Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodic o2x5iirh 08 gktable or Appendi52r x8khgoi0ix B.

Name several properties of materials that could be exploited to make a thermome9fj cq.dme-: ote f-.cm:e9qj odr.

Which is larger, 1 C-cwxj57wpr (h $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system yr- g67x8ph1u*uvqby-p v) da B, but B is not in thermal equilibrium with system C, what can you say about the temvu1qp7*ap8)b- -ug vh6dxryyperatures of A, B, and C?

A flat bimetallic strip consists of aluminum ri xl38y 9jajzy 9;siy*kveted to a strip of iron. When heated, the strip will bend. zjiy8* lkyaj9y s;x3 9Which 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 coefficrk/(+3 *o zu+apjlrufient 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 use4 t ul xxa(knbiov-5,8d to control a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch is a glass vessel containing liquid mercury that conducts electricity when it can flow to touch both contact wires. Explain how this device controls the furnace and how it can be set 4,na lb(8ukx5v- xoit at different temperatures.

Long steam pipes that are fixed at the ends often have a section ina us,lb0 gw.j i2:az7o the shape of a Ub gjw0.z l2u7 i:,asoa. Why?

A flat, uniform cylinder of lead f;7 4 +0aulfgoea2luv yloats 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 thermompf xadfk g;t5:;4q1e6jahxw8 eter is first placed in a hot tub of water, the mercury initially descends a bit ank:pgq4;d6xafj; t1 hx5f8 waed then rises. Explain.

A glass container may break if one part of it is hh),mhgzo 1z- sl+zl 8reated or cooled more rapidly thanm8lzs- zho h)rg1, l+z adjacent parts. Explain.

The principal virtue of Pyrex glassg zktgp/2 4s.a is that its coefficient of linear expansion is much smalgkg2t/4sz a.p ler than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurate at 20 v 0b7,qpxugu3 $^{\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; p 1c4mbtpoj: and top to bulge so badly the can will not stand up. What4 :j;otpbmp1 c has happened?

When a gas is rapidly com6h8 50*ijx)ga bxl0x9tusv pmucl4+y8whc o :pressed (say, by pushing down a piston), its temperature increases. When a gas epu0ywlm0x5j ta*:co946ixvx gs h h 8luc)8+bxpands against a piston, it cools. Explain these changes in temperature using the kinetic theory, in particular noting what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force on an aluminum sphere submerged in watvw) 5dol;0x lder increase or decrease if the temperature i d )l0owvl;xd5s increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kk kf*mx0) t7j 2v4cbekinetic theory and the relation between average kinetic energy and the absojv)e*4 fxtkk b 0cmk72lute temperature.

Explain in words how Gay-Lussac’s la8fdrf wboc-(8w follows from kinetic theory.

As you go higher in the Earth’s atmosphere, the r*vv/ b-n)1 -yncglalf;alst 4atio 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)hfr-r 6z8ggg 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 practi8)- fhrggzgr6cally no atmosphere.

Alcohol evaporates more quickly than water at room tempe/pfg0lalyj /b84 ;svsd(s( n g5s)lulrature. What can you infer about the molecular properties of one relati/;ss(l4lls fsuv8 5ybgg 0/ (p dnj)alve to the other?

Explain why a hot humid day )c9(28g obztho tkcj1u z2og,is far more uncomfortable than a hot dry day at the same czo(91 zoho 2ktbu8)jg,tgc 2temperature.

Is it possible to boid ,re 8:tvdesv-o8uuh,xn 9o)l water at room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the humidm/md hevuy1c l.5 m8i1ity is different. Which is more dense, the dry air or the hl hcu m.5myd/8me i1v1umid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap of an overheatedrbj 3cj,2ry.dcx55 mi automobile eb,ij c.3yd xr2mjc5r 5ngine.

Why does exhaled air appear as a little white cloud inlf :tz6n7 gf(n the winter (Fig. 13–28)?

  How many atoms are there in aus)* d:dv8(lvlr u ehsf6tb69 3.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare to the nuyh/h/f we/zw2mber in a silver ring of the same mass? w2fy/ h/eh/zw$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to7*fx;;mqo wvq be 68°F. What is this on the Celsius scale?woq x f;;7vm*q   $^{\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 recordg;fhlk1 hqeogd /o,jr3 48wc-a3:l8kfqv 2v ged 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 colub+ lsmf(z 4d4:;tjc ewmn has length 11.82 cm at 0.l4 zs m; fdb(e+jctw4:0 $^{\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 slabs 12 m long (20+ pwj3o5es y7u $^{\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 builg sgknobrb3*- 9 6xcr(t of wrought iron approximately 300 m tall. Estimate how much its height changes between July (averb gno(bx-sr c6rgk *93age temperature of 25°C) and January (average temperature of 2 $^{\circ} $ C). Ignore the angles of the iron beams, and treat the tower as a vertical beam.    m

