Which has more atoms: 1 1x9/b h2vsmso8o+g x l5l4ccf0izb *ikg of iron or 1 kg of aluminum? See the periodic table or Appen/gi ob19miv2zl4*bh50s l8 ocxx+ scfdix B.

Name several properties of materials that coux l62fxnvdy/ bl -au1*ld be exploited to make a thermometer1y- bxvlla2nd6 f u/x*.

Which is larger, 1 C+u9yzo/ jd i:e $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, b1mu bld v, ip5.scyi*+ut B is not in thermal equilibrium with system C, what can you say +p .ms1dv, ibci*u5y labout the temperatures of A, B, and C?

A flat bimetallic strip dxstyvgf4u4*q- ge u c/6*y( wconsists of aluminum riveted to a strip of iron. When heated, the strip will bend. Which mex-4sq/ u gwtv(ey*6 d4*cygfu tal will be on the outside of the curve? [Hint: See Table 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; moya9oy. mrd ew1-i-*b-x zvfficient 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 fvmort89xf1 t/ r3rd y67p9pfnurnace (or other heating or coom89pxor/ 197 rytf6dnt3pfr vling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch is a glass vessel containing liquid 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 havwp5paw(b i i i,5z-a6se a section in the shape of i5awzb, -6as i5ipw(pa U. Why?

A flat, uniform cylinder of m qiuk/+dk7ti3vq5 tgxjwz cb7gx8lb 3 t+2+5lead floats in mercury at 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 in a hq ongmtr94+on m*vb5gja 5+ jmo/.d5c ot tub of water, the mercury v5b9go5r+nooj5 j./tnqm *m4 ad c+m ginitially descends a bit and then rises. Explain.

A glass container may brealz) sty2 z/*wzk if one part of it is heated or cooled more rapidly than z*2l) z stwyz/adjacent parts. Explain.

The principal virtue of Pyrex glass is that its coefficient kn7 mkwd w,s94r,dj9c of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the i kd9,7 dsj9r,nwm 4ckwncreased heat resistance of Pyrex.

Will a grandfather cloh4xp0g )gp6hap , i,1tx.dkbock, accurate at 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 will cause its bottom and top to bulg3m. dmg-ori(ke so badly the can will not stand up. What has happened-d(kmmi o.r3g ?

When a gas is rapidly compre8jz juk n/)e:zvm w8e;ssed (say, by pushing down a piston), its temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperature using the kinetic theory, in kz) vnu/j;zje 8m:w e8particular noting what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force on an aluminum sphere submerged in water increasyt 9wltyibu1 3yof9 4 8k9d8sze or decrease if the temperaturfyydw1ly z99kt3b uoi8s894t e is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theorsaks:(aqu j6 +y and the relation bet js:6 +sk(uaaqween average kinetic energy and the absolute temperature.

Explain in words how Gay-Lussac’s law foll 0l.ju xgs ry6p g6pu;oz6sz+4xvye2(ows from kinetic theory.

As you go higher in the Earth0 tc-w0pnz 6e x0:gnqik8mn:jo , ;bfg’s atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed 30qo-isl lf.p r q a 0vpb3g-q8-g.fvian object must have to leave the Earth and never return. The escape velocity for the Moon is about g0qlsf .iq--gp8o.vq3l - rf3aibpv0 one-fifth what it is for the Earth due to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at room temperatgm kswg17:j-+ttp -sture. What can you infer about the molecular properties of gt-spmt wt-g s:1k +7jone relative to the other?

Explain why a hot huue2u47 6eil+.p6vr r ysh91vaoa dky 2mid day is far more uncomfortable than a hot dry day at the same tema.lvo6r2 9y 4 puae6d 27iu+ r1esykhvperature.

Is it possible to boil water at room temperkk2cs-c3:b nwatg/spn*v.* ys0:m oc ature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is th 4x+2yk(v urpesyv.3hpbk1 d:e same but the humidity is different. Which .:r 4k+x dkuyvvpb (s y3he2p1is more dense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap of an overheated aut7-4 pmtz5yi1 do 7pohiomobile enginepioz7mo ti5py-d4 7h 1.

