Which has more atoms: 1 kg of 9l hj:g *;suwc8j q8y em;eyk-iron or 1 kg of aluminum? See the periodic table or Ay:*ue syhek 8q m-c 9wg;;8ljjppendix B.

Name several properties of materxsn (1yo.+ 2 6zmshvhaials that could be exploited to make a thermometey.ms6xhs+h n2vz 1o(ar.

Which is larger, 1 C5 i:0e l*kz;hvjvo.kn6 eabgj kuk453 $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, jo;y3w4 /wa xsq+p:ga but B is not in thermal equilibrium with system C, what can 34oa +;jpwg aqw/x: ysyou say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to a strip of iron. Whe0 bblm)w nqtcq(4 p,;pn heated, the strip will bend. Which metal will be on the outsp)qtwpb,qn ;0(blc4mide 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 coefficiegqd.0odslf8 ohyb . 8/nt 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 j ytb5gv4jk r6v4v m.,simple thermostat used to control a furnace (ov.m tv,5b 4jg6rk4j vyr 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 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 en.t. r/ b huk2o-ka/kotds often have a section in the shape of a/-k2bt kto/hukra.o . U. Why?

A flat, uniform cylinder of lead float))6t vik6v 5)qwlzmfn ft:nm6s 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 ho,v-9 yttbue p)t tub of water, the mercurytyb -u9pve,)t initially descends a bit and then rises. Explain.

A glass container may break if one part of i 0qzeqe6(ia7wrohq+ +b6rj e )t is heated or cooled more rapidly than adjacent pareeae6 q(76o +wjir +bqhqr)z0 ts. Explain.

The principal virtue of Pyrex glass is that its coeflfmd e 2v)q 7fbxfljmr8u,(+, ficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives bme, fu)7 +mf(8 fql2jdvl rx,rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurate at d l (e:xfqs8v6n-,xbj 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 j24e jdppv( wlyi1g l1g4o;q8 its bottom and top to bulge so badly the can will not plpw441 ye 82qgg1ojdl;j v(i stand up. What has happened?

When a gas is rapidly compressed (say, by pushing d wvu.jhz 43.dlown a piston), its temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperature using the kinetic theory, in particular noting wha3ljh 4dwu.vz.t happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force ondw+ +ausiw 6izb .wg7u 8cd66g an aluminum sphere submerged in water increase or decrease if b6+i76u.w+w gsz iuda 8c6wdgthe temperature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theory and8 *-kxmc)+(s1dwtyehptrh b; the relation between average kinetic ener* + p1d b;hh(mt8)xs-ckyrte wgy and the absolute temperature.

Explain in words how Gay-Lussac’s law follows from kinetic o2vg1w6-nvfh ax8 l5 ;i *qfaftheory.

As you go higher in the Earth’s atmospzf 6( ftfyhpye2j*+d2here, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth aim14 p via0-2c 7dpf4/qwovt 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 the Moon has practically no atmosphere.mdi i0 /v -f1ota74p4 2acvqpw

Alcohol evaporates more quickly than water at room temperature. What can youo8u- 1sx. d7, yuguea oiri7. )d1sge5jv)utu infer about the molecular properties us7is 7au),ry-1dtudg. 58oo)u giuv.1exje of one relative to the other?

Explain why a hot humid day is far more uncomfortable than a hot dry da.n)ht.uzev5d k; bsl:j+w 9wg y at the samebs.dwgn9h)t+ j5w;v: .e kzul temperature.

Is it possible to boil water at room temperat e0h0v s+bsyj2ure (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the sol/xb ub i sarwu1mlqe;+s;-s s +k1,/ame but the humidity is different. Which is more dense, the dry air or the humid air at the same T? Expsbr /+-1 le;bu1kxiu saw/s+;os,mq llain.

Explain why it is dangerous to open the radiator o,rn h;s:6vnucap of an overheated automobile hnr,uo6 ;n vs:engine.

Why does exhaled air appear as a little white cloud in t+ 5nybf gh/saau8) qn.ib5rhta3)tn2he winter (Fig. 13–28)?

