Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the peri(yb 9qq b,fcqt4bo//h odic table or Appendibqy/thbq b/f q4oc(9, x B.

Name several properties of mqbxso9xtmo ;15jg )u* aterials that could be exploited to make a thermometert )s;bx5m 1qj*guox9o .

Which is larger, 1 C ( :woho aox4,o$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equ mvlhho0a675nkps 7 x;ilibrium with system B, but B is not in thermal equilibrium with system C,;7vp7hm06lkon ax sh 5 what can you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminuhefu-2q-85x x,dzo c i ;x tsof5d;;omm riveted to a strip of iron. When heated, the strip will bend. W ot ox; 5e;ioxqzh- m,8cdfu5s2f;dx-hich metal will be on 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 q,/s.pq zv/gk of linear expansion $\alpha$ are $(C?)^{-1}$ and there is no mention of a length unit such as meters. Would the expansion coefficient change if we used feet or millimeters instead of meters? Explain.

Figure 13–27 shows a diagram of a simple thermostat used to control a fsrcu pmqq(f q;yy(3( (urnace (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 furnampsqy(( r c;q((yfuq3ce and how it can be set at different temperatures.

Long steam pipes that are fixed at the ends often have a section in the j,j8 bz ;sd6pu,l-vkhshape of a Uz p,s8kh;6judjv- l,b. Why?

A flat, uniform cylinder of lead floats ins.8y f5 5 f3svifolf1w mercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometb nzyqe6b71u )y l*q4e4 3kdgser is first placed in a hot tub of water, the mercury initiag1dbk34 yl7ueq 46y qseb)n*zlly descends a bit and then rises. Explain.

A glass container may break if)qrc/6 e.9auwfhcl6; (-o vakl-px sx one part of it is heated or cooled more rapidly than adjacent paup(v-9cq x r he.swaklx ;/a)6fc-lo 6rts. Explain.

The principal virtue of Pyrex gs+5kum vkw.97,eoltmage/;la/m ) mrlass is that its coefficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to trm 5ommw/ 7/ eka)gel;+u ta.s9vm l,khe increased heat resistance of Pyrex.

Will a grandfather clock, accu2 cgh; 9nhr 7,gkdnjh,h5n71q ziyj.trate 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 bottom and top to bulge so batso,a wn7qt1 wu+x(8nozhk;,0oqn x (dly the can will not stand up. What ha, 8,sxw0qo7tz( qhtwon x;k(n+a u1o ns happened?

When a gas is rapidly compressed (say, by pushing down a piston), its tempzdj5rty.f3baes0 2e m2htf3o0p8 y-qerature increases. When a gas expands against a piston, it cools. Explain these changes in temperature usit m0e8fj23fyha0dp. yo-3sb2rztq 5eng 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 intb3ux,7 fpp ub +5bt4fcrease or decrease if the temperbbxt7, u fu+p5tp3f4 bature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theory and the qb*uo,l 2*i4z9oizg v wac0f: relation between average kinetic energy and the absolute tempoow ui:vzl*fqiz09cg2* 4,b aerature.

Explain in words how Gay-Lussac’s law followsn7 x:ce*3f ;i ecc:log from kinetic theory.

As you go higher in the Earth’s atmosphere, the ratio o0l p /zdpj hi7/8ah(un ;zwj)df $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed an object musycp28 21anw qbp9rj 1zt have to leave the Earth and never retur cq21zpyr2 na8pw1 b9jn. The escape velocity for the Moon is about one-fifth what it is for the Earth due to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at rv/wd5s g5l-h,gpg)il k xv*0p oom temperature. What can you infer about the molecular s0gv/v li5,pwgx5lh g k*d)p-properties of one relative to the other?

Explain why a hot humid day is far morcb8 rjhc);i6) xld4tze uncomfortable than a hot dry day at the s;rx)l6 )i8hd4 ccbtz jame temperature.

Is it possible to boil water at room temperature (20 :(9ahci12v mkr6 tbgpg8 z j5 /ign8ll$^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the humidity is difmw 3( yby-wj+iferent. Which is more dense, the dry air or the humid air at the same T? Explj(y wbim3 w+y-ain.

Explain why it is dangerous to open the rad.e kwmx, 2*j,yw fzra)iator cap of an overheated automobile e xmwaz . ,efyjr2kw,*)ngine.

Why does exhaled air appear as a littlex.+e a( fsehuj6p fu*, white cloud in the winter (Fig. 13–28)?

