj dsm l8re m;er.

Which is larger, 1 C4pt/p90rov f l $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with systez48i( un.y ruj *bzevtr22 4zim B, but B is not in thermal equilibrium with system C, what can* i2nz2eui4vjz(t zrb .r84yu you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to :l/xllxfx:; karo8yz65s (rba strip of iron. When heated, the strip will bend. Which metal will be on the outside of the curve? [Hint: See Tablerx8l6x( l zf :r/k: sxy;5lboa 13–1.] Why?

In the relation $\Delta$L = $\alpha$ $L_0$ $\Delta$T, should $L_0$ be the initial length, the final length, or does it matter? Explain.

The units for the coe. -ldy2 4pc)zmfvnj ozc*w/e6fficient of linear expansion $\alpha$ are $(C?)^{-1}$ and there is no mention of a length unit such as meters. Would the expansion coefficient change if we used feet or millimeters instead of meters? Explain.

Figure 13–27 shows a diagram of a simple thermostat used to control a furnakzl jv171i tug6*.l jtce (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch is a glass vessel containing lig ulj * jvttz.1ki7l61quid mercury that conducts electricity when it can flow to touch both contact wires. Explain how this device controls the furnace and how it can be set at different temperatures.

Long steam pipes that are fixed at the ends often have a section in tho :j4nof;zx9 rg 1nme6e shape of a U. Whynoorzf x 9g;:en4m6 1j?

A flat, uniform cylinder of lead floats in mercury as xq00xt l.1k3aw:mzzt 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometer is first placed ixv,-nz)kb/)kh3 jxt o n a hot tub of water, the mercury initially descends a bit and then rises. Expn, bx/3vk )z)hjxto-klain.

A glass container may break if one part of it is he t4f .nm;zxmu0ated or cooled more rapidly than adjaceu 0f.4 mnzt;xmnt parts. Explain.

The principal virtue of Pyrex glass is td;d:ztdyv+x go)6ps3 hat its coefficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why t x6o zgtdyd :v+sd3;)phis gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurate atftl 9oe;g,00h7m mia xqxn8/r 20 $^{\circ} $ C, run fast or slow on a hot day (30 $^{\circ} $ C)? Explain. The clock uses a pendulum supported on a long, thin brass rod.

Freezing a can of soda w 5pk:imy 9uv9tl4y zbq):vd y5f,qz(xill cause its bottom and top to bulge so badly the can will not stand ybtvm:ud 5 )yqf p4v9:9zkziq y5xl ,(up. What has happened?

When a gas is rapidly compressed (say, by pushimmv-*jaru4rr*ce) 8 vng down a piston), its temperature increases. When a gas expands 4*m-c )rvr* euajrv8m against a piston, it cools. Explain these changes in temperature using the kinetic theory, in particular noting what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force on an aluminum sphiv;xeu vrldlm(1 u.-a:s 0s.y ere submerged in water increase or decrease if the temperature is increased from1 suel ixr.-m(ayv:0udvl .;s 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s l , i3.staxsj6yaw follows from kinetic theory and the relation between average kinetic ene6s3 .st,xijy argy and the absolute temperature.

Explain in words how Gay- q*dpz9*7v kiiLussac’s law follows from kinetic theory.

As you go higher in the Earth’s atmosphere,e8qr+ seb7(aed z185axu;bn y the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Eaxy5v j, mcvc f31)4,m7ps gtpp:/ituarth refers to the minimum speed an object must have to leave the Earth and never return. The escape velocity for the Moon is about one-fifth what it is for the Earth due to the Moon’s smaller mass. Explain why th:u, cpyg4vpi3mtaf st,1v7 m/cj5x)pe Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at room temperature. Whap+ s yas*iwn) yy,p(zzczy 81,t can you infer about the mo ,yic 8y(zppsy,w+) z*nzy1sa lecular properties of one relative to the other?

Explain why a hot humid(t /bhpl+ srs6/byy t :ojfzmq52+g0v day is far more uncomfortable than a hot dry day at the frsbslboq6+:/m vhz+yt j0 /2yp(5gtsame temperature.