  How many atoms are there in a 3.4-g-w fuavzk7u1 dy+;u-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring comp w (nq( e;q)t3hctqf; 8ixbuah1,d(n vare to the number in a silver ring of the ; 8x cq1n(d,b )e uiafh ;q3hwtqn(v(tsame mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68.t/d7vp wb ul2°F. What is this on the Celsius scale?dwu.2 plvb 7/t   $^{\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 temperatures recorded are 136 1z zpwi mighy s 9g8,a0cr-y5bi3d.;t b;8wed $^{\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 tf( ej 4exnv:d5hermometer, the alcohol column has length 11.82 cm at 0.0xe4 :f5jvd(en $^{\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 m 96z ;bp4 ,zny(evk jpzu/ -srvlong (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 wroug:tbora)n9 k3 w(u mqjf g9y n7p-+0cpoht iron approximately 300 m tall. Estimate how much its height changes between July (average temperature ofypqnk:- j (p o37nartgfbc99)o0mwu+ 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 l)lpy+r. 3lt flrx vt 44,.vl-y4rvabgarger than the rivet hole are often used and the rivet is cooled (usually in dry ice) before it is placed in the hole. A steel rivet 1.871 cm -)t.ty l44gvrbplf rv3.lvx y4lr ,a +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 zg,vxtl8:jly+ i4t, xgn8 /ml4 $^{\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 its change i1hmhb8v0 8 hsywgd;2 zn volume if it is heatedw8zgs28 hdvm;1bh0 yh from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is fil7gy+h-p+n2 ly7gylmoa ir0 k4 led to 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 55.50 mL )mf-j*+seo hki*k4 tjof 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 place*a g/3lhagf ot;d6p;ed in a ring made 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 exa2m x5uio5wvakrd2vd51 1;w lpand in essentially one direction only, show that the effective coefficient of linear expansion dwmiur2a5okav5 ;lx dv151 2 wis approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the chkql5z y2w2qg c9zm.5bange in 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 leb.)s,jwnc - shngth l and width w has coefficient of linear expansc w)b,sjn- hs.ion $\alpha$ 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 isoq 7g-f-x-ioc ptropic 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 brass and keeps perfect ti:vh7r8n7fc0mg r 1iakm17tu sme at 17rmv k8ufgh trs7:1ca01n7i 7m $^{\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 72jdjzh yvid6 +5la 7o0.140 mm. The bulb has ajd67+ 2jyl zao7dvi5h 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 rotatingnp) ka*egmt (ybd8x14 about its *(e) 8p tkby4dg nmx1aaxle 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 the desired length when at 15°C. How much sy(:a(fns jq .cfjs*;atress is required to keep as: q.(j* njy( s;acffit at this length if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-bea io2psi b/,gyp a 6,ia3qjy9a1m 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.r(mg41)p tu .i :ipyxg122 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 teqo l1uaj; ajafhtwi) 6n :8*yi( kd.(vmperatures 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 teylime.b3,b s.:bcov /vh 5 )yrmperature on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun a64+lmg t vtj kp-1m*hcre 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 engin*0hn6v f mry ws 1sncu9m-5zz;e, air at atmospheric pressure and a temperature of r91w0h*s6 -; z nnmfvc u5zsymabout 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 using txdx9+.s4 3) do qz2q jyluzx4bhe ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of nitrog.q6uxax9t 6j fen ($N_2$) 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 1jw 56g58+louklgal bof 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 iyqftwiri a-6* 3tz+cb1x.y u9 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 argoshd3 hh;/*plln gas at 3h/;l dh*hls p385 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 1bjv h-6x4y pikg 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 ing.ja6anf :i i(side the balloon, which makes it less dense than the air outside. Suppose then.f ja: gia6i( 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 at 15 d xp(/4w6jfzj tpi,w0z b.1aa$^{\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 0k.wzpcj4t6sx l1:kx.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 escapes a child’s hand at se0w,khhpjn2w,k* q cr 7fl9* 8bpd,8lntsua g4a 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 / (j(s6ylflt 0s 7qjoe2$m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000;w899lk t5ws4 yrmg bv L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) moles,7q2y/*fcg0l2 6ptdh yd ui8i2 q.re z9ks:kfe    $ \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 5i xjo 2 qy9o*,gunb2)ii*1kix.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 thatyw z* onk-g+t) were also in the last breath gztwyo k+*) -nGalileo took. [Hint: Assume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kf- lgb/ wuvh-7inetic energy of an oxygen molecule at STP? w/-fh7 bl-gv u   $ \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 surface of the Sun at a t dv3j2mupi .x6emperai3u62 j.d mpvxture of about 6000 K.    m/s

  By what factor will the rms speed of gasikb 5 st;4 akc5;6vyiksz 4)ci molecules increase if the temperature is increased from 0 4aiibk4)c i z 5ts;v5k6;ksyc $^{\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 al-4a:u)uv ra, given in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3,au:ava l )ru-4 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at 20.04pz:elr. lvf6 a( (fce $^{\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, by wh2vqp q(/njsj5z 2ps+jat factor 22 n+/qjj q5vpp s(jzsdoes $v_{rms}$ change?   

Show that the rms speed of molecugwpgmpzc z q :u,9((g3les 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 wljv o*ufa9+ lusokg j05 9k))two gases at the same temperature, the ratio of their rms speeds is equal to the inverse ratio of the squarew g 5a)u9so0vko9llk +j* j)fu roots of their molecular masses.