  How many atoms are there4w.: tlwph p / ewlj7:.yy;mtk in a 3.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compar5ze3xf(wv7x a e to the number in a silver ring of 57xwz3(vxae f the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is o*e-e lt265e sqr5sdl cf2*r;cq-wg iwften taken to be 68°F. What is this on the Celsius scale?5 eqw tses- 2 *;l6e-gcic*r q2drlfw5   $^{\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 tempera-7no.ngwf ym5wjn3sio w5s,bj k 0c0(tures 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 thermometer9 , rrrpus;0se, the alcohol column has length 11.82 cm at 0.0;ru rsse 9,0pr $^{\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 s7akrh0,f 1z gkjj9 lmo9 e,,wrlabs 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 approximiybc+nd *cqy89t7 9pl ately 300 m tall. E 9i 8pc+ ylqdb*ntyc97stimate how 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, riv9oscd(zv ho6bol m-hm264eb 1ets that are larger than the rivet hole are often used and the rivet is cooled (usually in dry ice) before it is placed(sc m b12zo6 be4 h9ohd6-mlvo in the hole. A steel rivet 1.871 cm in diameter is to be placed in a hole 1.869 cm in diameter at 20 $^{\circ} $ C. To what temperature must the rivet be cooled if it is to fit in the hole?    $^{\circ} $ C

  The density of water at 4 +zxnre04u xl9 $^{\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. Whatcxccmwp i,;y 6))6cexh;9f bt will be its change in volume if it is heated from 30 b) 6y f9ecx)ic pxc;th ;mw,6c$^{\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 100h4htn8a* e8h 6mr7cfm.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 watermln..b;wr* uch n,z l.1k l-qt 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 20 /,y;1k /s) j ai v4nwb3tchlni$^{\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 ai55x1pe m r(*lfq zr;q long, narrow vessel so it can expand in essentially one direction only, show that the effective coefficient of linear expansion is ap *iepq1 q;fx m5lr(rz5proximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the cha-gam2;e kav; enge 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 plato 4, q1mjhhilh a+;(+f z+wd wsop8:yke of length l and width w has coefficient of linear ex,as8lq+m4j ;hw+o zhhyi +o :pwk(d 1fpansion $\alpha$ 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;lf 7a)s u/mgj, $\beta$ = 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 1o)oj)fb+e4wdcsw am s1o * /hmade of brass and keeps perfect time at 1o1wjsd/fom a c e+4hb*sw) 1o)7 $^{\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 thermo.z6cn+ y lj +)v8rkl g1qtn.zqmeter has an inside diameter of 0.140 mm. The bulb has a v..c+y)z+vn1q z n6tql8 kglrjolume 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 rotating about ibp qpc .y iz2,u+. mu/6+u9qrxyq*bvq ts axle on frictionless bearings with angular velocit2+purz q9bxvi uuy6y,.+mq cq*b / .pqy $\omega$ = 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:dh8e-:t17 fp25prwxgkki 8n+ze q yt when at 15°C. How much stress is required to keep it at this length if i ekrt-zh:gyk88 dweq 5tp: 7x+2nf1pthe temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-sectional area 0.042nsi hr( i)yec-0ly:p1$m^2$ 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 diameterlx1l)jpx,tw fg+wr/h22g . kk 134.122 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 Kelvin scy6,bw:6snqsa 0w. pzyale:
(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 Fakj iozi d b3h:xl/n.9/hrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun are about 4vknowbwhg7y, e((+1sjox rr :g3r89ix1 ayr/000$^{\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 combuwnay(ujieo0)vy ) u.pqz0: : estion engine, air at atmospheric pressure and a temperature of about 0n0pe z (u)a)uyvy o:wejq. :i20$^{\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 tvu;40x(f yx q4a *ohqthe ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of nit69rp z+vq i:firogen ($N_2$) 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 nitrogen:t ey +w1ji-to/h3rd(nmku*v ($N_2$)
(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 heliu43ohq rnn -y-tm gas 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 cobf (dgjd so 3t6n5nx3 fq7)hm4ntainer holding 105.0 kg of argon gas at 38 b dgf6sq5mxo3t jn(3n )df47h5 K?   $ \times10^{ 8}$Pa

  A tank contains 26.011 enayb m-3e7 v9uj8oddi0nw 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 yd((ufnq7+p y76zi yjlift by heating the air inside the balloon, which makes it less dense than the air outside. Suppose the volume of a balloon is 1800yiy(nqyj7z+dpf(7 6u $m^3$ and the required lift is 2700 N (rough estimate of the weight of the equipment and passenger). Calculate the temperature of the air inside the balloon which will produce the required lift. Assume that the outside air temperature is 0 $^{\circ} $ C and that air is an ideal gas under these conditions. What factors limit the maximum altitude attainable by this method for a given load? (Neglect variables like wind.) $\approx$    $^{\circ} $ C(Round to the nearest integer)