Is it possible to boil water acgcma , 3(uvy14dgpo3t room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the sace.c(q4xw9gkhbty b29 w6uj.me but the humidity is different. Which is more dense, the dry air or the humigjq .cycu e4x62b.bkthw( 99wd air at the same T? Explain.

Explain why it is dangerous to open s dsxsiz3 ti49 w vja htn(;.3:cg:4qvthe radiator cap of an overheated automobile eng.::v43iasshs3 qt(igdc;9z xv4 jt n wine.

Why does exhaled air u/b6fqr /.nci joysth7 89u.mappear as a little white cloud in the winter (Fig. 13–28)?

  How many atoms are thqn 92fr (dwhf+w,dr-pere in a 3.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms *xvt.s n6rz6b1wc po qs )okxxz(yev,7.au- 9in a 26.5-gram gold ring compare to the number in a k,o uo*bavesq pztxsw7x(n 6)1.6.yrx vzc 9-silver ring of the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this on the Celsius sca28 ..qg)u.la nh eeak)32vuttcd hlq.x.qj; x le?guq.v d2x8tehn.qk uce h 3la;)qta.xl .j.2)   $^{\circ} $ C
(b) The temperature of the filament in a lightbulb is about 1800 $^{\circ} $ C. What is this on the Fahrenheit scale?    $^{\circ} $ F

  Among the highest an6 6kvkg2izh/bd lowest temperatures recorded are 136 $^{\circ} $F in the Libyan desert and -129 $^{\circ} $F in Antarctica. What are these temperatures on the Celsius scale?high =    $^{\circ} $ C
low =    $^{\circ} $ C

  (a) 15 $^{\circ} $ below zero on the Celsius scale is what Fahrenheit temperature?    $^{\circ} $ F
(b) 15 $^{\circ} $ below zero on the Fahrenheit scale is what Celsius temperature?   $^{\circ} $ C

  In an alcohol-in-glass thermometer, the alcks,o(qv9kqn0. x(vj zh0z cm) ohol column has length 11.82 cm at 0. 9zkvsqq0(ck.v0x nzjh o )(m,0 $^{\circ} $ C and length 22.85 cm at 100.0 $^{\circ} $ C. What is the temperature if the column has length
(a) 16.70 cm,    $^{\circ} $ C
(b) 20.50 cm?    $^{\circ} $ C

  A concrete highway is built of slabs 12 fq 5 2o7y+5s3iakbrblm long (20 $^{\circ} $ C). How wide should the expansion cracks between the slabs be (at 20 $^{\circ} $ C) to prevent buckling if the range of temperature is -30 $^{\circ} $ C to +50 $^{\circ} $ C?    m

  Super Inva$^{TM}$, an alloy of iron and nickel, is a strong material with a very low coefficient of linear expansion [0.2$ \times10^{ -6}$(C?)$^{-1}$]
A 2.0-m-long tabletop made of this alloy is used for sensitive laser measurements where extremely high tolerances are required. How much will this table expand along its length if the temperature increases 5.0 $^{\circ} $ C? Compare to tabletops made of steel.   $ \times10^{-6 }$ m    $ \times10^{-4 }$ m

  The Eiffel Tower (Fig. 13–29) is built of wrovo2.4r ylhvg*t( um1 ought iron approximately 300 m tall. Estimate how much its heightu*ly4 v o g21(rmhvt.o changes between July (average temperature of 25°C) and January (average temperature of 2 $^{\circ} $ C). Ignore the angles of the iron beams, and treat the tower as a vertical beam.    m

  To make a secure fit, rivets that are larger than the rivet mxm*ptmz;p/r24 j(t rhole are often used and the rivet is cooled (usually in dry ice) before it is placed in the hole. A strmxpmzr t4t (m2/*;jp eel rivet 1.871 cm in diameter is to be placed in a hole 1.869 cm in diameter at 20 $^{\circ} $ C. To what temperature must the rivet be cooled if it is to fit in the hole?    $^{\circ} $ C

  The density of water at 43pq6 o svzs +o0dk,h,zjy7e.i $^{\circ} $ C is $ 1\times10^{3 }kg/m^3$ What is water’s density at 94 $^{\circ} $ C?    kg/$m^3$