Why does exhaled air appear as a little wfy 3 lfzu1y+s1hite cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.x pm68 . 8cgvs.raed2r4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a x bk sqec;-om4lais5dnl4 e82 vw0 d/026.5-gram gold ring compare to the number in a silxeqsc w54v 80ms4on2a i/kddl;le0b -ver ring of the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is -o/) 2mhzyd uh5kc *u3j.es:2kfk o hsthis on the Celsius scale? 3omk/:kh dzsce2j-h y*huf 5)os.u2 k   $^{\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 and lowest tempem;d zwaxbn+ 3b6n2g 0gratures 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 a 5 n3rtn7 6hiiq8t:voqlcohol column has length 11.82 cm at 0.0o:nnq vi37 ht5rq6 ti8 $^{\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 buhk: ye4yjwn14p6v 1)j9ld i sbilt of slabs 12 m 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 2pomu 7uq+7jvq:xx mk9e7*meof wrought iron approximately 300 m tall. Estimate how much its heightx7mj2u7eq+x*: pmkm vu qeo 97 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 r n- n-4/bjybryebilqdw,n273 ivet hole are often used and the rivet is cooled (usually in dry ice) before it is placed in the hole. A steel rilidw , nrjn e-3y /7n2by-qbb4vet 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 2pr 1qx9sog(aevoj7x+z lk) )at 4 $^{\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 diameter. What willavllg-2g64 ln, ljc+o be its change in volume if it is hl4n2 vajl-lg o6 gcl,+eated from 30 $^{\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 100.0kq; q6 bm7znf66(shktcua m-l+1sy hy 3z.ma8$^{\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 55cbt vvf 3sr 4t41gjv), +(poaj.50 mL of water at 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 made of iron. At 20 h38* hd bctiv77ste 9 5jujhf)$^{\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 expand in essentiallfe xkb8:mw:m s24e3qkkm.h /ey one direction only, show that the effective coefficient of linear expansion is approximatk3e4.m: exw k/ e fhms8kb:2mqely equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the d6*;n jlge/x kpensity $\rho$ 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 r)vpk+kgrj*chr. q wqk8- r v;3.7radof linear expans .k.3vkrr*8p-qaq7wcrkg+h ;rr)v d jion $\alpha$ 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 isotrop qr3;8ciqu vpe,/;xyt ic solid, $\beta$ = 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 made of iodh2od 6;4fcbrass and keeps perfect time at 17cd64iodh;o f 2 $^{\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 thermometer haskd di:ewxe.ydh70;c9 an inside diameter of 0.140 mm. The bulb has a volume of 0.255 cdi kwxed7 d.ey;:9 0h$cm^3$ 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 abokbu6;emk x*,rcr 7w5- 8dv edgut its axle on7kcubw x,r kge-v*d5 e;m86rd 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 the desired length when at 15°C. How much stres +1(qo9*dpuzpe erwvl .;n4pds is required to keep it at thisdvp9+*(;1e. eulzp rodq4pwn length if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steuwdz4 s4,1sgba q.ri z8/dvm3el I-beam of 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 134.122 a( )w kwx93zbqcm 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 temperatures on the Kqe5rmv8; b)qk elvin 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 ammwq(( ns9+1otf l8/ jf rafl3j(;qmFahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sz nv ip a,kk+0a(8drp5ld-/g( az/l wxun 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 combuiaf 49gc 4;vecab t7m;7:r bhvstion engine, air at atmospheric pressure and a temperature of aboutacerb:;g 4iv;b 97v4ahm 7f tc 20$^{\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 of oxygen at 3,6 0e5jefrvi )v:qos+a i: zzrwp n(cSTP using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of p 6azzh5 y3z+xnitrogen ($N_2$) 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 contains 18.5 kg ql+anz/fdy0 ( 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 ii39zcg:fem -/xxk0w u t(lso-s at 10.0$^{\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 35.0-L container holding 105.0 kg of argon *odkhsv30k m1gas at 385 3*0vmhsk1dk o K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 zcjv*j -lx n81kg 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 buoy7bz a.ss,s5h cant lift by heating the air inside the balloon, which makes it less dense than the air outsid5.ss,z hcsa 7be. 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 atb+jc km31/mzr/o p(tt 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)u2k 5.+qs ce /mbaq l7vi*f3bhcy)sb 18.0 $^{\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 escapecp 6v9 psie0x6 )uqli/s 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 molecules / w42foem iw:f9$m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water arrupwyg48vd6flk9)s *u lh(r y vvr/: 0e there in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) m7 j1n)bkk yj2dk44/c 5c)mzv6b xie pcoles,    $ \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 5.1b i 5mmm/p0yb;$ \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 are in each 2.0-L breath you i:y a:il 1)uqg7bo3qnlnhale that were also in the last qbgloy7 :1l:3u)nai q breath Galileo took. [Hint: Assume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of an oxygen molecura4kfq057qe m le at ST075mrkq fea q4P?    $ \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 near the surfb*zowhwy)9/m o w9 0- z, dhuofv*f)imace of the Sun at a temperature of about 6000 K. omvm yoiwffb z* -wu* )o0hh,)9/d wz9   m/s

