Which has more atoms: 1 kg of iron or 1 kg ofq yy)bd( yhm6zm/4 ;hni7 npyu+8exd7 aluminum? See the periodic table or zqd+6hnm4h7y7yyb(e u/)dp8mx;iy n Appendix B.

Name several properties of materials thkl .k9ygp: d0eat could be exploited to make a thermomet 0:ky 9dkpg.leer.

Which is larger, 1 C o jmv x+)h8l/;5c7 k gqqz8t5me+jsub$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrrkmggzxe 4 (jshpwt5*:,q y.:ium with system B, but B is not in thermal equilibrium with system C, what can you say about the temperatu.q(ypgjs5k*xem:t , : z g4hwrres of A, B, and C?

A flat bimetallic strip con2pcy)by4n (i ysists of aluminum riveted to a strip of iron. When heated, the strip will bend. Which metal willyb4n)(iy yc2p 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(2c )xpne,xfg. t w4nna7sv p6 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 diagraminml**av;8or of a simple thermostat used to control a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The e;**irav 8o nlmlectric 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(*uj(vl p;/+wk iixpatd0 l;h the ends often have a section in the shape of a U. Whlxu+;j ;pl(div w ht/*pk0ia(y?

A flat, uniform cylindel/ 5y5a) gqw3i*l ddvyr of lead 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 placed in a hot tub of water, *kdz (eln+o.c the mercury initially descends a+dlc.nek *z( o bit and then rises. Explain.

A glass container may break if one part of it is heated or b; vfv1 cf175sqxx - h.2(bfjqje 3djucooled more rapidly than adjacent pa7xbf q 2s;v cujex(vf- fb1dq315hjj. rts. Explain.

The principal virtue of Pyrex glass is that its cop, 4(ubgt9;3xudka2*ernn6sqcki 9oefficient of linear expansion is muc iopn unr,a9b 4uk gq*tex;3ck2s(9 d6h smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accuratok-,-cox4 qmf.ud0 7f,oj jpz+x )cmie 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 71sj g2rr(sy5ws n6 rxits bottom and top to bulge so badly the can will no7rss56 12rr(jxysngw t stand up. What has happened?

When a gas is rapidly compressed (sbzrot oql:dx,+ rw 6yp(4;;dfay, by pushing down a piston), its temperature increases. When a gas expands against a piston, it cools. Expla:;; wof (do tpd 6y+lzr,4qrbxin 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 submk0a870qlco d8l0 fnp z7wzom0erged in water increase or decrease if the temperature is z8om7c fwn0lo0ap 0 kl 8z07qdincreased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theory anc*c:o qjtx n8 +y;/tskd the relation between average kinetic energy and the ao; /ccn*tqtsjy8 x: +kbsolute temperature.

Explain in words how Gay-Lussac’s law follows from kinea. zqz+dsk(0 rtic theory.

As you go higher in the Earth’s atmosphere, the ratw.o c9/yuekiqka(;yc,sr 3 ,g io of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed an objewuxw888fyz b: ct must have to leave the Earth and never return. The escape velocity for the Moon is about one-fifth what it is for the Earth due to the Moon’s smaller mass. Explain why the bf8 xz:wu8w 8yMoon has practically no atmosphere.

Alcohol evaporates more quickly th.p 6ugnt 3gs2m6-ccwn an water at room temperature. What can you infer about the molecular properties of one relw-66pu nn gg.m 2sct3cative to the other?

Explain why a hot humid day is far motju :6tv(n4u ire uncomfortable than a hot dry day at the tiv4 :u6njtu( same temperature.

Is it possible to boil water at j *ed+/h1eqc qg5ovl2room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is theau7pr 40mt+m 4booa nmc+9 kr8 same but the humidity is different. Which is morem r740km+t8a 4boaumprn o +9c 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 automob8-z26w wl.wpf aann2a ile68 ww2pa aln. 2-znafw engine.

Why does exhaled air appear as aq*h4/wv+ny ,hhp01fe pa9tyo;2eexa little white cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram copperx hj )nq*1n,za55nt vq m9z ja;:2tcfi penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ri)d / g8d-.3rv3j02hy(ekoji7 jecsncpcid 1xng compare to the number in a silver ring of the sjgphn3c8k3j / 2cdsore1 - 7.iivdjd()x0y c eame mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What ial5ysv kgc sd827)ve62cn0 zc s this on the Celsius scale?cevcc5 2g6 07vy)8dazk 2lnss   $^{\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 recov tu4v 9:-xyjp1z*mcvrded 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 alcohol column has length 11.82 cm at kmmdve9j; cn)w8uw ;9jw 70wr 0.k9w; )mdwm;jn w09 ecr87ujvw0 $^{\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 ovqj):xx po92ghx b d9ya: )fo4f 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–gj*v xwq3v l2;29) is built of wrought iron approximately 300 m tall. Estimate how much its height changes between July (average temperature of 25°C) and January (average temperature ;w* 3xv2lgqjv 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, hu-3ch lh7ch*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 1.871 cm in diameter is to be placed ilu7c*hh chh3 -n 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 ltr8d lt,m(b dpi l;/-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 its change in vom+hpk7/ gv6ttcuyt2: lume if it is hehu+ tyg:p/v 62tk7ctmated from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 35ypt 6jwb(u2.g0.0 mL of water at 100.0$^{\circ} $ C. If the temperature decreased to 20.0 $^{\circ} $ C, how much water could be added to the glass?    mL