  A quartz sphere is 8.75 cm in 6se6wck93er s* t4bvsdiameter. What will be its change in volume if it is heated from w3ek4t ess6*rbc69 vs30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350.0 mL of water at 1x* r+ipbt((w ji*(y ojyjtl*,00.0$^{\circ} $ C. If the temperature decreased to 20.0 $^{\circ} $ C, how much water could be added to the glass?    mL

  It is observed that 55.50 mL of water ac0t g6qt3uj7xt 20 $^{\circ} $ C completely fills a container to the brim. When the container and the water are heated to 60 $^{\circ} $ C, 0.35 g of water is lost. (a) What is the coefficient of volume expansion of the container?    $ \times10^{-5 }$ /$C^0$(b) What is the most likely material of the container? The density of water at 60°C is 0.98324g/ml.

  (a) A brass plug is to be placed in a ring ma60i2kk k 0qdqqde of iron. At 20 $^{\circ} $ C, the diameter of the plug is 8.753 cm and that of the inside of the ring is 8.743 cm. They must both be brought to what common temperature in order to fit?    $^{\circ} $ C
(b) What if the plug were iron and the ring brass?    $^{\circ} $ C

If a fluid is contained in a long, narrow vessel so it can expanr z-zs5 smjl8ec+(d8 dax-wq)d in essentially one direction only, show that the effectivez8a-d -z 5(me xqlsd c)j8wrs+ coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change iel c3iemo;c2 4n the density $\rho$ of a substance, when the temperature changes by $\Delta$T is given by $\rho$ = -$\beta$$\rho$$\Delta$T
(b) What is the fractional change in density of a lead sphere whose temperature decreases from 25 $^{\circ} $ C to -40 $^{\circ} $ C？

A uniform rectangular plate of length l and width w has coefficient of linte15u d*d-r 8br1eocgear expansion gb*8er -r 1dcotu51de$\alpha$ Show that, if we neglect very small quantities, the change in area of the plate due to a temperature change $\Delta$T is $\Delta$A = 2$\alpha l w$$\Delta$T See Fig. 13–30.

Show that for an isotropic solid, 6) w mkv lh-66sggw:an$\beta$ = 3$\alpha$ if the amount of expansion is small. $\beta$ and $\alpha$ are the coefficients of volume and linear expansion, respectively. [Hint: Consider a cubical solid, and neglect very small quantities. See also Problem 18 and Fig. 13–30.]

  The pendulum in a grandfather clock is m ks4y4zv 45 bc9g/ nex(r.ejsx :j-cxgade of brass and keeps perfect time at 17 4sxkc yx5: esx/( z g4.94njgbv-jrce$^{\circ} $ C. How much time is gained or lost in a year if the clock is kept at 25 $^{\circ} $ C? (Assume the frequency dependence on length for a simple pendulum applies.)$\approx$    min(Round to the nearest integer)

  (a) The tube of a mercury thermor/10 xz,wttdkwo ky*6meter has an inside diameter of 0.140 mm. The bul z1w/y0 r,ow*6 kkttxdb has a volume of 0.255 $cm^3$ How far will the thread of mercury move when the temperature changes from 11.5 $^{\circ} $ C to 33.0 $^{\circ} $ C? Take into account expansion of the Pyrex glass.    cm(b) Determine a formula for the length of the mercury column in terms of relevant variables. Ignore tube volume compared to bulb volume.

  A 23.4-kg solid aluminum cylindrical wheel of radius 0.41 m is rotating about itaxng, dxno8:6c 2knqqr)48mm s8: x q,6km8n crao)m gdxnn2q4 axle on frictionless bearings with angular velocity $\omega$ = 32.8 rad/s If its temperature is now raised from 20.0 $^{\circ} $ C to 75.0 $^{\circ} $ C, what is the fractional change in $\omega$?   

  An aluminum bar has i/i kmaad4l07 the desired length when at 15°C. How much stress is required t/40aim aidkl7o keep it at this length if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam ofp0tnmgj7 6glua9n ifbeaf+9(5 vk 7b 8 cross-sectional area 0.041$m^2$ is rigidly connected to two vertical steel girders. If the beam was installed when the temperature was 30$^{\circ} $ C, what stress is developed in the beam when the temperature drops to -30 $^{\circ} $ C (b) Is the ultimate strength of the steel exceeded? (c) What stress is developed if the beam is concrete and has a cross-sectional area of 0.13$m^2$ Will it fracture?

