Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodic 9gn.dhoz3 rc o8qt6 p:hjh+ *btable or Append3q:z8d th rghjpoo*ch. b6n9+ix B.

Name several properties of materials that could be exploited to make a tgva 627rp7 hcgl n fwrd.h.g8.hermometeg7f7.6ndra8w2 grh .h v.plgcr.

Which is larger, 1 C 4.a 7pgn egn 6ac4dh(o$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with sye1w8 jcj 39b-;gkm mjrstem B, but B is not in thermal equilibrium with system C, what can you say about the temperatures of A, B, and wk193-jm; bmg8cjrje C?

A flat bimetallic strip cf c+ om+)ial8n.qawn8onsists of aluminum riveted to a strip of iron. When heated, the strip will bend. Which metal will be on the outside of the curve? [Hint: See Table 13–1.] 8mn ca q+i8.flnow)+a 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 x/r k0hp k:gq.zcdfrwl7 ap9813/xsjlinear 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 furnacomzqfl52vwb 2l,11 vee (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 can flow to touch both contact wires. Explain how this device controls the furnace and how it can eml1o52qvlf v2,zb 1wbe set at different temperatures.

Long steam pipes that are fixed at the ends often x0e i++h1 fwelhave a section in the shape of a i efh++ 01elwxU. Why?

A flat, uniform cylinder of lead floats i*;c eu0s3aachb vs (5b).pb uidari6. n mercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometzugy0asufoc:ryw tb 0fj 77i4,pf 4* 7er is first placed in a hot tub of water, the7z yfb07at ,crisfu: j4wog *p74 ufy0 mercury initially descends a bit and then rises. Explain.

A glass container may break if one part of it is mz.r-*xa l-3enfn -pxheated or cooled more rapidly th.-x3--rnex* p flanzm an adjacent parts. Explain.

The principal virtue of Pyrex glass is that its coefficient ofh.ovlts6n 1h/ z0uj)m linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyr6oh /.0j z h)ntml1suvex.

Will a grandfather clock, accurate 22ttjgn +c7rgat 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 tooq+ 2omah7c+x bulge so badly the can will not stand up. What has happenh+ c2aqm 7x+ooed?

When a gas is rapidly z1sr6 el *yiw9mux v18compressed (say, by pushing down a piston), its temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperature usinsxvy*8wu1z i1 6er9lmg the kinetic theory, in particular noting what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force on an aluminum sphere submerged in waty/x /v39 ylfkcer increase or decrease if the temperature 9v/k3x/y clfyis increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s.4e2gr;vs 9wfd(pi3u3ubes yvs b 3t: law follows from kinetic theory and the relation between average kinetic energy and the absolute tempera3sdv g :93s.suvt (w3 biperfyb2u e4;ture.

Explain in words how Gay-Lussac’s law follows from kn64mn(7g pxdy inetic theory.

As you go higher in the Earth’s atmos7g;kof 2fi83axhq8rs phere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth rw, 6)m7znrh) gyzv*rpj 3lz cv -o5l*iefers to the minimum speed an object must have to leave the Earth and never return. The escapelo n*p c-3l6h v)ryj*z)r5 i7gv, zmwz 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 rb etd-:t sg9+room temperature. What can you infer about the mob-d :gr ts+et9lecular properties of one relative to the other?

Explain why a hot humid day is far morov r 5sd3 u76uq;nrb(ae uncomfortable than a hot dry day at the same t; r 5av6b 3su7drnoqu(emperature.

Is it possible to boil water g o2+z olkc*b+e 7 zkmjeh158fat room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is 1z+m*5xyo)z m wh(e xhthe same but the humidity is different. Which is more dhyz+xm 51 )w*oze(mxhense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerous 5zx 9k ztoxzqj7-f:n8;;c6ne:exlx nto open the radiator cap of an overheated automobile eng-;z:z:9j cfxx56e8 nezx 7o;knq tnxline.

Why does exhaled air appear as a little white cloud in the winter (Fig. 13–28)?1e+lgvgcn 7y dl a *ri/0mzrwlk+,o- /