  It is observed that 55.50 mL of water +7nq(dr+ aamj ajoav.),(7t+ yiv vox 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 mbk(u. jzt9 o6p16ky hvade 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 essentially5md4m2 f;hkg -zoje4us;. k zv one direction only, show thskdkzmg2j;z.fu5m4hv oe;4-at the effective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change ad;eq3nmk0p 4s wr9p( in the density $\rho$ of a substance, when the temperature changes by $\Delta$T is given by $\rho$ = -$\beta$$\rho$$\Delta$T
(b) What is the fractional change in density of a lead sphere whose temperature decreases from 25 $^{\circ} $ C to -40 $^{\circ} $ C？

A uniform rectangular plate of length l and width w has coefficient (9.vapvqzhq u,4 q sjgni/;;p of linear expansionzv(qgu;hs/j n,v.q9a qi p;p4 $\alpha$ 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, xo+;zrhh) g)h osc,sw xh vxko3 5/:c*$\beta$ = 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 m-ypn. h,b0f r)r - ispe*6iuxdade of brass and keeps perfect time at 17bnxp,-pr6u e ).hri d*i -y0sf $^{\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 diam ip ok.:xcgi w7j(+ aa;(imv.seter of 0.140 mm. The bulb has a volume of 0.255vigmco+k( ( x.ja ap.ii;w :s7 $cm^3$ 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 9nb+9rdx5i3ck- uscj is rotating about its axle on frictionless bearings with angul3 kn5cd+x sr-iubj99car 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 stecg+tyyo-v b;4 rj) zr- 90ut3tb p6tsress is required to keep it atej 3+-9 6;ps o0-b4uz)tbytv gycrtt r this length if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beammx xb2yzrz ** :;e1dox6ose) g9jgj 3q 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 131ahpw.a8 zh(1xek-),enwas h t88lfq4.122 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 sd g6 i5g1gba ss6es3c:cale:
(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 tx qx+c wr5n9/ho;yr)pix(/ mzemperature on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior op mlvhj 5,bi7ul9v//mf the Earth and Sun are about 4000$^{\circ} $ C and $ \times10^{6 }$ $^{\circ} $ C respectively.
(a) What are these temperatures in kelvins?    K    $ \times10^{ 6}$K
(b) What percent error is made in each case if a person forgets to change $^{\circ} $ C to K? $\approx$    %(Round to the nearest integer) $\approx$    %(Round to three decimal places)

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

  In an internal combustion engine, air at at0wqk/ oj(h.osmospheric pressure and a temperature ofwsh.j 0(o/qko about 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 usingx4od g+fta.cm. ;71py/l4b cq4w iqga the ideal gas law.    kg/$m^3$

  A storage tank contains 2oyq)zup(dgxv/*/ u s: 1.6 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 containskjt:d:uf8 .wny qsvfuy2( yy2w0m p, - 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 at 10.0 *dbg2b96zf yftz /ka9$^{\circ} $C and a gauge pressure of 0.350 atm, (a) calculate the volume of the helium gas under these conditions.    $m^3$
(b) Calculate the temperature if the gas is compressed to precisely half the volume at a gauge pressure of 1.00 atm.    $^{\circ} $ C

  What is the pressure inside a 35.0-L container holding 105.0 kg of argon;kh4hm nxmom 9t- et/qw7)8rb gas at 3xt /7k-hm wtn)qe mm9bo 4r8h;85 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 mn h iuoig qoa93t4-4yu(m, k4kg of $O_2$ gas at a gauge pressure of 8.70 atm. If the oxygen is replaced by helium, how many kilograms of the latter will be needed to produce a gauge pressure of 7.00 atm?    kg He