  A barrel of diameter 13u qj8,5u .gheko/b 0qa4.122 cm at 20$^{\circ} $ C is to be enclosed by an iron band. The circular band has an inside diameter of 134.110 cm at 20$^{\circ} $ C. It is 7.4 cm wide and 0.65 cm thick.
(a) To what temperature must the band be heated so that it will fit over the barrel? $\approx$   $^{\circ} $ C(Round to the nearest integer)
(b) What will be the tension in the band when it cools to 20$^{\circ} $ C?    N

  What are the following temperaturew;-,na xnj 5eqs on the Kelvin scale:
(a) 86$^{\circ} $ C,    K
(b) 78$^{\circ} $F,    K
(c) -100$^{\circ} $C    K
(d) 5500°C,    K
(e) -459$^{\circ} $F    K

  Absolute zero is what temperature on the Fahre*bdu0ex l9*a nv,i*wv( g 1wvvnheit scale?    $^{\circ} $ F

  Typical temperatures in the int*v-+0piy dn cd ene.-derior of the Earth and Sun are about 4000$^{\circ} $ C and $ \times10^{6 }$ $^{\circ} $ C respectively.
(a) What are these temperatures in kelvins?    K    $ \times10^{ 6}$K
(b) What percent error is made in each case if a person forgets to change $^{\circ} $ C to K? $\approx$    %(Round to the nearest integer) $\approx$    %(Round to three decimal places)

  If 3 $m^2$ of a gas initially at STP is placed under a pressure of 3.20 atm, the temperature of the gas rises to 38.0$^{\circ} $ C. What is the volume?    $m^3$

  In an internal combustion engine/,u0/aaqif7rm ka: xdtcq1p(, air at atmospheric pressure and a temperature of about 2rau1xaqa/f: i(tdpc7k 0q m/, 0$^{\circ} $C is compressed in the cylinder by a piston to $\frac{1}{9}$ of its original volume (compression ratio = 9.0). Estimate the temperature of the compressed air, assuming the pressure reaches 40 atm.    $^{\circ} $ C

  Calculate the density (d hesxl - 4/;c 8fe;tr-kouloof oxygen at STP using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg ovu-*r19 :b u+z )ij y2rqt iufjsqg255 tau;hzf nitrogen ($N_2$) at an absolute pressure of 3.65 atm. What will the pressure be if the nitrogen is replaced by an equal mass of $CO_2$    atm

  A storage tank at STP contax65m+lg lrdstn6t+ (a2 vqcfc4gd8 c4ins 18.5 kg of nitrogen ($N_2$)
(a) What is the volume of the tank? $\approx$   $m^3$(“Round to one decimal places)
(b) What is the pressure if an additional 15.0 kg of nitrogen is added without changing the temperature?    $ \times10^{5 }$Pa    atm

  If 18.75 mol of helium gas is at 104j8ydc* hayi9 6ckqa-l: :mlo.0$^{\circ} $C and a gauge pressure of 0.350 atm, (a) calculate the volume of the helium gas under these conditions.    $m^3$
(b) Calculate the temperature if the gas is compressed to precisely half the volume at a gauge pressure of 1.00 atm.    $^{\circ} $ C

  What is the pressure inside a 35.bqhu)r6se9 y 10-L container holding 105.0 kg of argon gas at 385 K)hq y1eu9r6 bs?   $ \times10^{ 8}$Pa

  A tank contains 26.0 gp;y zfeyqq 2t(7qj+at b07 d8kg of $O_2$ gas at a gauge pressure of 8.70 atm. If the oxygen is replaced by helium, how many kilograms of the latter will be needed to produce a gauge pressure of 7.00 atm?    kg He

  A hot-air balloon achieves its buoyant lift by heating the air insiyv bq, l5n7qc 8ics+o,de the balloon, which make cno 85,qqi7+,byvs cls it less dense than the air outside. Suppose the volume of a balloon is 1800 $m^3$ and the required lift is 2700 N (rough estimate of the weight of the equipment and passenger). Calculate the temperature of the air inside the balloon which will produce the required lift. Assume that the outside air temperature is 0 $^{\circ} $ C and that air is an ideal gas under these conditions. What factors limit the maximum altitude attainable by this method for a given load? (Neglect variables like wind.) $\approx$    $^{\circ} $ C(Round to the nearest integer)

