Which has more atoms: 1 kg of iron or 1 kg of aluminum? S2 xnit0yb2ls* ee the periodic table or y x2lsi b*2n0tAppendix B.

Name several properties of materialr30, --ke,doqek.0oeg jgp gbbss - +ws that could be exploited to make a thermometeg,b+ssr,bko0k0 d .e3g epj- -qow-egr.

Which is larger, 1 C) wf/(+arkdy *j+4 md tmghd;d $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with (qf 7z y8ji6m oj-k9ze, v(afwsystem B, but B is not in thermal equilibrium with system C, w,j mf6fqie z8v -9az k(oj(y7what can you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to r/ k 4frgr4k* eboy4z7a strip of iron. When heated, the strip will bend. Which metal will be on the outside orgk4b474 /yorrk *fe zf 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 coefficient of linear expansionx+r60jh n8:tzjo)y4 4 ty vod0wtu:xt $\alpha$ 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 dzcc6r *qcv* kn8k17;yy- eetaiagram of a simple thermostat used to control a furnace (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 liquid mercury that conducts electricity when it c 8krvy7t*kzac ec* ne;16-qc yan 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 thec6)p.6j mj-5p kzoht6bun 98 rkhanr1 shape of a U. Why?b hnu-8rjrp.5c m16pn69jz)t h6akok

A flat, uniform cylinderbrgce;7 qk99k of lead 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 pblzrbm8(m zh+ ai--:g laced in a hot tub of water, the mercury initially descends a bit and then rises. Exmgl +:a- zmzb b8rh-(iplain.

A glass container may break if one part of it is heate69loaccx.zaz 5g/p s -d or cooled more rapidly th5/agclxz6p-aoz9 s.can adjacent parts. Explain.

The principal virtue of Pyrex glas;;- 0zkb7c yjyhq)b ids is that its coefficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Expibk -qdy);yz07jb ;chlain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurate aghe, 7 bes/-qdt 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 bulge so badly the cad,lfi, 9oj-9 a tr1j b-ht*cdin will not j lj,9,ihi 9-db-ct*t1odrafstand up. What has happened?

When a gas is rapidly compressed (say, by pushing dowli n13 odtry7ui44+vu n a piston), its temperature increases. When a gas expands against a piston, it cools. Explain these c+4nytur7o31luiv d i4hanges 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 aluminumbe3w fgcz1pxr+0pkziq 7 e;89 sphere submerged in water increase or decrease if the temperature is increased f0pkrpz7xeg 9 cq3+wz efi; b81rom 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kino9 sad1b4,*s h2fu zaaetic theory and the relation between average kinetic energy and thesz2oa4d 1 9h ,s*auafb absolute temperature.

Explain in words how Gawajo:z-24*p,t pvddn ,yjgg, y-Lussac’s law follows from kinetic theory.

As you go higher in the lor7f e0m6kw6 5klg4 kEarth’s atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed an object must have llk7f)u )1( :+l.l auctnzctkaoa j+(to leave the Earth and neveaku7alt.)ul(lz:cnt(f o +jkcl 1+ )ar 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 the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at roomxr9zj47q;4lpw 6q z jy temperature. What can you infer about the molecular properties of one relative ty 4jwzq 94 6rljx7q;zpo the other?

Explain why a hot humid day is far more uncomfortable than a hot dry ekb/k1hll14 o day at the same temperatkoebl1 1kh l4/ure.

Is it possible to boil water at room temperature (2*aeh :09g* ngo5 fxhtd0 $^{\circ} $ C) without heating it? Explain.

Consider two days whenrc;pa,y.m 2nmmdap0bx, z 16qa4z7mm the air temperature is the same but the humidity is different. Which is more dense, the dry air omx1dqmmzbyp r2 7ma,zca60n4a.m p, ;r the humid air at the same T? Explain.

Explain why it is dangerous to open the radi83o:tiz qqy0 kator cap of an overheated automobile engine.z3:08to yqkiq

