Which has more atoms: 1 kg of irontys 2n 5o cso/(kn2xa, or 1 kg of aluminum? See the periodic table or Appendix ssn tax2,o5o kcny/ 2(B.

Name several properties of zmo7l/ s 43kfk4rwap/otc k,slc/j9 9materials that could be exploited to make a thermomet w9/loal rmsstjcck47f9/ /p43k o z,ker.

Which is larger, 1 C / i) , iz-bzjwc4*fwx ,vqi3uw$^{\circ} $ or 1 F $^{\circ} $?

If system A is in therm4le:,qh kmta28mm 5 f)k no7afal equilibrium with system B, but B is not in thermal equilibrium with system C, what can you say about the temperatures of A, B, andaf5m :a4)t7ef2kohm q,kn8 lm C?

A flat bimetallic strip consists of aluminum riveted to a strip of iron. When hcr7k tw3 yzah(3lbnzv2w5 vl +xme22 3eated, the strip will bend. Which metal will be okz253nwyv we m2c 3x3lzr+lvbt7(ha 2 n the outside of the curve? [Hint: See Table 13–1.] Why?

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

The units for the coefficient of linel f l9mgdi,qi5.pulv+zsz .*8s0 i1bkar 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 usenoggw:e0 3:7nhxm 2 jmd to control a furnace (or other heating or cooling system). The bimetallic strip consists of two 2nn m:hwj703 ggoxm: estrips of different metals bonded together. The electric switch is a glass vessel containing liquid mercury that conducts electricity when it can flow to touch both contact wires. Explain how this device controls the furnace and how it can be set at different temperatures.

Long steam pipes that are fixed at the ends often have a section in the shap 68wh.oh2i eeme of a U. he62hmwe8i. o Why?

A flat, uniform cylinder of lead 2 elo)aeu m8pw/vfx7qf:kf.v f3 /r 0sfloats 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 hot tub of wateqy qr.)ng+jnt x5o0.ur, theq.0tgn.5n) xjuyqr + o mercury initially descends a bit and then rises. Explain.

A glass container may break if one part of ig1 s6jklybuna ) .kg+x;n; vm3t is heated or cooled more rapidly than adglm3j+;;1 b.ykgs6 vk ux) nnajacent parts. Explain.

The principal virtue of Pyrex glass r uj zo n*;g4x00pisj1p u;q;his that its coefficient of linear expansion is much smaller than that for ordinarz*;00p 1uqx;4jsji ugorh;n py glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clo9l jz6iqo)hy ogrx)*(ck, accurate at 20 $^{\circ} $ C, run fast or slow on a hot day (30 $^{\circ} $ C)? Explain. The clock uses a pendulum supported on a long, thin brass rod.

Freezing a can of soda will cause its bottt3o(v 1s 0zmyc+t:v:k9t roufom and top to bulge so badly the can will 1t+r9(oukv y::cv t0z3tmsf onot stand up. What has happened?

When a gas is rapidly compressed (say, by pushing down a piston), vm*yfv ,c0aexf/b-y-t7h: rjits temperature increases. When a gas expands against a piston, it co0 vm*x ftjb,fv-: yh/ -7rcyeaols. Explain these changes in temperature using the kinetic theory, in particular noting what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force on an aluminum sphere submerged in water wye1f) (d jymv zw7a)(increase or decrease if t1m)(f v)zywa 7ydj(wehe temperature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theory and the relation (467b s a0lc6x hu* ahavug6sabetween average kiag *66 7ab6usl (aca4sh 0hxuvnetic energy and the absolute temperature.

Explain in words how Gay-Lussac’s law follows fr hf3zpei :+)liom kinetic theory.

As you go higher in the Earth’s atmosphere, thjvk-l ik9e46qy thgueh:33q h3rq0 , ee ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refer/ xlxj88js.dvs 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.x xdj8l 8j/vs to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at room tempe9d85 y(st lcy3;*h/ uocx*hsj 7fz tsarature. What can you infer about the molecular properties of one asf*8(3xh tc 7z/ csthy5 lysu9*jo;drelative to the other?

Explain why a hot humid day is far more uncomfortable than a hot dry day jsrym jy-o -b+v-g4td wdu sz2 .1o.,eat the sey sszjd-2td4-1,r w .u -g+ooybm.j vame temperature.

Is it possible to boil water at room temperatuici8t+nxrdv 4 q:n9i 7re (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the of5c4rg- a8d)d+rt9 lpq*zi chumidity is different. Which is more ) 9p c 8d5ir+rzla-gfq4od*ct dense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerous to open the g zzn4d3xu;3yc ox;ave- s67n radiator cap of an overheated automobile oy6-z;xe3dv7 s 3za;ncu 4x ngengine.