  A tire is filled with air p- c*ggst-m0dmld 3n dbx:-mf 50j6ocat 15 $^{\circ} $ C to a gauge pressure of 220 kPa. If the tire reaches a temperature of 38 $^{\circ} $ C, what fraction of the original air must be removed if the original pressure of 220 kPa is to be maintained?    %

  If 61.5 L of oxygen at 18.m8yqaah v-a5 af+1 9ua xi/h0s0 $^{\circ} $ C and an absolute pressure of 2.45 atm are compressed to 48.8 L and at the same time the temperature is raised to 50.0°C, what will the new pressure be?    atm

  A helium-filled balloon escapes -zzq : b28vgckxq;zg-a child’s hand at sea level and 20.0 $^{\circ} $ C. When it reaches an altitude of 3000 m, where the temperature is 5.0 $^{\circ} $ C and the pressure is only 0.70 atm, how will its volume compare to that at sea level?    times the original volume

  Calculate the number of molecul p7a;hfh .cfz8s59 nwres / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How f lnq.363wt; -bgfrrhpkk 3a3 many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of931tph:9 wfx 1pp2a-svom bds (a) moles,    $ \times10^{22 }$ moles and (b) molecules of water in all the Earth’s oceans. Assume water covers 75% of the Earth to an average depth of 3 km. $\approx$    $ \times10^{46 }$ molecules

  A cubic box of volume 5e(xc 6rxjo( +i.1$ \times10^{ -2}m^3$ is filled with air at atmospheric pressure at 20 $^{\circ} $ C. The box is closed and heated to 180 $^{\circ} $ C. What is the net force on each side of the box?    N

  Estimate how many molecules of air ac 5xdc.6d( g2 czvt5ujre in each 2.0-L breath you inhale that were also in the last breath Galileo took. [Hint: Assume the atmospher6uvxdc 5gct jd.(z52ce is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kin4zsl/ey3+u p wetic energy of an oxygen molecule at STeluys+p3z /w4P?    $ \times10^{-21 }$ J
(b) What is the total translational kinetic energy of 2.0 mol of $O_2$ molecules at 20 $^{\circ} $ C?   $ \times10^{3 }$ J

  Calculate the rms speed of helium atoms nea7yz v53iwafx*n4u * ggr the surface of the Sun at a temperature of abou3*u4naz fx7ygw v5g* it 6000 K.    m/s

  By what factor will the rms speed of gas m* 50r8b wblebgolecules increase if the temperature is increased e lb8wbr50*b gfrom 0 $^{\circ} $ C to 100 $^{\circ} $ C?   

  A gas is at 20 $^{\circ} $ C. To what temperature must it be raised to double the rms speed of its molecules?    $^{\circ} $ C

  Twelve molecules have the following sp odhv.yeg ,oh.qm prdo9s +-:+eeds, given in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calculate the rms spev.9o+qmrhdo g .s ye-p, odh:+ed. $v_{rms}$ =    km/s

  The rms speed of moleculesi 9 q; kn7mnvak;3qc2s in a gas at 20.0 $^{\circ} $ C is to be increased by 1.0%. To what temperature must it be raised?    $^{\circ} $ C

  If the pressure of a gas is doubleh*uy7qsti3 *mz4: if)5 wwug vd while its volume is held constant, by what f w7mi3y gz*54f*ws:tqhu)i uvactor does $v_{rms}$ change?   

Show that the rms spp 4gp qso*p);/y-br gneed of molecules in a gas is given by $v_{rms}$ = $\sqrt{3P\\rho}$ where P is the pressure in the gas, and $\rho$ is the gas density.