  To make a secure fit, rivets that are ika16s5u tx(3:q .uip bjwl: zlarger than the rivet hole are often used and the rivet is cooled (usually in dry ice) before it is placed in thexsiu3 :q (l6az.up:ikwbj15 t 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 ri wkbus0k):3p5:bsm$^{\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 0bgm .yy1spu4r9cm0b change in volume if it is hbmp9rs ycg0u m.b0 y41eated from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is yab(u *7f.ak r.i53vlttii 3b filled to the brim with 350.0 mL of water at 100.0$^{\circ} $ C. If the temperature decreased to 20.0 $^{\circ} $ C, how much water could be added to the glass?    mL

  It is observed that 55n;9ugm gr2k1u /(b+cynw vxy7y fs9h. .50 mL of water at 20 $^{\circ} $ C completely fills a container to the brim. When the container and the water are heated to 60 $^{\circ} $ C, 0.35 g of water is lost. (a) What is the coefficient of volume expansion of the container?    $ \times10^{-5 }$ /$C^0$(b) What is the most likely material of the container? The density of water at 60°C is 0.98324g/ml.

  (a) A brass plug is tojg:d+/fp:vq . 7 ahgkn be placed in a ring made of iron. At 20 $^{\circ} $ C, the diameter of the plug is 8.753 cm and that of the inside of the ring is 8.743 cm. They must both be brought to what common temperature in order to fit?    $^{\circ} $ C
(b) What if the plug were iron and the ring brass?    $^{\circ} $ C

If a fluid is contained in a long, narrow vessel so it can expand in essentia)pu+ty8 ;tbbully one direction only, show that the effective coefficient of linear expansion is approximately equal to the y)pbt uu b+;t8coefficient of volume expansion $\beta$.

(a) Show that the change k:sjl ds/;tm/,a au4get2f9a 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 e9 vn mr9)8upncoefficient of linear expansion ) 9rmvn9nupe8$\alpha$ 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 isot2 dc-g ,;o yuc ypp-2hc9)kv gc/m;wfkropic solid, $\beta$ = 3$\alpha$ if the amount of expansion is small. $\beta$ and $\alpha$ are the coefficients of volume and linear expansion, respectively. [Hint: Consider a cubical solid, and neglect very small quantities. See also Problem 18 and Fig. 13–30.]

  The pendulum in a grandfather clock is made of brass and keeps perfy7g1wsyqtv n dl728j 5ect time at 17 gql7w5y1n28s td jy7v$^{\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 l)jy1 j xytoo1pdd-5aw*h5 (phas an inside diameter of 0.140 mm. The bulb has a vap*t1doy1 x -w j55 (lyj)dopholume 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 rad y-k 4uqpy)ui ;0/sj z.z aiv-d*svl0xius 0.41 m is rotating about its axle on f0u isk*avz.xyqvu 4zj l)sdy-/0;ip-rictionless bearings with angular velocity $\omega$ = 32.8 rad/s If its temperature is now raised from 20.0 $^{\circ} $ C to 75.0 $^{\circ} $ C, what is the fractional change in $\omega$?   

  An aluminum bar has the desired length when at 15°C. How much s4mr6v0 3t mhvhtress is required to keep it at this length if the tehv m vtr6m0h43mperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cros c5zar.-cn: r)+o sscqs-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.)oawz o:s z(rmd:5p).hcq4gp 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 + ,9i juil )w7*fxhhxrKelvin 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 t .m5 iqz)3u/b8urwuyohe Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and 3op.tyuywws) 5r5* ddi2or(7/p k dj5 zs3deaSun 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 ens2b- k r *kvnoy,p,x*ugine, air at atmospheric pressure and a temperature ofvp, kbn,xs-yu* ro*k2 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 using the ideal gas j yi*)p8y,dmmlaw.    kg/$m^3$