  A hot-air balloon achieves its buoyant lift by heating the air in z h :6rfs,2nu/e1mwudd;,si iside the balloon, which makes it less dense thr e m2,is h sw:nd/;u1uzfi6,dan the air outside. Suppose the volume of a balloon is 1800 $m^3$ and the required lift is 2700 N (rough estimate of the weight of the equipment and passenger). Calculate the temperature of the air inside the balloon which will produce the required lift. Assume that the outside air temperature is 0 $^{\circ} $ C and that air is an ideal gas under these conditions. What factors limit the maximum altitude attainable by this method for a given load? (Neglect variables like wind.) $\approx$    $^{\circ} $ C(Round to the nearest integer)

  A tire is filled with air at tsko;ntla0 9e5id i;m s;+b,g 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 5z+*e wauruu5 $^{\circ} $ C and an absolute pressure of 2.45 atm are compressed to 48.8 L and at the same time the temperature is raised to 50.0°C, what will the new pressure be?    atm

  A helium-filled balloon escapes a child’s hand at sea r2abb12 4tpqa 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 molecj/b y b-o9,lawules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of wate/ i 8vygese2+ur are there in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of3 ( qatd/ch3f+ c+ynsc (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 volume6*f1u fv.8jkgr f1bkwss :: eh 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 that4i3awe 8rjzb 9 were also in the last breath Galileo took. [Hint: Assume the atmospjbar z4w98i e3here is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of an oxygen 6v64gd(y8p1bnh 8 z5) vxrbup9yq enhmolecule at ST6v4eq xn9p(6 5drzu)gybh8hb8v n1y pP?    $ \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 tempj0cz(t:b z2r upd*89 n1ezrak eraturetab1nc 8: dp z*9zrz0ju( kre2 of about 6000 K.    m/s

  By what factor will the rms speed of gas noq uwl 63w y)y2n8-nwmolecules increase if the temperature is increaso3qy nn )nw8u2wwyl6-ed 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 inso c;d ,ng1x4 iu02kix units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calculate the dg0ixo 2k,;sc4uix1n rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in vf k2 lc3lm7c :dbi rc;.r08gza 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 doubled while its volume is held consqp p jf 2n:n n7b:3/s*ygi3*kta4cyh btant, by what factor37i pjyf:s nt3 *nngc/hba pb:y2*qk4 does $v_{rms}$ change?   

Show that the rms speed of molecules in a d,:cqw34bldyscjp ia59 1 1 rrgas 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 r/f4-vxolqow 5w7 d 7kw7ri(naatio of their rms speeds is equal to the inverse ratio of the square roots o4fxwqad7n7 v-/o roi(7wwk l5f their molecular masses.

  What is the rms speed of nitrogen molecuab4 m07**ucudt(ey d5t+z lynles 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 7b:6o5dx yb4dra b5 than oxygen molecule at 0 $^{\circ} $ C    m/s
(b) determine how many times per second it would move back and forth across a 7.0-m-long room on the average, assuming it made very few collisions with other molecules.    round trips per sec

  What is the average distance between nitrol:;b:gz/nmh.jk0v w sx2 *r uhgen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular mass z,jqf; d6b*p,gje, vois 89 u in a liqf*;v j ,egpbdoz,6j,ving 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 can be wri1gy.a 2j- pji v)vrgf91n2psim 2l9setten 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 uranczirfw s h36; 525llshium, $^{235}$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 phases cawc4r 12to7d j3jnqw4t.pt*a wn $CO_2$ 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 th puy2dr*ckh,q hez*agxq9)3 )e temperature is (a) 90 )x g 3,qkr) equhcah*9zp*d2y$^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity is 50%y irbz*m) lt5/ on a day when the temp rm zti)5*l/byerature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water boils 1 xdx,e, dcz/: zdodk0at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in-rzz 4nx*iysj6y9 1iu the mountains is 0.72 atm, estimate the temperays9jn*- x z6ui1zry4iture at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day r80mt f3/cxagwhen the partial pressure of water is 530 Pa and t8f 0 c/3gxmrathe relative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day w8 z 48tci:sfoqhen the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure insidrgzu3uzpxnm 1ei m9 c*4v9uhz5-2n y4 e a pressure cooker if the water is boiling at a te3uu4u xp -*mz9ne4h 2zmz9yc15 rvnigmperature of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a roome;n;e wvt/rq m)jv6o3 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 pointdnl1fv ie 1),b 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 (wmt2d o- qzg+5u5gnm- see Table 13–4) to diffuse a dizotd2-+q numg55w- mgstance 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 insects to the ina;sij:/ xc-sy 7e-dez ,z;fisterior through tiny tubes called tracheae. An average trachea is about 2 mm long and hazsd,xcis- -ye;7i sa/:;z ejfs 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 bee :e60( edlqjzz 1zziz.n 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 4xu8mn 0n6 x5x1;8lge ykyxdcmeasure 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 calibc 2o4xx(u d60eh ay8gprated at normal room temperature. How much error will be made in a recipe calling for 300 mL of c8g (o4euxadhy 6 px2c0ool 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 many bi0mvv g(j/,18w 1ay8kwej moxalloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of the original gas remains jam,w8ox8 1mjg(0/ i1ev ywkvin the cylinder?   