  How many atoms are there in a 3.4-gram coap3 b ,t7ucbb1e (hi:ipper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring co +bvk f/c6gc)k6o:8p ) z;ycpgctf 1qhmpare to the number in a z) t+):pf o8b1kf6;6/vycggc p cqhcksilver ring of the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this on the Celu j n3xte4l81vsius scale?3 vnu1tlx48e j   $^{\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 tempvaf7bnim 7 v28eratures 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 alc *ewk2xpytli 0rk8atvm ) 554rohol column has length 11.82 cm at 0.05 8tw t5 vkirm*pyrea)lk2x40 $^{\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 bueh 7uh 7mvr l.+sq6:jj+l-eorilt 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/mng c19lky. z built of wrought iron approximately 300 m tall. Estimate how much its height changes between Jm9 .n1lyzgc/ kuly (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 tdfw)ajgr6mizb: c7at3k1;* ohat are larger 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 i 3 zja6w; iog*7kaf1:rc)m dbtn 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 f7msakq) )p)*rq2tfj1(jvwue 0b 7gg4 $^{\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 itnf8h l:dz (:mes change in volume if it is :f8:hml ( znedheated from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled )38ceh6m*)rk uudrzfto 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 on hs(elj/9v ,cf 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 bi:g gf4htji5 0wl 6w3ue placed 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 expakco6/m ds,xdf )ter.9 nd in essentially one direction only, show that the effectdds r/f t,m)cke. 6o9xive coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the chanaz2l/ + kequ3yge 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 length l and width w has coefficient of linear e5*xw +) unnaodxpansiox5dn*own u) a+n $\alpha$ 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 pt,o vuf; :9jtsolid, $\beta$ = 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 grand* rut(mgt 0.lrfather clock is made of brass and keeps perfect time at 1( rur*.ltt mg07 $^{\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 ao-afef c- tdxw )pr1(0n inside diameter of 0.140 mm. The bulpx -ff)0 ca(to1r -wedb has a volume of 0.255 $cm^3$ How far will the thread of mercury move when the temperature changes from 11.5 $^{\circ} $ C to 33.0 $^{\circ} $ C? Take into account expansion of the Pyrex glass.    cm(b) Determine a formula for the length of the mercury column in terms of relevant variables. Ignore tube volume compared to bulb volume.

  A 23.4-kg solid aluminum cylindrical wheel of radius 0.41 m is rotati8c f,8odquo+jng about its axle d,+8fco8ujo qon 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 stress isx+ 9pjb0 subf; af908 wqr(ok3vtx yxqz*7t .a required to keep it at this length if the temperature incr0z( ypr ja+a qf3uk9s78bx0.bx wft;xt*9q vo eases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-sectional area 0.04i3 f4y ycc0bs)1$m^2$ 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 c kfds+3*jc +irm 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 th:ukm8( r) ml*c bt(ka u4i3.rvtj6vcze 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 temperatu+t llk 0z az0rr c7r3f6;pyuh)p;dv6-;essmfre on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of th;nz-kkbejscd ykp1t-v,an ;0b f3- 2;h uhj:te Earth and Sun are about 4000$^{\circ} $ C and $ \times10^{6 }$ $^{\circ} $ C respectively.
(a) What are these temperatures in kelvins?    K    $ \times10^{ 6}$K
(b) What percent error is made in each case if a person forgets to change $^{\circ} $ C to K? $\approx$    %(Round to the nearest integer) $\approx$    %(Round to three decimal places)

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

  In an internal combustion engine, air at atmospheric pressurere,3xcz:(cp 2h lxr0 x:hku9u and a temperature of abouu90 ,x xzpkchu2rrl:e( ch:x3 t 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-tu *7vu p:odx at STP using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of /6 to*a0tna tjj qct wa,cb0(4y. ;shrnitrogen ($N_2$) 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 contaifp6q8dtrh.bc p,g /5v ns 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 14eejn ) b6 qvie+urx/is 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 105d l4pu1rj-5b2 +hgd:tzg,gr hk5t 7kk.0 kg of argon gas at 385 Ku5 dk ,7g kj bl1zg4phh+t:-r 5k2rgtd?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg of pw;sf* 3-u yfp$O_2$ 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 tx 3,2hlj4 jkothe balloon, which makesljo3j 2thk4,x it less dense than the air outside. Suppose the volume of a balloon is 1800 $m^3$ and the required lift is 2700 N (rough estimate of the weight of the equipment and passenger). Calculate the temperature of the air inside the balloon which will produce the required lift. Assume that the outside air temperature is 0 $^{\circ} $ C and that air is an ideal gas under these conditions. What factors limit the maximum altitude attainable by this method for a given load? (Neglect variables like wind.) $\approx$    $^{\circ} $ C(Round to the nearest integer)

  A tire is filled with air at yh( ja 4l2dy -e/lyu-d,us ;jrmf v2(y15 $^{\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 18.0 jm/b18 jk )i+k1w8u(my(xq zzxqdf.b$^{\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 sea level nq s7k lt kt l)k+9 /wm0kwu(e62fhum.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 hn.x7, fkus9s molecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? Howtb+nvjytn,kf(q3 , 9a many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) moles, u-i4 . li6i ;x*pnml9k(acra c   $ \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 e82*mfn7bej h 5.1$ \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 a6qzo(lg1mp w ats5 l9nt 6-(mqir are in each 2.0-L breath you inhale that were also in the last breampt( (16tzmqso l6 5ql9ag-wnth 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 ox2mdtv7hvsd nf e3h )))ygen molecule at ST7)2tdsd)ehfnh ) vvm3 P?    $ \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 0bwb7v ed7q3 eof the Sun at a temperature of about 60073b v7bdewq e00 K.    m/s