  A storage tank conta s0 kd.x(n jdg3z4x*vwins 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. ee6zv4 b48)j:tbph4fi rm wx: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 heliuu7c1oih8++r:t kq0fy 3 l hfezm 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 container holding 105.0 kg of 4s81dhyzi 14j+k: xc 8rr dsmyargon gas at 385 K?cxr h 4s:rmz d18js+4yyi8d1k   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg +1 v 4f ln9pvn2qs.gwmof $O_2$ 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 heatinm7r ,lp2 ;ridbg the air inside the balloon, which makes it rp7ld,bmr; 2i less dense than the air outside. Suppose the volume of a balloon is 1800 $m^3$ and the required lift is 2700 N (rough estimate of the weight of the equipment and passenger). Calculate the temperature of the air inside the balloon which will produce the required lift. Assume that the outside air temperature is 0 $^{\circ} $ C and that air is an ideal gas under these conditions. What factors limit the maximum altitude attainable by this method for a given load? (Neglect variables like wind.) $\approx$    $^{\circ} $ C(Round to the nearest integer)

  A tire is filled with a1on8/ob hk9wp8p :lts0ct6kw ir 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 atp9kp rikh57,b, j9n:e:zug; 2jn dx tc 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 escape bnk72y3qw; lf6,wqqq)up o3xs 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 of molecules/ i)paatopg c/ pn:4-x / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of wa-xe+eozscmu739m )bzwyq) j/ ter are there in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of v 1k.ekm3: tf.c o2zgm(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 volumix/ryfo(g8-q 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 brw6xf+y)w,sv,duy 2 zveath you inhale that were also in the last breath Galileo took. [Hint: Assume the atmosphere is about 10 km y, vu) zsxdfw,y2vw+6 high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translationalid5a3id6hm s. kinetic energy of an oxygen molecule at STP 6 sd5dm.3aiih?    $ \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 tempzv8- 31c;laauk7me f ferature of about 603l78 ff;ev 1uzmaac- k00 K.    m/s

  By what factor will the rms speed of gas molecules inc;4rn,sl6 tae frease if the temperature is increased from 0 e af,lnrt4s6; $^{\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 units of km/s: 6, 2, 4,4(joj,9iydy( jbrb7fv g7 a+nsuun 4 aurh7 5. 6, 0, 4, 1, 8,by g4,jua(v7yuo.+sn5(j4 jn7u 7brdai 9hfr 5, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of moleculz:w )1wpfn* zb 9q18m4bvz9qqj1tufiq 4ou;d es 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 dozeuc4h8i17 s x5 usvn h/9iu 6v),dqukubled while its volume is held constant, by what factor does kixh huiuv46)s7e,5vs/ u8c1udz 9 qn $v_{rms}$ change?   

Show that the rms speed of molecules inge;cw2g5 c. bbz)gzx3 a gas 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, t(ep4fujo0d aa*fk2-vhe ratio of their rms speeds is equal to the inve e poua -vffkjd4(2a0*rse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen mo te7(b6z kxhcmly.-4 kc,*wtzlecules 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 molecule at 0 :reac:9e 0/ngu n y/fw$^{\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 betwl tgppnlg6m y(v(-7bql 2jw.1een nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed 2po. l0ef svrr ,*vxuayp84 xjm6;g0mof an amino acid whose molecular mass is 89 u in a livingx; , 0 r68yj42p0ov.vfa l re*mgmsxup 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 hen k*pw(5i-ay4o) gvur+*dt of a gas can be written P = $\frac(1)(3)\rho v^2$ where $\rho$ is the density of the gas and v is the rms speed of the molecules.

  The two isotopes of uraniuel .* r0q*oai m1up vf:d k/7/8whaxjhm, $^{235}$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 phaseihkyzi)g7 pfq wd(3+ 6s 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 temperaturexa6xjvp-*6o, sp ksh0 is (a) p-xakvhp6sx *sj60o, 90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity is 50% on a 4utnu6p4:l 2whk: zt lday when the temperature iw :4u6ul h4ttnlkz2: ps 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at at jct/g ypf-/: place where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mounb7. (nu4bpf /7jpgitobquy . 6tains is 0.72 atm, estimate the temperature at y(qnu6fjt..ppb7g4u/i ob7 b which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of water z5))qiv)u on ml.3bjdis 530 Pa and the relative humidity is ldb)q.3uo )j)m 5nzvi40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the temperature is 25 cbz/rfzjk192$^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cookxkjty .; .dsso+xt/e 4er if the water is boiling at a temperat+e;/ xytsdjt4o ..ksxure of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room of volume 68z drde*k rt)f35b; z2pgw q-:n0$m^3$ at 25 $^{\circ} $ C is 80%, what mass of water can still evaporate from an open pan?    kg

