Which has more atoms: 1 kg of iron or 1 kg of aluminuwz is63q6y :anm? See the periodic table or366 s yi:wqazn Appendix B.

Name several properties of materials that could be exp6 v +fv5ctltj mdz99tn9 ;wi:vloited to make a thermomet5:z9 9c; v6dvjw+ni9vtl tmft er.

Which is larger, 1 C;;1 u0ts cduyq $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B is not in thera fn( 5c1xe , 3-bzw3eyb7csetafz(q.mal equilibrium withb5etnf c1f-aqx33a(y7ewzs (z,bce . system C, what can you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of ;(tu: 8vfmnjraluminum riveted to a strip of iron. When heated, the strip will bend. Which metal will be on the outside of the cuvrumn ;:tfj(8rve? [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 linea vg5:n4 bvq9b/f z2sh,dj mvh;rez8pc (ej7l+ r 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 furnau;7bu0r2brb-reekx j+1 f5z;o wi (wv ce (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 co2re+ 1z-bre0(; bvju5uk;wbof 7x iwrntact 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 shape f7( vaf ckf/fr.tl0pm29 x)nq of a fcl0( ft9)7.v fkrxf aq pmn2/U. Why?

A flat, uniform cylinder of leadxe9e-e 2s;+ar*q p bpp floats in mercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometer is first pltl ,bato s897.*mj hleaced in a hot tub of water, the mercury initially descends a bit and then bs.* j 89loela, 7tmhtrises. Explain.

A glass container mayq.8eq;rqmkr6 v-(by - gqijpss 1 (u1w break if one part of it is heated or cooled more rapidly than adjai(pg (r1qq1 q -vkj6bw-r ss.eu;8 myqcent parts. Explain.

The principal virtue of Pyrex glass is that 3jdpmch9h7jwdc5z ,(8oof0 2fs ie b2its coefficient of linear expansion is much smaller than that for ordinary glas(8jd op 2c, b2zwj3id9 7co5shfefmh 0s (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurate oi;-f0 qxnr 1gat 20 $^{\circ} $ C, run fast or slow on a hot day (30 $^{\circ} $ C)? Explain. The clock uses a pendulum supported on a long, thin brass rod.

Freezing a can of soda will cause its bottom and top to bulgho/r.0v -f;b pvsbf8ee so badly the can will f-0 bhro v8fp/e; vb.snot stand up. What has happened?

When a gas is rapidly ch 5)qky k*0yweompressed (say, by pushing down a piston), its temperature increases. When a gas expands against a piston, it cools. Explak)h5 w0*yqeykin 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 ali gba80xy5-submerged in water increase or decrease if the temperature isga-xlb50a iy8 increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetew)it 6f2,wz9 g- :qu:uafv evic theory and the relation between ave-t fqe:iu)vew:a 6gfuz92wv,rage kinetic energy and the absolute temperature.

Explain in words how Gay-Lussac’s law follows from kinetic t;li4 wc .8 0ad(r47hksw8 eulntkfyl1 heory.

As you go higher in the Earth’s atmosphere, the ratioy pv ;6yhnr),kd 1o3xp of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed an object must have to)fh(m5ph43dhkh )sn d / m0ele 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 atmospherek)dh (f0eh/4 m)3h nphe5lsmd .

Alcohol evaporates more quicklp s0ibvs)bh 1:y than water at room temperature. What can you infer about the molecular properties os1s ivh0:bpb )f one relative to the other?

Explain why a hot humid day is far more uncomfortable than a hot drrr(4fkeq ha* 5y day at the same temperqr5*4fer(ka hature.

Is it possible to boil jf7(spn r7d3w +kx-(t da l//bfs;t-q /odr cawater at room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the humiditeev9)e(m1yz*xq) / r; k6i u5cyaqxlpa5;dn ly is different.()l y5a;vqpm e l)6ierxdkz5ay*e; q/u x19cn Which is more dense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap of an overheated aclw*jrqb3 ceb 2we /47utomobile enginebe*bw7q cwcj 34rl /2e.