  By what factor will the rms speed of gas moleculeayuf0o +yhow x)yy88c g7n6.v;v)vrz s increase if the temperature is increasedcy)honvo;y w+ r gv 8 8u6.)xyaf7yvz0 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 s*ww; gey/b7yx bk)e v.2(pjgfollowing speeds, given in units of km/s: 6, 2, 4, 6, 0, 4, 1,yxgb(.ev yb ws;/e7 )gw*pjk2 8, 5, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gasv4a8ls6k x .v9qz3ws zqiy+9b 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, by : 6y;ccqi3mdr what factor does ;cr m:yd6c q3i$v_{rms}$ change?   

Show that the rms speed of molecules in a gas is givfm1 ,ucoh v9uw jg;65ien by $v_{rms}$ = $\sqrt{3P\\rho}$ where P is the pressure in the gas, and $\rho$ is the gas density.

Show that for a mixturgcqq )0y-7,biyo/yqf 2y vz 1ne of two gases at the same temperature, the ratio of their rms speeds is equal to the inverse ratio of the b )yqq o7/zyqigyn2v,y-c0 f1square roots of their molecular masses.

  What is the rms speed of nitroge3gr zeope8:* i69 aep:rt7plj n 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 a ai5dsd* m0lv/n 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 distij(;l.nq2vn cz x(t2o(idv0s ance between nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular mass is 89qqf2lpuq0ch h95r.08c2 fxcm u in a livingc2lmfh.cu2h0f p0q5 89xr q qc cell at 37 $^{\circ} $ C.    m/s
(b) What would be the rms speed of a protein of molecular mass 50,000 u at 37 $^{\circ} $ C?    m/s

Show that the pressure P of a gas cggd4to+6x ,5 fiuo3t yan 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 uraniumnua1:v) a4cse , $^{235}$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 pheepuyl 2h+z;/u mqs29d* r 2xqases can $CO_2$ exist? (b) For what range of pressures and temperatures can $CO_2$ be a liquid? Refer to Fig. 13–21.

Water is in which phase when the pressure is 0.01 atm and the j 3bh5 add b1*cgaj0m;temperature is (a) 90majbc1 gad;*h 5d0jb3 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humiditoy;b(*w 4g51lsh pytay is 50% on a day when the temperatpbwy(14asl; hg5 *yo ture is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water boils at i i 26bp+*+j8b4gr d1 s*wx av,ikitym90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is 0.72 ije5kic 7 ez s;qsp:*uzx ./f/atm, estimate the temperature 5ifjspeczu:ek . z i7 /;x*q/sat which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure u rm-wi6d4- m *-vctvwv*bgx9 of water is 530 Pa and -g-d*cm wt4x ui vrv -mb69*vwthe relative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressyoial-::e rxfqk ; nke+35 /osure 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 pressure cooker if the water is zg0,rt;bxseb c 829ng14 oyo aboiling aaen84 btsocb;g0 2 r ox9zy1g,t a temperature 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 of volu,2 ytuzt(yb3j 4/)j+ dqqtjs eme 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 pom )qourv els8p8oz* ,k 48wvh8int 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 (seeko /-th(aosd7 xg--(vuw5fkb 0 xvn)p Table 13–4) to diffuse a distance of 15vx ud-t-x) ksgpwhf05(o a- (/bn7vok $\mu m$ 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 jsork,lm; y, kc +49oysurface of insects to the interior through tiny tubes called tracheae. An average trachea is about 2 mm long and has cross9 y 4kcj ;lomor+,,yks-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 ber ,3us1 r-rqkmot ss4s6y k/v5en 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 bel7 90vj 5wtpyyen 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 ekz j7wy jgla/+dw0v-1d o+;xc3paq ) crror will be made in a recipe calling for 300 mL of cool water, if the wateczd+ -w+ yda3 c)7j/gkopa;01 xljwvqr 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. After mpyavjr :o5.8g any balloons have been blownpj.ro5y8: g av up, the gauge pressure has decreased to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air molecules in a imqcjqt 0x-3 k*d00 wyroom of length 6.5 m, width 3.1 m, and heighj 03-mdtk0 i qxwq*c0yt 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 a2gx5qdmljq7e68 pz 2*ock o;u bout one atom per $cm^3$ mainly hydrogen atoms, and the temperature is about 2.7 K. Calculate the rms speed of these hydrogen atoms, and the pressure (in atmospheres).$v_{rms}$ =    m/s    $ \times10^{-22 }$ atm