  A tire is filled with air at 15(5qq6;3m. fpk/dbsois*hsjh $^{\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 a v ,a6yzmh-z;*js2xha8 hy tq9t 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 k lr8l k+s5rc9escapes a child’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 uo7u-8w ot0 vyw/ttc5q1m f9jof 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? How ma2yvwxlaj24+ s rn)ns 1ny molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of ( jhi/57y xii2ja) 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/wzu:f;pk+jq(c5 s7amxpx- 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 y lohfep*jh+va b6+4w 83pb p4vs94kwd ou inhale that were also in the last breath Galileo took. [Hint: Assume the atmosphere 4dwje94p6pbab4w klh 83v ++vosfph* is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of an oxygen molecule 9q:j cf kho1pp76zbq ,at STP? phk bfqc:z167o, jpq9    $ \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:(pcmr 1(gnunac8qv7 7bg sv , of helium atoms near the surface of the Sun at a temperature of about 60007b8nrvs cm1 7un :(q pc(a,gvg K.    m/s

  By what factor will the rms speed of gas molecules increas7dxc rbnh6 )0ne if the temperature is increased from xhr)nnc06d7 b 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 speedsb wlh2f zc50-j, given in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and b-fj52 hlc0w z8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molec 49ro glg5jj4sules in a gas at 20.0 $^{\circ} $ C is to be increased by 1.0%. To what temperature must it be raised?    $^{\circ} $ C

  If the pressure of a gas is doubn .zx,sy v 6x9pktty25sppo2 2ygt-b8led while its volume is held constant, by what fa6xkp,5yot 22 bg.9vsx-zptpnsyy 2t8 ctor does $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is given bqws(yny,s: 9v y $v_{rms}$ = $\sqrt{3P\\rho}$ 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/skmjm3 f y)x j/5d*yu ratio of their rms speeds is equal to the inverse ratio of the square roots o)3 y5xsymm /kjjufd/* f their molecular masses.

  What is the rms speed of nitrogen m. do,/6ftit bmolecules 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 moleculej( p 8hopk6hu h0pt+ y/)f68ox(mwb aj 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 between nitf5cabw/jl61 er6i 6 sp b8vt60:bggg crogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose moleculi4.hu5;kr0lrdygg5ysr9 : x lar mass is 89 u in a living cell at 37s 59.r 4u y0lg;rykgir:hl dx5 $^{\circ} $ C.    m/s
(b) What would be the rms speed of a protein of molecular mass 50,000 u at 37 $^{\circ} $ C?    m/s

Show that the pressure P of a gas can ber*psns :f) f+e 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 ur 0p*t3hoksm/zki d w a8w*v32ranium, $^{235}$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 phase+t+vzlj zs 3h ye.ld+e*b-0zq(vh.g rs 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 awl0o45 1qvfrz9oq82rh 1uj uf f4ebcu17oo (ind the temperature is (a) o7o o8uv hlf12wzf4f 5e uicor0 qq94(1ub 1jr90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity is 50%k.9x4y poi p6b on a day when the temperatuyx 94 pokip6b.re is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where wate0p, ,0kpuqhhl l oxxvwuc*we/),. j+v r boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains i j7ywl9l9bak0jl9vm-k f72nus 0.72 atm, estimate the temperature at w7j f2a9vlk0-uk nwjll y9m7 b9hich water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a y:j66r4iku rn/jm3ekday when the partial pressure of water is 530 Pa and nui6k6m3 /ejj y4k:rrthe relative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the tem b7sz( bna2ig3oa c8+gub7 jj)perature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a 1dqjv j2m ,w-apressure cooker if the water is boiling 1dmaq -w vj2,jat 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 roo;kh ch4bq(6,gu :pb7h ajffz1 lyp2t )m of volume 680$m^3$ at 25 $^{\circ} $ C is 80%, what mass of water can still evaporate from an open pan?    kg

  Air that is at its dew point of 57ef+) ao; )ggk y;dhfw $^{\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 xnp7;h9bf) h 3 ixvkt1a glycine molecule (see Table 13–4) to diffuse a dinki9 vfht7x; 1 p3b)hxstance of 15 $\mu m$ in water at 20$^{\circ} $ C if its concentration varies over that distance from 1 mol/$m^3$ to 0.4 mol/$m^3$ Compare this “speed” to its rms (thermal) speed. The molecular mass of glycine is about 75 u. t $\approx$    s ([color=rgba(0, 0, 0, 0.85)]Round to one decimal places) $v_{diffuse}$    $ \times10^{ -5}$ m/s
$v_{rms}$    m/s