Why does exhaled air z:a9 ky nkwb;vdxf2sp9)s/t)4si oc+ appear as a little white cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3ewhx3vhtq,a geiq9) . lj mu)2wz43,n.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of aq fts g.z0x2;ctoms in a 26.5-gram gold ring compare to the number in a silver rif; g 0c2z.tsqxng of the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is kue)t q88*o)n g(xr)9avgfl ck 0,qepoften taken to be 68°F. What is this on the Celsius scale?uvk)ler8c) np(tq,og*) fqa k80 e9gx   $^{\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 qhnig. 09 u3q,pdzo ;uy/rt msy-:1wu 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, t5dl/+f t-cr8jqir*;4cy rxeky .cu (che alcohol column has length 11.82 cm at 0.0.5fqr urjckl;4ey/xci yc t8r(dc-+* $^{\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 - 8or+pzp8 p jvqf0zi4a,uj, gslabs 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. z+rr3 r baeme;f- 6lkfe9xb1-13–29) is built of wrought iron approximately 300 m tall. Estimate howrbe6k 9m; 3e1rl-e bx-rffa+ z much its height changes between July (average temperature of 25°C) and January (average temperature of 2 $^{\circ} $ C). Ignore the angles of the iron beams, and treat the tower as a vertical beam.    m

  To make a secure fit, 5ne zxnfxn)7n(w06d a rivets that 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 1.871wa z7()xnend0xn 6 f5n cm in diameter is to be placed in a hole 1.869 cm in diameter at 20 $^{\circ} $ C. To what temperature must the rivet be cooled if it is to fit in the hole?    $^{\circ} $ C

  The density of water at szz8/l4 h3mk :/onfou9 mj+u1y ,bmhsi7y bj44 $^{\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 in x:z+ t)-tv koq60gnats change in volume if it tx z-g6nv):nt0oq +kais heated from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350.0 grmno-pz5 i-tebgw )(mj + 504jq,tj jmL 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 m4nnav8ad ef8-*uyqw 0L 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 placed57qbdxu;vw 1t 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 expand in vq:(z p3c qk3a c-25rrj3yqjy cv,f7dessentially one direction only, show that the effective coefficient of linear expansion r5zq:yjqrv3 c pq dc-v3f ,c2y(k 3aj7is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the denscem xa9w 7,mag,iwcn:. vu3-tity $\rho$ 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 akrilh85mc 7 6and width w has coefficient of linear expansion kla57 68ch rmi$\alpha$ Show that, if we neglect very small quantities, the change in area of the plate due to a temperature change $\Delta$T is $\Delta$A = 2$\alpha l w$$\Delta$T See Fig. 13–30.

Show that for an isotropic solid,zw14bhnp e,egjfluy)5 b)2. j $\beta$ = 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 u g0prvf3p 5md(8i.nkperfect time at 17805vgd fi. muk3p pr(n $^{\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 0.140 mgrnujwd;bd-ru22 xm ui:-,(p m. The bulb has a volume o2rurj--(u,iwundp2d ; x:m bgf 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 w. k; wb(s)/zw,tcv hgis rotating about its axle on fricti,gk;w.cw /bvw(zh )stonless 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 is re *ccbzssoke(* hk1u8ml p0) 7jquired to keep it at this length if the temperature i( *oj*uc7kzcphke)08 b1slsm ncreases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-sectional area 0 ) xezr,(flc:a1vt1du.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 134.12 11-ilyehu-nsmr u6* p2 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 temperatures on the Kelvinlr( v 1p1bqp cc6;hzmjn2 +mv: 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 ttb6z95 .*h io tuhob3che Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earkv-al*82 lo0w(j:ylt8oihpz th 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 combusq ,0t4kmogynma7; wk)tion engine, air at atmospheric pressure and a temperature of abogt ;q,no 4k)wm7aym0 kut 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 the ideal gavtivu lw sk2py51)a)6 s law.    kg/$m^3$

  A storage tank contains l)*u2ova4/k jokv;* .z gk ray21.6 kg of nitrogen ($N_2$) at an absolute pressure of 3.65 atm. What will the pressure be if the nitrogen is replaced by an equal mass of $CO_2$    atm

  A storage tank at STP contai9y.xti7ge h) dkc:* sins 18.5 kg of nitrogen ($N_2$)
(a) What is the volume of the tank? $\approx$   $m^3$(“Round to one decimal places)
(b) What is the pressure if an additional 15.0 kg of nitrogen is added without changing the temperature?    $ \times10^{5 }$Pa    atm