Why does exhaled air appear as a little )/s:n+atq u xx a:tc0pwhite cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram copper pge-/m:zq4+d4tnptt i) km7t cenny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring comgi7 /q4kg9l6m 6wdo, b b1vciec fa-h3o*;uwkpare to the number in a silver ring of the same maso o* wa 6q/mi-k61gc4i c,bghe 3l u7v9fd;bkws?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often ,nxqsw2 x9 mbvhk5j3-taken to be 68°F. What is this on the Celsius scale?w23 5x9qhkbnm, x-vjs   $^{\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 recordxt8-wk 95o qkxed 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 alcoholnz0ilp4yuc, 7 cct7e/ column has length 11.82 cm at 0.0c nc7iz/ 04tl uec7,py $^{\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 bu:;wtr o9 pi1yuilt of slabs 12 m long (20 $^{\circ} $ C). How wide should the expansion cracks between the slabs be (at 20 $^{\circ} $ C) to prevent buckling if the range of temperature is -30 $^{\circ} $ C to +50 $^{\circ} $ C?    m

  Super Inva$^{TM}$, an alloy of iron and nickel, is a strong material with a very low coefficient of linear expansion [0.2$ \times10^{ -6}$(C?)$^{-1}$]
A 2.0-m-long tabletop made of this alloy is used for sensitive laser measurements where extremely high tolerances are required. How much will this table expand along its length if the temperature increases 5.0 $^{\circ} $ C? Compare to tabletops made of steel.   $ \times10^{-6 }$ m    $ \times10^{-4 }$ m

  The Eiffel Tower (Fig. 13–29) is built of wrought iron approximately 3v9l0mzzphi m*g)67cs ae9/n a00 m tall. Estimate how much its height changes between July (average temperatur *c m) ia/n76z0slmgazv9h ep9e of 25°C) and January (average temperature of 2 $^{\circ} $ C). Ignore the angles of the iron beams, and treat the tower as a vertical beam.    m

  To make a secure fit, rivets that are largmon,d. oo *4lp,u(-uccou-k)ap1gst er 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 in diameter is to be placed in a hole 1.869 cm in diameousgoc*du a,c-. m,up1o4-kn(o l)tpter 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(hs i9gik89 xr z ks3y*viapa7t5v m4, 4 $^{\circ} $ C is $ 1\times10^{3 }kg/m^3$ What is water’s density at 94 $^{\circ} $ C?    kg/$m^3$

  A quartz sphere is 8.75 cm in diameter. What will be its26g8 okem1s,ag7,tnc r dyt( q change in volume if it is heag,8gms dto62(cnr 7,ae qkt1 yted from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350.0 mL of water at 1 /z1*i wl-ccpw00.0$^{\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 of w3cy:issi 2. * g8nxraeater at 20 $^{\circ} $ C completely fills a container to the brim. When the container and the water are heated to 60 $^{\circ} $ C, 0.35 g of water is lost. (a) What is the coefficient of volume expansion of the container?    $ \times10^{-5 }$ /$C^0$(b) What is the most likely material of the container? The density of water at 60°C is 0.98324g/ml.