Show that for a mixture of two gases at the same temperatumf::m6( kap+ ys7aund re, the ratio of their rmu+k nmaf6(:sdp7 y:mas speeds is equal to the inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen molecules contad3 )qrs9pa3khined in an 8.5$-m^3$ volume at 2.1 atm if the total amount of nitrogen is 1300 mol?    m/s

  Calculate (a) the rms speed of an oxygen molecule aa/rjs0 qleo h4nz*/jl vq( ;+st 0 $^{\circ} $ C    m/s
(b) determine how many times per second it would move back and forth across a 7.0-m-long room on the average, assuming it made very few collisions with other molecules.    round trips per sec

  What is the average distance betweenaou 9god( ,-j. xxc4nt nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular mass i w1)w66nw) wmemoxqp 3s 89 u in a livmeww13o)6x )wqn 6wmp ing cell at 37 $^{\circ} $ C.    m/s
(b) What would be the rms speed of a protein of molecular mass 50,000 u at 37 $^{\circ} $ C?    m/s

Show that the pressure P of a gas can bel 4.0fes, y.pr3qferx written P = $\frac(1)(3)\rho v^2$ where $\rho$ is the density of the gas and v is the rms speed of the molecules.

  The two isotopes of urafcu b /bf;;4;e85kawzj7v xh fnium, $^{235}$U and $^{238}$U (the superscripts refer to their atomic mass), can be separated by a gas-diffusion process by combining them with fluorine to make the gaseous compound UF$_6$ Calculate the ratio of the rms speeds of these molecules for the two isotopes, at constant T.   

(a) At atmospheric pressure, in what dsycufd 8 6:9hphases can $CO_2$ exist? (b) For what range of pressures and temperatures can $CO_2$ be a liquid? Refer to Fig. 13–21.

Water is in which phase when the pressure is 0.01 atm and the tempe6,cvz76 )o+ k pmhrdkzrature is (a)+kokh7)crzvdm 6pz ,6 90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (l*kk z1bquv /,approximately) if the humidity is 50% on a day when the teb/,v* zkq1k lumperature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water boils * xu j vk4w6nd34epn**v1jm vaat 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a r 7vgtsmx510wi xb)/uparticular place in the mountains is 0.72 atm, estimate the temperat/x m rxg7w05b tiv)u1sure at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partx+ edr,sda0 k mdns7/e6ra 3v)ial pressure of water is 530 Pa an70add+es,m63d)rves /xn arkd the relative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the temperature is 23) d6cb(b haiq5 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure coo9 ik y(yfak8 jw:03bihker if the water is boiling at a temperatureh a k(83jyyiwbkf0 i9: of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room ofdgl5c(s7 y g7u o;jif: volume 680$m^3$ at 25 $^{\circ} $ C is 80%, what mass of water can still evaporate from an open pan?    kg

  Air that is at its dew poin8 ;ota;nxge yzrh,va5udft3.4/ d pc+ t of 5 $^{\circ} $ C is drawn into a building where it is heated to 25. What will be the relative humidity at this temperature? Assume constant pressure of 1.0 atm. Take into account the expansion of the air.    %

  Estimate the time needed for a glycine molecul)snaieh) hut/ g(:nt;e (see Table 13–4) to diffuse a distance of hutat n eh/sni :)g);(15 $\mu m$ in water at 20$^{\circ} $ C if its concentration varies over that distance from 1 mol/$m^3$ to 0.4 mol/$m^3$ Compare this “speed” to its rms (thermal) speed. The molecular mass of glycine is about 75 u. t $\approx$    s ([color=rgba(0, 0, 0, 0.85)]Round to one decimal places) $v_{diffuse}$    $ \times10^{ -5}$ m/s
$v_{rms}$    m/s

  Oxygen diffuses from the s (lhfwxwk)8tdp0w 00y2l 1ek gurface of insects to the interior through tiny tubes called tracheae. An average trachea is about 2 mm long and has cross-sectional area of 0 wtplk10 0)khew y dfgw(l2x8$ 2\times10^{-9 } m^2$ Assuming the concentration of oxygen inside is half what it is outside in the atmosphere,
(a) show that the concentration of oxygen in the air (assume 21% is oxygen) at 20$^{\circ} $ C is about 8.7 mol/$m^3$ then $\approx$    mol/$m^3$(Round to one decimal places)
(b) calculate the diffusion rate J,    $ \times10^{-11 }$ mol/s
(c) estimate the average time for a molecule to diffuse in. Assume the diffusion constant is $ 1\times10^{-5 } m^2/s$    s