Why does exhaled air appear as a litt7rsoupeqpv8 ri32q /0ht g3 2cle white cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram copper penc9xi c( 1jmp;eny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compara9zk(/y)f scpe to the number in a silver ring of t(p)k fcs/9 yazhe same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be8 g-w os .jeqbxj;)0+fjp,l zs wjv,3a::mxke 68°F. What is this on the Celsius scale?o38l : 0+j jv x.efapjszs,qj-;w:bkwm e,g) x   $^{\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 lq- uigo/y(kty95 bem *owest 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 thetu3is1 tw6-6r4mi jjf+; yonmrmometer, the alcohol column has length 11.82 cm at 0.0i m3f m njyt6s+wti-41;jo 6ru $^{\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 slatn*go;(c: q-ye5:dh +x5j kcl6ahkrwfg (t)ibs 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) isp6f1bw tr :(go+ blpg3 built of wrought iron approximately 300 m tall. Estimate how much its height changes between Jg+rwogpl b1:ftp3( 6 buly (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 tr-rsk/rz. h h;;y;)xq61sfs d/ndlr shan the rivet hole are often used a1r- ;q.r/x s;dr s r;h6zh)k s/flndsynd the rivet is cooled (usually in dry ice) before it is placed in the hole. A steel 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 jhdw(j3x v+qu xj-sf k8k),h;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 will be b*yurdfz -/+ hits change in volume if it is heated zbu ryhd*-f/+from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to mvl z1io ,.12rkyq+c4 kjta,b8wls*b the brim with 350.0 mL of water at 100.0$^{\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 wpo9na7 wq, +wo8sm 3l3ptja,.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 p;y:8tqez) oq 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 (mzoad a( i(x; -+-7 r w2/whzzscmcwwa long, narrow vessel so it can expand in essentially one direction only, show that the effec( rzwa/ x(-7amwzih-wz ccd(2+om ;swtive coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the d k nlz(n0h t/oy9qf td(8t2etjd y40;lensity $\rho$ 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 ofc(aok s; 9r 9hj-dcsd( linear expansion d9(odk;rsc j-ch9sa ($\alpha$ 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 sz .+lv8*i ss-vck 9lmgolid, $\beta$ = 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 brass and keeps perfect ti8wvk;ogr :; p4 jeg3zhme at 17 j3:po;gh ez4 wvk;8r g$^{\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 has an inside diameter of 0. ;pz;) kkds: t4j2t3gfy9npjr140 mm. The bulb has a volumzprkdkjg tf;:24t)3y 9 sj; pne 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 cylindricyabz 5owgt5:4 17zohbal wheel of radius 0.41 m is rotating about its axle on frictionless bearinab5h4 zw:z5o oyb1gt 7gs 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 le 3+ h *0owqo3nroqb yiiv1w6*jngth when at 15°C. How much stress is required to keep it at this length if the temperature 0w163ono rhoy3w +*q vji* qbiincreases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel Iozkxx198l84bvysf c;d dm3u/-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 cm atpcu eoo jnuc-b1.8n/+ 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 )7kwp*9b- jkz 0x(qq s.azdxmthe 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 Fahrenheit scale?5kdu8po* w9/kd nf ot)mp qd.)    $^{\circ} $ F

  Typical temperatures in th9tce a8-erl9w vd*3vpe interior 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 t e1f-poll-*56 qblbgengine, air at atmospheric pressure and a temperature of- o16l flg*pb5qet-l b about 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 STP us 1873eyw70 lyztdribying the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of gs8/v u0z)uk4x aan/.or07kxvi0 rjlnitrogen ($N_2$) 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 contain.9xrrk1c;cl, x( 8ibey s v/qms 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 isbm +5hpepf:+ x3e g5lauk(g6 y 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 10ro zh(;a) ,xcm5.0 kg of argon gas at 385 Ko am,z xch;r()?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg c:8. njs9 wrudof $O_2$ 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 inside the b6 :,v dz5et+keoa.z5 :rznvp fmawa )+alloon, which makes it less dense than the airzawd +a5 tva5n)pvfe zro:6 me. k,:z+ 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 withaqeho0 6nq0w9 ,j .6 bzedaue-nu2,lx air at 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.z+m858i cs1hdjwls2j0 $^{\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 a child’s h88*5 ct1mp powp;a mqhand 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 / cbdw9x0 v3lnuhkab(9v. 3 yf-og. x p*$m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How many molecules? rj8iw6;s6rh t zdz+l6lwv r6,g ) x:zg   mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) moless5g)zsgbe p 8,,    $ \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 51i o6v, zg e*xeu7mcct77zlm:.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 are in each 2.0-L breath you inhale that wep) 8wg:4z lmhlre also in the lasmw4lgl 8:ph z)t 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 molecule1 1q5m+b jkw9fzbp9pn at STP?p1b k99pfjb1nm +q5wz    $ \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 ato(itluk(.3j opk;u qpuc /3l u:ms near the surface of the Sun at a temperature of abok. / :;q3i(3 uoutcl(pupuk jlut 6000 K.    m/s