  (a) A brass plug is to be placed in a ring made of iron. At kswfy56pm pvzn7da *)v (d-*k20 $^{\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 expif zkrx4 *fxm;i.:kh2 f -n sm4b89eyiand in essentially one direction only, show that the effectikf4 m* i;:sf yibk4r zihn2x-mf8x. 9eve coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the6o /vfmy f1xib/4w3kreq y4p 6 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 platv 8zj iba)+hi 7i6gb+qe of length l and width w has coefficient of linear expansh 8jb+6q+ iib a7v)zigion $\alpha$ 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 sol1*irl-*usu, jv go6gsid, $\beta$ = 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 5 n90 xmz xw73nut)ph 4bii bo 90i,sf,lvujc:is made of brass and keeps perfect time at 17 : bx74mhvlw x,nni0fzuts 9cu3oji,b )95i p0$^{\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 o:zn/ sts+j-cdiameter of 0.140 mm. The bulb has a volume of 0.2on/tjc :ss-z +55 $cm^3$ How far will the thread of mercury move when the temperature changes from 11.5 $^{\circ} $ C to 33.0 $^{\circ} $ C? Take into account expansion of the Pyrex glass.    cm(b) Determine a formula for the length of the mercury column in terms of relevant variables. Ignore tube volume compared to bulb volume.

  A 23.4-kg solid aluminum cylindrical wheel of radius 0.41 m is rotating about /r -i+h lqkonu9 ms+,aits axle on frictionless bearings with angular vel ,la-misr+/onqk + h9uocity $\omega$ = 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 d llu9(grvzc ((esired length when at 15°C. How much stress is required t (u(lrgl9zcv( o keep it at this length if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-bea7t tn xnep lk.yb7 3xj0k32(sfm 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 134.1; 6s*precc jvjjb05laf) ni z;px6l74 22 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 temper143 p mn9zcxlwatures 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 temperature on the Fahrenheit scale? 9h(r0+ g:us:bz e/muy u,us7 qvpj k+d   $^{\circ} $ F

  Typical temperatures in the interior of the Earth andae qnbsym)a 00(q( c qg0djc3+ 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 engii(vg;nrwk0 a7ne, air at atmospheric pressure and a temperature of about 7arn kg wvi;0(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 th6a :bv0wl/ iqle ideal gas law.    kg/$m^3$

  A storage tank contains isoq 42rs6j ,gp:id/c q0 kfm*21.6 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 contains 18.5 kg of nitrogb vb(a(mkp ,s)en ($N_2$)
(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 at xj z9ux: w*ca)+szfj*j+m g8 z10.0$^{\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 con /ja8 ezz*kgt7:vlx (atainer holding 105.0 kg of argon gas at la(8k axzgvtj*7z :/e385 K?   $ \times10^{ 8}$Pa

  A tank contains 26.019yv ms 4t5biy7ect o;dr*1tni xcl.+ kg 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 h7mve p roiw7o/q*-3jbv i5c; teating the air inside the balloon, which makes it less dense than the air outside. Suppose the vit 7o*-3cv5qp ebm; / vir7owjolume 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 va26*v jxbxd3co /m(3l +mwkzwe 4sy; *u;h roair at 15 $^{\circ} $ C to a gauge pressure of 220 kPa. If the tire reaches a temperature of 38 $^{\circ} $ C, what fraction of the original air must be removed if the original pressure of 220 kPa is to be maintained?    %

  If 61.5 L of oxygen at 18.0 o zvzc;r 9,l-n$^{\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 uo/e ftq-91tl2jp v :ghand at sea level and 20.0 $^{\circ} $ C. When it reaches an altitude of 3000 m, where the temperature is 5.0 $^{\circ} $ C and the pressure is only 0.70 atm, how will its volume compare to that at sea level?    times the original volume

  Calculate the number of molecules 0traa7 b:0isb/ $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How many mo)h6s vo njk6l5lecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a ;l;-+cawyhmk) 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 volum 0dyiszv.bvuj38x 5 d*e 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 air are in each 2.0-L breath you inhale ts he74;fi(nd2mpjwnyma8c f 6-/ cuh2hat were also in the last breath Galileo cepf un8-/fwda7hsj6h m c(ni2 4;2my took. [Hint: Assume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of an oxygen mole:w-g zuw-phv8cule at STP? hvwg8: -zu-w 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 of the Sun at a te ag ei/3n7o: 0svjznq,mperatuz70/iaeq3 g s j,n:novre of about 6000 K.    m/s

  By what factor will the rms speed of gas molecules increase if the tempe- lk-0kdyuyy33mwq w d8j/f.ul :aegvh( u5i.rature is increased (avuwduyyey w .kljf: m qu3-k-ih50.3gld8/from 0 $^{\circ} $ C to 100 $^{\circ} $ C?   