  Estimate the number of air molecules in a lx f,zn1bsjbohcjf;scrn78y9 3/8d6room of length 6.5 m, width 3.1 m, and height 2.5 m/hsxc;jco1y9 flrb3 nz d6 nf8 78sjb,. Assume the temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter i7son7g s t*etbtey1 l,:7rg ti-sn7)t s 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 u3m;g8vow b o 6hs5n5lusing the best available vacuum techniques is about 5hl u 5w;obvo8 3gsnm6$10^{-12} N/m^2$ At such a pressure, how many molecules are there per $cm^3$ at 0$^{\circ} $C?    $\frac{molecules}{cm^3}$

  If a scuba diver fillsf ,s+i4+e4qx d2tyj jp his lungs to full capacity of 5.5 L when 10 m below the surface, to what volume would his lungs expand if he quickly ros2 xqie+t,+ jp fs4jd4ye to the surface? Is this advisable?    L

  A space vehicle returning from 96 ejwjh(. ofy3f3wu-ra rp 4qthe Moon enters Earth’s atmosphere at a speed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this speed corj39(w uef6wryfa-o q3.j4rhprespond 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 gaqk3af1a5 af:3yqlj n0s 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 pyr+(eyn78o ,gwiid; 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 surface of tu iwdfqa/1 -o+he Earth, estimate the total number of air/fw-odi u1q a+ molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed5 ;aiwz2ztu(t of nitrogen molecules contained 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 hos3fb1d mdjq9pb/ cw9, j0an2z;ht; tvcpital has gauge pressure = 2000 psi (13,800 kPa) anv ;ad9q2d/b9b ,thptjwz3 cf;j0c nm1d at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liquid mercurvr) +hav6 8 pg+apfv5xy 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 gasol iq3, taokv5 8w-eobo;ine at 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’s equa c uyy772)ylv)o p*v mrn4rsz-tor at 25$^{\circ} $C, but then was heated to 45$^{\circ} $C, how high above the Earth would the band be (assume equal everywhere)?    m

  A brass lid screws tightly onto a glass io:utgps,8 q .iv0uae7; )cr6vj ahq 7jar 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 standardtwrr 52a l *+pbj,or)b, 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 ful xmc:l 3/ahnt *w7k/gily charged, has a pressure 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 rls ud* w-d2ax:8xg:jh5w* 1m7olcak is $ 1.12\times10^{4 } m/s$ so a gas molecule travelling away from Earth near the outer boundary of the Earth’s atmosphere would, at this speed, be able to escape from the Earth’s gravitational field. At what temperature is the average speed of
(a) oxygen molecules,    $ \times10^{5 }$K
(b) helium atoms equal to $ 1.12\times10^{4 } m/s$    $ \times10^{4}$K
(c) Can you see why our atmosphere contains oxygen but not helium?

  A 1.0-kg trash-can lid is suspended against gravity by tennis balls thrown ,b2kdt+ evf8xb z*c-tvertically upward at it. How many tennkbvc zf+-,t*xe 8dbt2is 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 (spherical) bubble of9vcfn,e7p9 w3o t9cjpb 4rw/ k air from a depth oftpvowkc 9 wp ,3 4j/79erb9nfc 14.0 m in a lake. Assume the temperature is constant at 298 K, and the air behaves as a perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure in the air on the following two+jeq: h+vv p ml6hv96j days: hjv++pm6: 9 qe jhlv6v
(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 9w,fh lkww0mo/6pdhlm0* k8t STP, and when it is a solid deep in the Earth where the temperatmof 9wdt0w khklwp,l* mh0/68ure is 2000$^{\circ} $C and under 5000 atm of pressure. Assume the bulk modulus (90$\times 10^9N/m^2$) and the coefficient of volume expansion do not vary with temperature and are the same as at STP.    %  ----待选择----decreaseincrease 

(a) Use the ideal gas law to show that, folpo0 f-2dh6q x/n fp4rr an ideal gas at constant pressure, the coefqn 2lpdxh/0 ofr-4p6fficient 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 dehumitp f6z9g2ff x;dify their cellars to prevent rot and mildew. Ifpf2fxg96tf;z the cellar in a house (kept at 20$^{\circ} $C) has 95 $m^2$ of floor space and a ceiling height of 2.8 m, what is the mass of water that must be removed from it to drop the humidity from 95% to a more reasonable 30%?    kg