  By what factor will the rms speed of gas molecules increase if the t1a qp( u7r*8ymllhna n ;8pz*uhnct6- emperature is iam c7uu *n(p8qhzy -ll8th6*n 1r;p anncreased 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,,ay5,-hi(ze qv kd.i k given in units of km/s: 6, 2, 4, 6, 0, ke k.vqa,y( di5,iz-h4, 1, 8, 5, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecuatvf-)*v2d xu3fs z*eles 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 doubled while its volume is held constadl01wbqd+ o x-nt, by what factor +b xlwd01 d-oqdoes $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is giwe6) bx(m z62 ombnz(sven 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 temperature, the ratio ofp; gj s6nnih:j r4 qb5dfptmshja y4+)-8nl)7 their rmsjr ms+)nq48 gh5yd ; h j-j4s7tnn:aipbf)p6l speeds is equal to the inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen molecule:vbm55(4 w2 :eivywm.w 0bnx, s(dxevxs j0zhs contained 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 sp4pks4vhu.6kdm4r h :q eed 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 distance betwee-8.htx lqyi6; juuf.xzh 6i j.n nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of y5,rtbwuz ,quas4 m-)an amino acid whose molecular mass is 89 u in a living cell atb5 ru tqu,z)m4, wyas- 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 be written q 3i*e1pwl rqm:p94v9cfh8ja 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 uranivoddb1yol+ft,f)c 0 5um, $^{235}$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 pz8:n:g7bf0a9t*7q 3q;bsz aiuia gkwhases 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 aevk*pual 5* 7snd the temperature is (a) 90 us5a kelp v*7*$^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew pointugh ii/m.8c6xz ;d3 lr (approximately) if the humidity is 50% on a day when the temperature is xrih;/ 86zl udg3.mic25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water boils at ;j* r6bvcwkkznf we) w/zc6e5z9 j(3m90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is .qgwm;h5;- 4 jkaecrt0.72 atm, estimate qk ;mh5.wcrg4-etj;a the temperature at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperatu)lwev 6g8i .b;v 6c+lix-dppm;cr8elre on a day when the partial pressure of water is 530 Pa and the relat;v88mlc.)d;veli ibr-wpe+ l 66px gcive humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the te7h :tss9mpridfl85f 3mperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressurxwqnvb :s8m-ahi.7g7e cooker if the water is boiling at a temp isqhnm:xagv.78b -7werature of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a roost(dvay 0 7pg6m of 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 p(, syjpy--bai/7p (bi pe a;6qc b.xsw3i1ozvoint 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 molecule (see Table 13–4) +oi-m7 rc;gmp..h yjhto diffuse a di r+ m. mc-7ihjpy.hg;ostance 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 surface of insects to the interior through tinpberh4 k1hunk/nz/ a 3-inn 6:si )is3y tubes called tracheae. An average trachea is about 2 4e)z1sas -h/nii 6i: 3/nnhnukbp3 rkmm 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 has been c mbtkhl0d 5(czt3k(c; cs qma)m7d- ta( k6l3zalibrated 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 u;3m4+ w2 sadqrrg ld*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 Pyrex measuring cup was calibrated at normal room temperature. How muc3iintum f xu5 )4.q:obh error will mxf3 uu n.5:t4ib)q iobe made 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 initially 28 atm. Afte 0*hw7jnktmb/8 w, hjrx9cxn:cg+s 1er many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of the original gas remains in the cylinder? :ct sc/ew,jrx89n 1*n +wbhkh70jgmx  

  Estimate the number of air molecut7ln uu;espu-7c djzq1uz28yu)3a) w qf-)sqles in a room of length 6.5 m, width 3.1 m, and height 2.5 m. Assume the temperatureu--uy8wcf7qt;)1uq) e zlq2 nzus) udaj 7p3s is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is aboupwjyi 4bu7oi2)d 2r/ 8ohynqbl.s c d8e98 q3yt 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 t/eo *y+w1a addhe best available vacuum techniques is aboutdwoe/a *+a1yd $10^{-12} N/m^2$ 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 w63j 0kw/vmex c/o kc 6(r6ahz:no4t vfull capacity of 5.5 L when 10 m below the surface, to what volume would his lungs expand if he quickly rose to the surface? Is this advisable? mz4co c(x an/0k/jerv:vh k3o6t6 w 6w   L

  A space vehicle returning from the Moon ente*wm ek :t8sks5rs 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 nose of a space vehicle must be made 8*5k:mssktw e 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 increaseds6g 6ctg 2dsw7u/vsm ysq1+5b 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 rvh/s x3ht9jofg 0s2( 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 pressurefuqyj0)me: rvj ,j5 2f at the surface of the Earth, estimate the total number of air molecules in t05mfejf q yr,v )jj2:uhe Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed.*w;(mozet ptbn +(ai of nitrogen 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 zz;a+)rlm: indmxb :6has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, nzx:6b +m lidr:)amz;measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liquid mercuzq 9 :os(crn.xry 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 ate +8zo:ly 04ons aq0ei 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 equatofubfxdbzj 4u b/,u) 1z:h )b*. ywv84zzn+zr dr 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 jaz w-mu.x)ok4mr 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, adopted mon9w19tw tk xrhc* +v9to; h8in 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 pxb9 mqjfku :h- 1q183otd/re yressure 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 the Earth i5uh s7*nhtvv1s $ 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 tennis balls thrown verw:k-tgw 1qu,7+7ckx/ cpqwli tically 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 areg l7,7/ :ixkwc+-pq tq1 cuwkw thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter (spherical) bubbltx b/g5bqamx2rmh1 :,e of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the:maq 1/ 5t2hmrx,gbbx air behaves as a perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure in the a(k jjm2. 6dwsz/e/ch eir on the following two days: ( ckjs 2m .w/jedhz6/e
(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, and when it iz/e y+ mt. pzytb/e(m8s a solid deep in thte(zypzbmt /y/.em +8e Earth where 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 i 5-d syo 5lcjbp:,nsdm06(o ian ideal gas at constant pressure, the coefficpni :m-is,(yb d6sdc 0 oj55olient 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 dehumidify their cellars to pr m*,3fe8zjxja3+ svw vevent rot and mildew. If the cellar in a j 3*javm zef+ws,x3v8house (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