  A gas is at 20 $^{\circ} $ C. To what temperature must it be raised to double the rms speed of its molecules?    $^{\circ} $ C

  Twelve molecules have the following speeds, given in unit9 obri+)ie,gq s of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calculate the rms spe )g,broii9e +qed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at 20.0rv5j 62uoi 26 kchianb6z ;mg, $^{\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 constantr -p7r/ k;nb2b 3txf4at 8c6c6z xkobx, by what factor dob7kor txc6p3 -zb64 /xnra;bcfk 8x 2tes $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is given bqj2sm mqd 3;t4z.(ej iy $v_{rms}$ = $\sqrt{3P\\rho}$ 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 of tq gkjn74oio80o8in w7 heir rms speeds is equal to the inverse ratio of the square roo gowjqk8i7 7on08oni 4ts of their molecular masses.

  What is the rms speed of nitruiza/h egbv8jt;0u; 0fj)scec nl4:* ogen 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,t fpo6;(ppnr sxh7jjp; )o*x 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 betweea6:hfe ci/1 zin nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an a 6qin5(7ywvv wmino acid whose molecular mass is 89 u in a living 76 n w5wivvqy(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 c-c1*;kietm8j;7 cpt v dh;qodbm83s ban 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 ura8, ci:u hcihx;nium, $^{235}$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*-7zz fn8avpy6xhc/( m cx3 qx, 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 t5ipqzs:,mh r*2p7( rg2 *gc hxap6y mxfyv+( zemperature is (a) 90rxph6srmv hp,fmxi7*g2( (:qg+5 y* apcyzz 2 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity is 50% on a day when th*1tj*g,igdpmb+g ,myhc d3eabt22 a0e temperature is 25g*1mp+,y,ia 2bg 02 hj 3bamtdg t*ced $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a placpj f;5 c kvl glk0vlt8p/y));ze where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particula6 - q ha-gbs2h*+ez +jgvyz+dur place in the mountains is 0.72 atm, estimate the temg++ zeqhh v ja2ysd-bz6u +-g*perature at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperatur *qzbl::kv 03pv/h hpgiil,3f e on a day when the partial pressure of water is 530 Pa and thv0z3 qi/,pgpib vf*lk: l:h 3he relative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the temperaturewuqa6;wm zl *f6k*w ,v is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressu,lx* . :j8sm +hizzhtr9pme/2/wlbv ure inside a pressure cooker if the water is boiling at a temperature of 120 8 lm:9l ut ipe,h/wr*z vhms+/b.j2 zx$^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room of j g fch7,6xed*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 poikew sg4)dq-/ ont 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 ar m;k0mr8d(u q;-oi8a,qubri distance o,d (88q 0 ia umq;omirkrbu-;rf 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 interc+.(5,abbsonwf 7e xy ior through tiny tubes called tracheae. An average trachea is about 2 mm long and has crosss 7bnb,ox.5f+aecy(w -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 measurhk+ 9e;ci ffw7e 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 hig.:g4iib)r xo 8vb :wl+r ut1gerc9 *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 temp44 udcff*3c ubcegk(3erature. How much error will be made*gfc( e4fbuk4 3ucdc3 in a recipe calling for 300 mL of cool water, if the water and the cup are hot, at 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in a helium gas ce nx;:r 9)cu83n(i-dr t(a ee:v ue1whwcg ey1ylinder is initially 28 atm. After many balloons have been blowr9agcyn)wn x : wt1vu3;ue ( d:8c-ihe1ee(ren up, the gauge pressure has decreased to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of a;a wv)xqi2x5 4r9fbhxir molecules in a room of length 6.5 m, width 3.1 m, and height 2.5 m. Assume th45 rxq);ivb2xx whf a9e temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density ofv5eu (slt71nw h-8ljl 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 attainable using the f ivgx80x-mh:k( ny0n best available vacuum techniques is abov0-mn:xyhnx ( i8k 0gfut $10^{-12} N/m^2$ 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 ha::8 na 6lfjatis lungs to full capacity of 5.5 L when 10 m below the surface, to what vo: fn68a jatl:alume 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 atmosphere at a speey8y k7u ,zpw:me1s4 eed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this speed correspond to what temperature? (Because of this high temperature, the nose of a space vehicle must be made of special materials; indeed, part of it does vaporize, and this is seen as a bright blaze up7 e m,1:epu4wyeyk s8zon reentry.)    K