  By what factor will the rms speed of gas molecules increase if the temperature a. hpk8tkv91 6f-8sz7bvkwf jis ik 6vs k7z1vjkbh 8ft.pw 98fa-ncreased from 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 speeds, given in units of kmlkv0:j bmyclr80* 3qx/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, aq 0mvbry*l:0 jlx3k8cnd 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a3f+ zg geir25mm j+fr- 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 doubled while its volume is held constant, bya r2-fak:73y 5 grocl)l*t6jzh1vwi n what fact*cz y 7j2kirafvl5t:1woa3rh6lg n)-or does $v_{rms}$ change?   

Show that the rms speed ofg2asrc4b ) t: +ypuqa: 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 tempegnt (:lrk;vjvvgxn*- tu0:;yrature, the ratio of their rms sp;(0;:ku* vjxnry- vtglg:v tneeds is equal to the inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen molecules containeftofb6wn* yo 6+mk 4r5d 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 speekfo -:nd* gwc ,6v4 j)ez:hopv7*crzx d of an oxygen molecule at 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 d/ 3a5ddpc )rm4 8apxhsistance between nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose q -dcq,;srt*z4r 5hg0ext z )hmolecular mass is 89 u in a living cell at r z ,qx 4etgqcs;d-htz5r*0h)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 y 2mzwz :,*mm i/lf7dy f z6lbj5)/ptoa gas can be 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 uranium, jrju +pbszph +ht5ik87,e+ k)$^{235}$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, ipt e0l bpl,v:6)c8ujf:r+ rgdn what phases 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 an/nihnp7v(,td f 4fkhb4b6gk (5 pr1dfd the temperature is (a)bthfrffn4/ dhk,7n(g p46kb vd(ip51 90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (qr7 sofz n,.n87zs ,yh)t ,owoapproximately) if the humidity is 50% on a day when the temperature h7 r y8,7f ,.sz,oosnwq)zo tnis 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water. bqvahgz)w) 0 boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountainf;u)l mr1kf;a s is 0.72 atm, estimate the tefalmk;ru) ;1fmperature at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of wat,+ln bc /l9 ;a jsqyhaue hr.)q7+my)fer is 530 Pa and the relative humidity i aua h)flsq. b;mclqny e7/ +r9y,)+jhs 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial prho)apwn40, g-uh wje7 essure of water on a day when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressuk wkd5gz:dphz c (n6 w q6;c.-*w4.nmjpxc;jqre cooker if the water is boiling at a temperature of 120w.j56z6j.nkm d w;-g wk* (zc xqc4 hd:p;pnqc $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room o 1ij o jt0vp/; *ovj84zdv3zkgf 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 df7nj ysddt/4/ew point 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 gly32j7po/o mxki wdn:b.cine molecule (see Table 13–4) to diffuse a dinb3 /dox.k: om7w ipj2stance of 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 snw ,f s*+. hrtfw9zfz/urface of insects to the interior through tiny tubes called/nrz +*,9t.zwffwhfs tracheae. An average trachea is about 2 mm long and has cross-sectional area of $ 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 hasdyw2/exz . *dn puua;/ been calibrated 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-o(- dwdjtmtaprl(q ,( o9yiv;u6 k*n 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 Pyrex measuring cup was cali 7)zcyq s,ltm/brated at normal room temperature. How much error will be madz tqsm lc/7y,)e in a recipe calling for 300 mL of cool water, if the water and the cup are hot, 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 ini /ktw8/tgy 9 (hp-swnltially 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of the (wtpg/ tn l-9ws/ k8yhoriginal gas remains in the cylinder?   