  If 18.75 mol of helium gas is ato8s:gatvimvd- 85 5gi 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 10,yyp u6a;lz o)g 3)0dz:t mlld5.0 kg of argon gas at 385 Kl yyuo6 )pt la:l,;gd)zmd30 z?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg of 7g cfl andlran7-2(j4 $O_2$ 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 tuqmr g+v77v g jp:r:(inside the balloon, which makes it less dense than the air outside. Suppose the volume of 7:ruv7pmqgj+ (r tg:va 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 witzm6m(kd33jhy 0l) ptd h 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 abio//bd1c w (c o5*pmelmu1nqx.p0s-t 18.0 $^{\circ} $ C and an absolute pressure of 2.45 atm are compressed to 48.8 L and at the same time the temperature is raised to 50.0°C, what will the new pressure be?    atm

  A helium-filled balloon escapes a childb8xme8z.vj u kw1d ;d/’s hand at sea level and 20.0 $^{\circ} $ C. When it reaches an altitude of 3000 m, where the temperature is 5.0 $^{\circ} $ C and the pressure is only 0.70 atm, how will its volume compare to that at sea level?    times the original volume

  Calculate the number of molect i/ekj-f3xg x()h ip(ules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How many3cpx x06adh cl:db;d / molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (2g 6 jr /xssy3dpng3p-a) moles,    $ \times10^{22 }$ moles and (b) molecules of water in all the Earth’s oceans. Assume water covers 75% of the Earth to an average depth of 3 km. $\approx$    $ \times10^{46 }$ molecules

  A cubic box of volume 5.1 -j88zjuz kou4$ \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. y.nq vo0 -g:s-o3kqla0-L breath you inhale that were also in the last bre3l:asq vo -g-.no0qkyath Galileo took. [Hint: Assume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average xenkf, o:g1grv q2d f-/xgjxgz 39 r3)translational kinetic energy of an oxygen molecule at STPxedgx f2/3) knzg:ox q 9f3,g-jrr1vg?    $ \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 tj8 c(bik cfwx48 v;mz,he Sun at a temperature of about 6000 4ckb xvfzw jc(8i8;m, K.    m/s

  By what factor will the rms speed of gas njouwzhpk 3/) k6,*tzmolecules increase if the temperature is )tp*k j/o, h6z3wuzk nincreased 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, git , xs-wzoos3(5v vqj4ven in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calc o 5xowsq-j4vs tvz(3,ulate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at 20.0 m 4evs ;9s+k2z1ra2gqgt.dja$^{\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 doublb 5 y fws7og56uvi4l3ned while its volume is held constant, by what factor 5y oisufln6g3v5 4w7bdoes $v_{rms}$ change?   

Show that the rms speed of molecules in a guwf* e:u7 m oytw7w:2wf5t8wlas is given by $v_{rms}$ = $\sqrt{3P\\rho}$ where P is the pressure in the gas, and $\rho$ is the gas density.

Show that for a mixture of two gases at the same temperature, the ratio 04u4kd x 3s;j:pbsi uxof their rms speeds is equal to the inverse ratio of the s:x 4p 4sj3bix;udkus0 quare roots of their molecular masses.

  What is the rms speed of nitrogen mola ca1/2pomk zhnu/q1n4/ q) ppia: 7lxecules 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 oxyg-o7m;n uyr ka /c3chhl89pw:e en 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 be2l5zjp/;p75skg tc r1n8spiq tween nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid/ r 7ep *f/j+xeuhlbh8 whose molecular mass is 89 u in a li7* eu/+ pe/rhxfblj 8hving 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 gasa6fg gst82m*)mmi nw (d7 qpt2 :;tfaq can be written P = $\frac(1)(3)\rho v^2$ where $\rho$ is the density of the gas and v is the rms speed of the molecules.

  The two isotopes of uranium h f1w0 gfgpzp9s 0b;sn+kl5r1, $^{235}$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 pressunf.dl1gqt- , cre, in what phases can $CO_2$ exist? (b) For what range of pressures and temperatures can $CO_2$ be a liquid? Refer to Fig. 13–21.