  The temperature of an ideal gas is inc/2c6hf2 e-/jugtaarv reased 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 volumez a-a(bli+pdz58m 7ps of 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 surf;h gds(, 9xfoiace of the Earth, estimate the total number of air molecules in thego;(,dfhi x9s Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules containo+dha-e+ 3fl qed 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 = 20tq of.-,6ih ve00 psi (13,800 kPa) and at T = 259K How long will the cylinder last ifq, f .toi6ev-h the flow rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats inwj uh1nb z45,h)zm +ci a bowl of liquid mercury at 0$^{\circ} $C. (a) If the temperature is raised to 25$^{\circ} $C, will the cube float higher or lower in the mercury? ----待选择----lowerheigher 
(b) By what percent will the fraction of volume submerged change?    %

  The density of gasoline at+ z ;pg)piq5qp 0$^{\circ} $C is 0.68$ \times10^{3 }kg/m^3$ What is the density on a hot day, when the temperature is 38$^{\circ} $C?    kg/$m^3$
What is the percentage change?    %

  If a steel band were to fit snugly around the Earth’pcu:mgsb u-;i9f( f 8e.mn1d/l +e zsis 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 l2;/ki t:dr.sff u/l conto a glass jar at 20$^{\circ} $C. To help open the jar, it can be placed into a bath of hot water. After this treatment, the temperatures of the lid and the jar are both 60$^{\circ} $C. The inside diameter of the lid is 8.0 cm at 20$^{\circ} $C. Find the size of the gap (difference in radius) that develops by this procedure.    cm

  The first length standard, adopted iz01ua- jxwykv;b1 d 3on 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 prs-3*0qpa uo0t7p i hrmessure of 195 atm at 20$^{\circ} $C. The volume of the tank is 11.3 L.
(a) What would the volume of the air be at 1.00 atm and at the same temperature?    L
(b) Before entering the water, a person consumes 2.0 L of air in each breath, and breathes 12 times a minute. At this rate, how long would the tank last?    min
(c) At a depth of 20.0 m of sea water and temperature of 10$^{\circ} $C, how long would the same tank last assuming the breathing rate does not change?    min

  The escape speed from the Earth bdvi x *8 ha2leke/)-kis $ 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 gravizd gvm6 - t))a7mjm9qlty by tennis balls thrown verticqv j m6m) dmlg97t-)zaally upward at it. How many tennis balls per second must rebound from the lid elastically, assuming they have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter (sphericaln.s ak9vcj r)6) bubble of air from a depth of 14.0 m9 k6a )sn.cvrj in a lake. Assume the 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 wa- 1pz )lm9v.o +aeaehyter vapor pressure in the air on the following two days: ylho.v1ame)p9 a-ez +
(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 whell-f34*e5x2usgph z :go kn(qn it is a solid deep in the Earth where the temperature is 2004q(*n 3 xegflpo-h2kgs5l:zu 0$^{\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 v*3u1o6*ohlumlj 7ze law to show that, for an ideal gas at constant pressure, the coefficz37u m* l ue*oo16ljvhient 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.