  Oxygen diffuses from the surface of insect18zf0q/ kkpksm k 6d-fs to the interior through tiny tubes called tracheae. An average trachea is ab 1q0k8md-6ff szpk/k kout 2 mm long and has cross-sectional area of $ 2\times10^{-9 } m^2$ Assuming the concentration of oxygen inside is half what it is outside in the atmosphere,
(a) show that the concentration of oxygen in the air (assume 21% is oxygen) at 20$^{\circ} $ C is about 8.7 mol/$m^3$ then $\approx$    mol/$m^3$(Round to one decimal places)
(b) calculate the diffusion rate J,    $ \times10^{-11 }$ mol/s
(c) estimate the average time for a molecule to diffuse in. Assume the diffusion constant is $ 1\times10^{-5 } m^2/s$    s

  A precise steel tape measure has been c bb9cd.qpiw6; 8q5hym3bt v3walibrated 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 tapen7ew yd5z+v4 c measure 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 Pyrex measuring cup was calibrated at normal room temperature. Ho h-a lvh02b0rmfneu*7 qej 2r6w much error will be made in a recipe calling for 300 mL of cool wate-vr2h0 b ul2a e7*0jfqner m6hr, 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 many ba)z fm (ot.jdkgl d4h/7lloons have been blown up, the gauged(hz /kl 4otjm)7gd.f pressure has decreased to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air molecules in a room of length 6.5 m, width 3.wng2wc8f,n7s0r p/ ia 1 m, and height 2.5 m. Assume the temperatsnrn70 fg a8,ipwc2/wure is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density ofq*vj5n yi2(fuh9 l*;qc 2dzd p 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 attainabk/g 4fyq1 qtw+le using the best available vacuum techniques is abo1gq4/ytf+q kw ut $10^{-12} N/m^2$ At such a pressure, how many molecules are there per $cm^3$ at 0$^{\circ} $C?    $\frac{molecules}{cm^3}$

  If a scuba diver fills his lungs to full capacity of 5.5 L when ),wp rbnnpai* k2vn;4 10 m below the surface, to what volume would his lungs expand if he quickly rose to the surfa p*p2;nk)bw4a ,innvr ce? Is this advisable?    L

  A space vehicle retu -g4ekd; /6 8hjlplkxs ctuu31rning from the Moon enters Earth’s atmosphere at a speed of about 40,000 km/h Molecules (assume nitrogx1p4ethd lk -3uuj/sg8k;cl 6en) 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 upon reentry.)    K

  The temperature of an ideal gas is i5u +.oi mtz tgnk51na(ncreased 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 jj(,vg5meny./r x8to . xcf(lof 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 atmospheri-8dp )jko cok*c pressure at the surface of the Earth, estimate the total number of air molecules in the Earth’s atmosj-)*d opkc8ok phere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contained in 8v56kap p emeznu.47za 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 pressu 97irev9l5qe7xrv5gc+g m+t kre = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmrt+ q579ev r i xklcm59+gvg7eospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liquid mer 6ze3vekt5s7hcury 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 m eu -+ o1tzm l1ons8 id8:ek0cno66mgat 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 arouwpy.4 k9lo-nend 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 omityn7fl 8sr rya8 p8/+ j3-jfnto 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 in thw 7,yqcyzf 4a/e 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 oxj:k va/a06 km4n1zwaf 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 is3.fe3uv )ieq;mv*tm w $ 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 suspen;lmy1; uofz26;yjvb c0oi -z ided against gravity by tennis balls thrown vertically upward at it. How many tennis balls per second must rebound fzz; c2m;-bo;iuvyj 6ilfo 0y 1rom 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) bubble of -i8ndig 0 rhn 3/teg,mair from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the air behaves as a perfect gas. How large ii hdei8 gtr3gn,n/- 0ms the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure in the air on the following two daywz1ki6s68 fb ms: 61fi 8mzk6bws
(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 u;/3sr elny71:e g xloin the density of iron at STP, and when it is a solid deep in the Earth where the temperature is 20:lnxr1g ee; 7lsy3uo/ 00$^{\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 shgwasl2 1kbwf,a +tl5 4ow that, for an ideal gas at constant pressure, thk14s lwf ltw5ag +b,a2e coefficient of volume expansion is equal to $\beta$ = 1/T where T is the temperature in kelvins. Compare to Table 13–1 for gases at T = 293K (b) Show that the bulk modulus (Section 9–5) for an ideal gas held at constant temperature is B = P where P is the pressure.

  In humid climates, people constantly dehumidify their cellars tola) a wuo;s-/g a8ay *cfk;2zl prevent rot and mildew. If the c); uwlo*l zsa y8ac- f/;2gaakellar 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