  Air that is at its dew poin/e: v o+v3xitexnh 10+x1wlaht 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 dky 8+/)wmgzh6yj frd: iffuse a distanc 6):h+kfmyrgwy dj8z/e 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 interior t9:x8ghnph m7+cahx v2 hrough tiny tubes called tracheae. An average trachea igahn7mvx9h 8:c+p hx2s about 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 tapeaq.1v9cfj4cr**ph q t:h zf d6 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 precise steel tape measure has been calibqrj/c )nf g5(jrated at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A Pyrex measuring cup was calibrated at normal room temperature. How much error ;g9/uwll-y e vw ; dgf;inzx+(will be made in a recipe calling for 300 mL of cool water, if the water and the cup are hot, at e d(wxwi lg ; ;lnv9-fg+;/uzy80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in a heli r(ukahv6f*r gsaqh5il; 0,ds:z;*ud um gas cylinder is initially 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5ur6slr 0*gq;;d ah: uzavid,f 5hsk(* 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, widthopw04;wbj h+ u 3.1 m, and height 2.5 m. Assume the tempe4u+ wohbp ;0wjrature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the densitq a6ztyvg 2ybnr; cgy u2 )z*kvw,5g2gtw6 s11y of 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 best availa8 jp (rkf7 5fi1iom) jcy6b*esble vacuum techniques is about(cm*1)j8bf5jo 7kp 6ir sifey $10^{-12} N/m^2$ 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 10 m berpf;c 0pfp2ne z5l97clow the surface, to what volume would his lungs expand if he quickly rose to the surfa r7cnl9 2pz5p0 efpc;fce? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmosphere ycun2vwv e4i :.,rgu7at a speed of about 40,000 km/h Molecules (assume nitro,wn 72 v:iy.ucgru 4vegen) 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 increase0-ixne7s8 ) yoz+ rsbxd 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 ocoqb7c )k c)j *qllw5o 3u3u,ff 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 a5ng :hsz: kan5rw-ms: 93v azxtmospheric pressure at the surface of the Earth, estimatezks :wvn3r-n:5 aa5xm9 h:z sg the total number of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitr)3scbv8flbv t1 m7gs* ogen 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 virww+m4. 0hr m jb2r0of oxygen used in a hospital has gauge pressure = 2000 psi (13,800 kPa) and rvwr 0mirj+b4w2m.0 h 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 x+kh4pnj ) kv(in 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 gasol2-(nelbpk;c y 2cr po,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 snuglxbg 9jgb0ruk91sb8j7qe f 1d ;y around the Earth’s equator at 25$^{\circ} $C, but then was heated to 45$^{\circ} $C, how high above the Earth would the band be (assume equal everywhere)?    m

  A brass lid screws tightlsj lgck-.)5e zy onto 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, adoptedjplpb(5ac c x)k1,bx 5 in the 18$^{th}$ century, was a platinum bar with two very fine marks separated by what was defined to be exactly 1 m. If this standard bar was to be accurate to within $\pm1.0 \mu m$ how carefully would the trustees have needed to control the temperature? The coefficient of linear expansion for platinum is $ 9\times10^{ -6}C/^{-1}$. $\pm$ =    C$^{\circ} $

  A scuba tank, when fully charged, has a pressure of 195 atm qfyg -lk e)w+)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 is9,8 l2i:,t1 auhcv8dyc qpgws $ 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 throwntmis;hvh+t /,q 8+lmv vertically upward at , +;ti+ hmq lsm/th8vvit. 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 (sph,fed7e0c/ ms)d-ttc herical) bubble of air from a depth of efsce, t d)m0 7tdc-/h14.0 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 g2ji fn1 a1y1ibz..ikb; ;uiw two days: ;y1 w ii1af ;2i.bjz1uignb.k
(a) a hot summer day, with the temperature 30$^{\circ} $C and the relative humidity at 40%;    Pa
(b) a cold winter day, with the temperature 5$^{\circ} $C and the relative humidity at 80%.    Pa

  A sauna has 7$m^3$ of air volume, and the temperature is 90$^{\circ} $C. The air is perfectly dry. How much water (in kg) should be evaporated if we want to increase the relative humidity from 0% to 10%? (See Table 13–3.)    kg

  Estimate the percent difference in the density of iron at STP, and when ito*kl x4t(m2nb is a solid deepx2t blmk*(4on in the Earth where the temperature is 2000$^{\circ} $C and under 5000 atm of pressure. Assume the bulk modulus (90$\times 10^9N/m^2$) and the coefficient of volume expansion do not vary with temperature and are the same as at STP.    %  ----待选择----decreaseincrease 

(a) Use the ideal gas law to show that, for an ideal gas at constant pressure, 5 ) 5ltjx6 vg3 k.maibci/nk,hthe coefkmxk,hil). i/tbng5563 vjca ficient 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 2xen ;lm nkmn*c9c*a/ dehumidify their cellars to prevent rot and mildew. Ifck;mmen nl 2nc*x9/*a 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