  The lowest pressure attainable using the best available vacuum techniy8c vtw+ayc58ques is aboccw85 yy8 v+taut $10^{-12} N/m^2$ 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 yhoerm)g 2h 8*3gemo2 lungs to full capacity of 5.5 L when 10 m below the surface,rg2 y e3ohm)g8*hoem 2 to what volume would his lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Mod77, w qrw)pgr: py5pav tee52on enters Earth’s atmosphere at a speed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of thqp7rpd)5 v,ygapw2:wee7 5rte vehicle with this speed correspond to what temperature? (Because of this high temperature, the nose of a space vehicle must be made of special materials; indeed, part of it does vaporize, and this is seen as a bright blaze upon reentry.)    K

  The temperature of an ideal gas is increased from f jukf3( uj+.y j0;tsz110$^{\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 77:j8t0 en ixaqh3 ruul5ubh se-1r33u-0m$^2$ (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 surface of the Earth, est)n+r78w g ybp53/(nv4fdpte 5 qjusnq imate the total number of air molecules invqnqfy+4w/ rd5gb 85njs p3 )7tp( eun the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules co r oc*yswupde+y0r*wb bmo/b3/ p2w2,ntained in a 7.6$-m^3$ volume at 4.2 atm if the total amount of nitrogen is 1800 mol?    m/s

  A standard cylinder of oxygen used in a hospital has gauge pressure = 2000 8 bcdr-x ,;hcwrs sb34psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure, is cs 3-r x8 cbc4,rdbws;honstant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liquid mercury a(fq21kxarml. s; lc5rpx05f q t 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 0-vj pqx 7s bw(h;l+pq( q,)xuw$^{\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 eq7y42d;vi a2e- hfn 7*9wbhgnco/uzf guator 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 g8 k z5-hf33lpt* jkzohlass 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, adopted i* vo*n +0 xuoxhx+kp)/3c/emm xkd/lsn the 18$^{th}$ century, was a platinum bar with two very fine marks separated by what was defined to be exactly 1 m. If this standard bar was to be accurate to within $\pm1.0 \mu m$ how carefully would the trustees have needed to control the temperature? The coefficient of linear expansion for platinum is $ 9\times10^{ -6}C/^{-1}$. $\pm$ =    C$^{\circ} $

  A scuba tank, when fully charged, has a pressure of 195 atm at7 x8ws*xno:/5biz r5ya ge/fr 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 Ear 8v *1z4kt,9b ao *fluhs01plt-6ipfe.cu iyoth is $ 1.12\times10^{4 } m/s$ so a gas molecule travelling away from Earth near the outer boundary of the Earth’s atmosphere would, at this speed, be able to escape from the Earth’s gravitational field. At what temperature is the average speed of
(a) oxygen molecules,    $ \times10^{5 }$K
(b) helium atoms equal to $ 1.12\times10^{4 } m/s$    $ \times10^{4}$K
(c) Can you see why our atmosphere contains oxygen but not helium?

  A 1.0-kg trash-can lid is suspended against grayv,na cgws 95eo+ 35.nn krph /*u)yuva su+*dvity by tennis balls thrown vertically upward at it. How many tennis balls per s3 a+,*o gu+y9dhu) v*acnrksp5s /.ywvnnu5eecond must rebound from the lid elastically, assuming they have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter (spherical) bucpios 6*n19dz2 a+tnkb)tzx o(x+v,cbble of air from a depth of 14.0 m in a lake. Assume thb+z izcx *k1sco2otv6t nnp(ad )x ,+9e temperature is constant at 298 K, and the 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 airxkge 9 2(/ zp1ktj.xui on the following two days: ezx (2. 1tg/j xpuikk9
(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 ;,s n:act m8puis a solid deep in the Earth where the mn:sc,pt8 ua;temperature is 2000$^{\circ} $C and under 5000 atm of pressure. Assume the bulk modulus (90$\times 10^9N/m^2$) and the coefficient of volume expansion do not vary with temperature and are the same as at STP.    %  ----待选择----decreaseincrease 

(a) Use the ideal gas law to show that, for an ideal gas at cons.(8 cf vltlqk3jga u05tant pressure, the coefficient of volume expansion is equal tqg5 c0 kjlv.lt3 8f(auo $\beta$ = 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 thev4m7q15kzg(ln *dkgk ir cellars to prevent rot and mildew. If the71*k5zm(q 4lg kkdnvg cellar in a house (kept at 20$^{\circ} $C) has 95 $m^2$ of floor space and a ceiling height of 2.8 m, what is the mass of water that must be removed from it to drop the humidity from 95% to a more reasonable 30%?    kg