  A precise steel tape measure has been calibra qq g .c6(.lo8joh4dqz;8aww n:3lxx4gf dt6j ted at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A precise steel tape measure has been calibrated at 20auar w;eq,0 qvy,co- 7$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A Pyrex measuring cup was cali1 +yi(toc:npo brated at normal room temperature. How much error will be made in a recipe calling for 300 mL of cool water, if the water and the cup are it1(+ ycnoo: phot, at 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in a helium gas cylinder is initially 2kp)pc+-b 5ouq 8 atm. After many balloons have been blown up, the gauge pressure has decreased u5)p-o c p+qbkto 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air molecules in a room of length)qk;,cmfnz51by ku10kxr qa, 6.5 m, width 3.1 m, and height 2.5 m. A,kkqf,ybru1qk1a;zmc n x 50)ssume the temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the de3e:rvez5sz * snsity of matter is about one atom per $cm^3$ mainly hydrogen atoms, and the temperature is about 2.7 K. Calculate the rms speed of these hydrogen atoms, and the pressure (in atmospheres).$v_{rms}$ =    m/s    $ \times10^{-22 }$ atm

  The lowest pressure attainable using the best available vacuum techniu :2p/cvw2:-js )j1wwdlzhi dques is abo2 uww/cs:h1 dw i2:)zp-j ldvjut $10^{-12} N/m^2$ At such a pressure, how many molecules are there per $cm^3$ at 0$^{\circ} $C?    $\frac{molecules}{cm^3}$

  If a scuba diver fills his lungs to full cap- is*s hv.kay9acity of 5.5 L when 10 m below the surface, to what volume would his lungs expand if he quickly rose tohs.9 ias y-*kv the surface? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’s ato vhy4 :ssqh)1mosphere at a speed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this sosq 1svhh)y4: peed correspond to what temperature? (Because of this high temperature, the nose of a space vehicle must be made of special materials; indeed, part of it does vaporize, and this is seen as a bright blaze upon reentry.)    K

  The temperature of an ideal gas is increased from 11 f t4llpv*x(z.0$^{\circ} $C to 360$^{\circ} $C while the volume and the number of moles stay constant. By what factor does the pressure change? By what factor does $v_{rms}$ change?$\frac{P_2}{P_1}$ =    $\frac{(v_{rms})_2}{(v_{rms})_1}$ =   

  A house has a volume of)loqnt wu4 y2+ 770m$^2$ (a) What is the total mass of air inside the house at 20$^{\circ} $C?    kg
(b) If the temperature drops to -10$^{\circ} $C what mass of air enters or leaves the house?    kg

  From the known value of atmospheric prfolnsjvbw+ l) 1pow030d i v2.essure at the surface of the Earth, estimate the total number of air molecules in the Earth’s atmosphej30vwi0 2+ld wpofs bln)1vo. re.    $ \times10^{44 }$ molecules

  What is the rms speed of nh wq9:q(u,;(pz k z;g jl+brdwitrogen molecules contained in a 7.6$-m^3$ volume at 4.2 atm if the total amount of nitrogen is 1800 mol?    m/s

  A standard cylinder of oxygen used in a hospital has gauge pressure = 2000 prqn ys 100w+ioarbf6bgj5(+um e8 e :gsi (13,800 kPw0eg+asy g fr68bnimboe+:0(uj15r q a) and at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of 5-+ l zrc nwbz-5no1w/hm8)qdw 2mwea liquid mercury at 0$^{\circ} $C. (a) If the temperature is raised to 25$^{\circ} $C, will the cube float higher or lower in the mercury? ----待选择----lowerheigher 
(b) By what percent will the fraction of volume submerged change?    %

  The density of gasoline/e wz;446jaheb bwg*o at 0$^{\circ} $C is 0.68$ \times10^{3 }kg/m^3$ What is the density on a hot day, when the temperature is 38$^{\circ} $C?    kg/$m^3$
What is the percentage change?    %

  If a steel band were to fit snugly around the Earth’s equa+ ih2n4k93qz8tl t unytor at 25$^{\circ} $C, but then was heated to 45$^{\circ} $C, how high above the Earth would the band be (assume equal everywhere)?    m