  What is the rms speed of nitro7ka2 -nv07h9aab c.td-rhat 4iedn +dgen molecules 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 speed of an oxygen molec-fh 2laeswiz6tg)zz+,, mxjfc 0l)w/ule 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 betwe8-ce;c) k f1py7p3qfcqr )36 nimc3 xiq/qlhfen nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whoseiceeyx)* 2js4et* hq5 molecular mass is 89 u in a living ce q4heces e2i)yjx* t5*ll 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 of3+a iglct8kqfa)t 8rk.wm ::h a 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 xs : effztvt7 *)2gx- *mgty:quranium, $^{235}$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 phan c-pi.l6tb5 jses 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 qf2hpkw 36j 5t9rxp6gd the temperature is (a) 90 5jgf3 92w6rhpqx 6tp k$^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximatel,9rm+g5* hj /; uhexctsdi zh:y) if the humidity is 50% on a day when the tempe;+rs xj d m,ih:9hue/5ctz*ghrature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water boil3 n+ogsthy mb-x44dz 7s at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is 0.72 atm.u-b7u3s3qc.j xej1ge+c kxz , estimate the temperature at whichx. c3xj7 3eu+. qjeczgksb1u- water boils. $\approx$ =    $^{\circ} $ C

  What is the temperatur o;nwws:o 4q77aa+ rwse on a day when the partial pressure of water is 530 Pa and the relative ha;o7w7n o+4aw:r ss wqumidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the temperature yd/)3uj)rtx8hk5)n4eutdn 6p;ngnr is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressurepl9s +c/ay.d* kum :fy inside a pressure cooker if the water is boiling at a temperature +ymfs kld*uayc.:/ p9 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 o a90 nte1zz3hjf 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 point of jfe c*cwu p9vp812 pp)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) to difgaxpi.4 ;5 2ejd.wlvd. :hxn mfuse a distance om5njd api. ;v dx gwhex.2.:l4f 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 ted md+)h x8uun5p)p;vhrough tiny tubes called tracheae. udn;)up pm +e5 x8v)hdAn 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 has been cali*z, bq8q7qoywbrated 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 5iq;glu*un- hh92 x()m dy vfdhas 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 Pyrex measuring cup was calibrated at normal room temperature. How much er*kz 2 xk1z d)iq;/pwsps:vl0y hrvb6;ror will be rv)d 6zpq/zlikw0pb; svsh :;k x1* 2ymade 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 w*zl4ki y. fzm8g 2fg:o3bx,k+wne7b a helium gas cylinder is initially 28 atm. After many balloons have been blown up, the gauge pressure ha8* enyl g3w o .mbz:4fi ,kwz7gx2bk+fs decreased to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air molecules in a room of la+ct5cpk 6:sn kdjf )4ength 6.5 m, width 3.1 m, and height 2.5 m. Assume the temperature is :s+pnc5kaf6c kdt j4) 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the denen-ev51qwkg ik,s1n3 sity 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 ab (f c*us;qq+gttainable using the best available vacuum techniques is abou(*bqfqc; gsu+ t $10^{-12} N/m^2$ 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 capacity of 5.5gogqre6er-l+to; v: 6 L when 10 m below the surfacevl-gr;:orq+ e 6goet6, to what volume would his lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmosph 9xt)s2uhcx0 nere 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, t20hxx snc9tu )he 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 increa.d.nec l5frh;sed 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 770mvq52rrcg4yly2) ghb)$^2$ (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 pressurz nk lyi810y sy,yq6l3e at the surface of the Earth, estimate the ylkl y0 63 8y,syn1ziqtotal number of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contained 6nkce ,:fqyi;c54q)o bl) 2leau/lpsin 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 h n)+n.t, dzogused in a hospital has gauge pressure = 2000 psi (13,800 kPa) and at T = n og+),znt.dh259K 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 liquid merc9tfi6h9-r nt:quq.o 5s ofs.aury 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 at r 4kker,(nq*y+s4pa m;q6(0xttxhr l0$^{\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’sx0u ,m+g7 sc pj95gcgh equator 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 mw1 3796q,i lc qekcv vr9ypx)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 sta 8xsqk(vgjt3 gpdee,;* cg 58ondard, 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 a pressure ofmknz1k1+am0:t)na bb 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 fro7vxo1uuslq.g q l3/o rt g2l+0m the 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 li)9kiw zvu8p9t- lfcm+mv /3ezd is suspended 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 fz)3mp - ve9wmv8ci z/t+l9ku and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter (spherical) bubble of air from(uenr*dsk ui3;m.lx 6+ tcx1 e 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 md ktluees;(*r.u +3cnx6 xi1when it reaches the surface?    cm

  Calculate the total watt7ou;)zhl 33l(jow3 5wrhlkv(e /k vler vapor pressure in the air on the following two days: z3(3ookhelvrwl 5klv )w ;(u37 tj l/h
(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 STx+wx dl d;+.wtP, and when it is a solid wxt w.x ;++dlddeep in the 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 an idea1+ mmiseos6 0fd 2yy8(dmhwpkd s,4b5l gas at constant pressure, the coefficient of volume expansion is s edp2+m f45hs d 18(oyd,si6kymbw0m 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 thei-e0ynt3vn 5vtr cellars to prevent rot and mildew. If the cellar in a houne3v t5ynvt0 -se (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