  Estimate the number of air molecules in a room of length 6.5 m, wa14)myzy g l77;b*loqco ig/hidth 3.1 m, and heigh) 7co 1oia7qm b; yz*/lyglhg4t 2.5 m. Assume the temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is about one atom udlus2fafrw og*b4;k 4;*l ;zper $cm^3$ 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 techniquen8g :hs1b(kei0rq,jts is aboub n(,kers1 itq0:jgh8t $10^{-12} N/m^2$ 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 capacity9z i;hqqsm55 a of 5.5 L when 10 m below the surface, to what volume would his lungs exp;5q5a hqs 9zimand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Mob)fybg . z;0omon enters Earth’s atmosphere at a speed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this speed correspond to what temperature? (Because of this high temperature, the no 0zf gym);b.obse 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 idea 8p*:lo)x gmlal gas is increased from 110$^{\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 k w9(dt9d4 eatefx2,c 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 pressure at the surq4d+a c- l ph-tvssm+ fl55k5kface of the Earth, estimate the total number o5hvk slp5t+s4k- lmqfc -+5d af air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of niy *c3 :;kgly rmte n4l/+wr.ietrogen 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 vmsp ,b,2v zw-nb- uio-;yh3b6. jwhrgauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmospherici;-2upybh ,whrv jnw3-zm,bb .- 6ovs pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of li snbp4jx(8(qeegyv6 / quid 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 p g *gne**rxj:nu;o b9k/ b6wpat 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 equ lh3 *uox84mf;bnk8 7+zc sauzator 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 qdv b)3 5suitb3f.tu8 p+(vijonto a glass jar at 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,hp6+ws;s+ e 8drj e;ol adopted in 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 a1dgnoch4v )fcd;; s i5 a-qcvv/+iee3 pressure of 195 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 thd+6; luj vv:ie5urkbjq+b ; a9e 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 suspd6k)m 74r jwhtended against gravity by tennis 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 thrown at 12m/dt7kwjh64 r m)s   balls/s

  A scuba diver releases a 3.00-cm-diameter (spherical) bubble of air fromf tnb5+tf1gri 3( s5x7zbzxf6 a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the air behaves xgtsz53 16(fxn+z7rtfibf b5 as a perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure in the air on the following two days: a*+b;n6 +p.p t h.mgm yntd4, +phfppv bv; mhtpfg+yp*ptd6 .+.4p+h an,mpn
(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 STP,+-dvw px(rl)0kl7kz f and when it is a solid deep in the Earth where the tempe) x0r vpk (lf+lw-zk7drature 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 cqr*+*n jvi 1g)l0mczbonstant pressure, the coefficient of vo*b g+mnzcri1lj)q*v 0lume 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 deh+7v ;w jmi(birumidify their cellars to prevent rot and mildew. If the cellar in a house (k j(m;7 i+bwivrept 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