Water is in which phase when the pressure is 0.01 atm and the temp 08neug. x1yc5jzl f.vw6 1rxrerature is (a) 90 ry e5. w1 gz6 f1ln8.xcrjvux0$^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximateljrllds 34wf44xs1k g-y) if the humidity is 50% on a day when the temperas wfl 34gjxl s4rk-4d1ture is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place :e2t s1*dl;bt5ifk wlwhere water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place wgpnyj+g,,zru1lm 1-in the mountains is 0.72 atm, estimate the temperature at wg, r -zyj1 ,np+umw1lghich water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of water is 530 Pa iud ugu . +b zia41. jle;0mojnnl4p-0and the relative humidity is .uilum;dupn 010ljg4e-b4j +zaoi n.40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressurf;j0 he2tzcn- e 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 i*j.8q .wdsr-+t48qmiz tdnc pressure cooker if the water is boiling at a tem8 s-tr4jmzd* . di.itwqqcn+ 8perature 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 j1otl p;qh, i,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 m(8a5d .lrypfoint 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) to diffuse aocnnb7o 91x gx7-d(dq distance of 1oc7(1x9q7b ngo ndx-d 5 $\mu m$ 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 interior4fsu)mr6r)f)m-nyz at + gh- d through tiny tubes called tracheae. An average trachea is aboutafu- 6grm)fsyt-n)r4 +zmh d) 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 mo(9e;mj71:qzt 7ss 1qtwebp has been calibrated at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A precise steel tape measure h4q xegp(e )3k1elqh4u as 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 tzncmw cqj)s o. ,uu(5kyk.8l 4emperature. How much error will be made in o cz..uqj8my5(kclw , kn)4 usa 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. After m zo ib.;wa,2ewany balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of the original gas remains in the cyliz; e2, obwa.iwnder?   

  Estimate the number of air molecules7.d)+hkaquq j in a room of length 6.5 m, width 3.1 m, and height 2.5 m. Assume the temperature is q7ak ).ju+ hqd22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is about one p j ,lmh olttjuna/22l29 h8)oatom 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 9 ;wt,s 0lzid-x tqx/sbest available vacuum techniques is aboutd t9 l- ts0,xi/sw;zqx $10^{-12} N/m^2$ 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 capa97n:m565.yarx (hz jbc ecyjf city of 5.5 L when 10 m below the surface, to what volume would his lungs expand if he quickly rose to tj eybrjm x:c95zh a7ny5(f.c 6he surface? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmosphere 4y6mpaf4c*lyw1j8m k at a speed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this speed correspond ty8cfmkl14 ym4pjaw *6o 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 ideac0 gxc y);vuto(u ingp w).9-bl gas is increased from 110$^{\circ} $C to 360$^{\circ} $C while the volume and the number of moles stay constant. By what factor does the pressure change? By what factor does $v_{rms}$ change?$\frac{P_2}{P_1}$ =    $\frac{(v_{rms})_2}{(v_{rms})_1}$ =   

  A house has a volume oue, b ohn;k2tg7er.. hn.cr3 kf 770m$^2$ (a) What is the total mass of air inside the house at 20$^{\circ} $C?    kg
(b) If the temperature drops to -10$^{\circ} $C what mass of air enters or leaves the house?    kg

  From the known value of atmospheric pressure at the surface ofs67 cb5csa /rx the Earth, estima5 acss6/bxc r7te the total number of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contained in e qkjknec( n/65w--f4ccdt .aa 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 pressurecjke;;7ys /7i xvoe4ucs ,de. = 2000 psi (13,800 kPa) and at T = 259K How long will th;7 vcjk7, seedsy /ecx4iu;o.e 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 mercury at (cohry *.k5zuq6p; f j0$^{\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 ok a(l * a2ig*fsx91akat 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 fqrx0 f,mo07t)n wlk t4it snugly around the Earth’s 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: b54rk1 h 6god23tqkq 7zadfy a glass jar at 20$^{\circ} $C. To help open the jar, it can be placed into a bath of hot water. After this treatment, the temperatures of the lid and the jar are both 60$^{\circ} $C. The inside diameter of the lid is 8.0 cm at 20$^{\circ} $C. Find the size of the gap (difference in radius) that develops by this procedure.    cm

  The first length standaogp(rt -n, :ttgrhey9iv k. a -34jns+rd, 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 of 195 atmq a(j - qj4fjtq3h1h(ce2uw+h 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 urk u9 m.1z-izis $ 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 t-zljsnkj4g +9hrown vertically upward at it. Hog9+s 4jn-zklj w many tennis balls per second must rebound from the lid elastically, assuming they have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releasepswp+- 8wmd;5nk gp5o s a 3.00-cm-diameter (spherical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the air behaves as a perd wo8pnms5k -;5p +gwpfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure in the air on the following two das,ly e3zrd i:7ys: :yzi l3dse r,7
(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, andvzja+6 /w)p rda8+q,m.hgvwk when it is a solid deep in the Earth wk/h mg8 zjw6p r.wa, +)vd+avqhere 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 sho.c7z,n g -*/dbu*xhzx z*rhgdw that, for an ideal gas at constant pressure, the coeff x.- g,* cxz7rb*hz dzd/ng*uhicient 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.