  A brass lid screws tightly onto a glass jar 7a ahbs0g/2 dfhvm( l0at 20$^{\circ} $C. To help open the jar, it can be placed into a bath of hot water. After this treatment, the temperatures of the lid and the jar are both 60$^{\circ} $C. The inside diameter of the lid is 8.0 cm at 20$^{\circ} $C. Find the size of the gap (difference in radius) that develops by this procedure.    cm

  The first length standard, adopted inb8*-begqmn y9rq n9w - the 18$^{th}$ century, was a platinum bar with two very fine marks separated by what was defined to be exactly 1 m. If this standard bar was to be accurate to within $\pm1.0 \mu m$ how carefully would the trustees have needed to control the temperature? The coefficient of linear expansion for platinum is $ 9\times10^{ -6}C/^{-1}$. $\pm$ =    C$^{\circ} $

  A scuba tank, when fully charged, has a pressure of 10/ 7)g aj;uxdv2 v1gtbmir7 +ykwdx o8)5 rfjs95 atm at 20$^{\circ} $C. The volume of the tank is 11.3 L.
(a) What would the volume of the air be at 1.00 atm and at the same temperature?    L
(b) Before entering the water, a person consumes 2.0 L of air in each breath, and breathes 12 times a minute. At this rate, how long would the tank last?    min
(c) At a depth of 20.0 m of sea water and temperature of 10$^{\circ} $C, how long would the same tank last assuming the breathing rate does not change?    min

  The escape speed from t0p6-n:jpshjh0naq(-f d ds i0 b3hxv 8he Earth is $ 1.12\times10^{4 } m/s$ so a gas molecule travelling away from Earth near the outer boundary of the Earth’s atmosphere would, at this speed, be able to escape from the Earth’s gravitational field. At what temperature is the average speed of
(a) oxygen molecules,    $ \times10^{5 }$K
(b) helium atoms equal to $ 1.12\times10^{4 } m/s$    $ \times10^{4}$K
(c) Can you see why our atmosphere contains oxygen but not helium?

  A 1.0-kg trash-can lid is suspended against gravity by w:0 4j(k sw6iwainq2ktennis balls thrown vertically upward at it. How many tennis balls per second must rebound from the lid elastically, assuming they have a mass of 0.060 kg and are 6w 4 w:iqs2knkaw(i0j thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter (spherical)c h91v(qs-v wg bubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the air behaves as a perfect gas. How large is the bubble when it reaches thg vcw9-1vhsq(e surface?    cm

  Calculate the total water vapor pressure in tr+t:u::q0 w md s78yr qw fd(xtp;(tfthe air on the following two days: yqu :s(t8f( wdw;rfrt 7+mp0q:t:dt x
(a) a hot summer day, with the temperature 30$^{\circ} $C and the relative humidity at 40%;    Pa
(b) a cold winter day, with the temperature 5$^{\circ} $C and the relative humidity at 80%.    Pa

  A sauna has 7$m^3$ of air volume, and the temperature is 90$^{\circ} $C. The air is perfectly dry. How much water (in kg) should be evaporated if we want to increase the relative humidity from 0% to 10%? (See Table 13–3.)    kg

  Estimate the percent difference in the density of iron at S9fk(b9( y bdyaTP, and when it is a solid deep in the Earth wb y9a yfd9k(b(here the temperature is 2000$^{\circ} $C and under 5000 atm of pressure. Assume the bulk modulus (90$\times 10^9N/m^2$) and the coefficient of volume expansion do not vary with temperature and are the same as at STP.    %  ----待选择----decreaseincrease 

(a) Use the ideal gas law to show that, for an ideal gas at constant press zqdg 3+ay38*i7zpqqjure, the coefficientyzj8i7qq p* agqd33+ z of volume expansion is equal to $\beta$ = 1/T where T is the temperature in kelvins. Compare to Table 13–1 for gases at T = 293K (b) Show that the bulk modulus (Section 9–5) for an ideal gas held at constant temperature is B = P where P is the pressure.

  In humid climates, people constantly ko3fs yrj(13 pdehumidify their cellars to prevent rot and mildew. If the ce3 oy3(fkrpsj 1llar in a house (kept at 20$^{\circ} $C) has 95 $m^2$ of floor space and a ceiling height of 2.8 m, what is the mass of water that must be removed from it to drop the humidity from 95% to a more reasonable 30%?    kg