Which has more atoms: 1 kg of iron or 1 kg of alnj-x7jx3sq)0 r2o bv; vn ( +eshj3uleuminum? See the periodic table oroljs -( 3e3 r+s;eh0jxvnb x)u n2q7vj Appendix B.

Name several properties of materiay*2i; wsd,pdfp ajn0cct *z, +ls that could be exploited to make a thermometa pftd *j,c+*cz0i np,y;2dswer.

Which is larger, 1 C fegb8ao79l4,l+ kcf p$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B is not in thermal equ / 9yymhdu:a*zilibrium with system C, wy/dmha y:uz*9hat can you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to a stricfcky 8/s q16hp of iron. When heated, the strip will bend. Which metal will be on the outside ocych61s/q 8kf f the curve? [Hint: See Table 13–1.] Why?

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

The units for the coefficient of linear expansion zlcl(hhlq dgar( 332 ;vn-zr ;$\alpha$ 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 con1lnct;(gek xnj v)3: ntrol 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 n l): tkn3;gevn(jc 1xbe set at different temperatures.

Long steam pipes that are fixed at the ends oftsvh v;c0og rm5 c9j;e*en have a section in the shape of a U.h* vc0ec5srgvj; m ;9o Why?

A flat, uniform cylinder of le;p h ,robt1e)cad 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 placed2 3kof (:tftuz in a hot tub of water, the mercury initially descends a bit anfk zu3t:2(oft d then rises. Explain.

A glass container may break if one part of it is heated or cooled more rapid).whe+3k yylb ly t+lw)yeh .3y bkhan adjacent parts. Explain.

The principal virtue of Pyrex glass is that its coefficient of ls jrc/7.kp x8rinear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives ric/.jkpsrr 7x8se to the increased heat resistance of Pyrex.

Will a grandfather clock, accuratejzdhf ha-(((c 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 o)lr3 kicigx z: t2p:*3 vnvu(so badly the can will not stand up. ir nv*c3 kx ip23(:l)tuv:zog What has happened?

When a gas is rapidly compressu w ei4va4,omp) (wqi /v5,wyhed (say, by pushing down a piston), its temperature increases. When a gas expands against a piston, it c)/uwa4wiyw vq ep(v,4o5 ,imh ools. Explain these changes in temperature using the kinetic theory, in particular noting what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force on an aluminum sphere submerged in water ini2vgs2kwel5 6 crease or decrease if the temperature is increased from 20k52i esgvl 6w2 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law fol xv 95sf)): ufppy2fqllows from kinetic theory and the relation between average kinetic energy and the abpfvlp:y2sxqu 5) )9ffsolute temperature.

Explain in words how Gay-Lu, p:bn2udbop dne39 ;cssac’s law follows from kinetic theory.

As you go higher in the Eahf.9p:lf4 (hwxmr1tt rth’s atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum sp d*ut6cvwh m ) cg91y,wt0o gw/ybr30zeed an object must have to leave the Earth and never return. The wyrywwvc,b gug d/0) 30mt t69z*o1 hcescape 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 wate.pb wz-i*u -7gz:hkg br at room temperature. What can you infer aboutgz g.7z p-h:b*kbui-w the molecular properties of one relative to the other?

Explain why a hot humid day is far more uncomfortable than a hot dtfb98z0h,l ks+ f3yinakj 6n4(w.n ivry day at the same t0 h4zayn3k+v9j.,ilf8sfwkb nt6 (niemperature.

Is it possible to bo ks3c2gq zt:i-il water at room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperrl (n/2ceye6u;tx ai2ature is the same but the humidity is different. Which is more dense, the dry air ouyaleei/62 t ;rcnx2( r the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap of1wk::f 4kb dqs an overheated automobile enginwskqf: kd :1b4e.

Why does exhaled air appear as a little white cloud in the winter (Fig. 13–uegv7km q014q 7yuw8(vx+a tw28)?

  How many atoms are there in a 3.4-grami/ s3 3ynee3eq 1il,it copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram la:4 tdu iyhsv5 b/ kwb)6baz5*tdm.;gold ring compare to the number in a silab5.mhb6itst kawduvld by)/ z4 ;:* 5ver ring of the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. Whb w+ 9 9tko76t)oybidhat is this on the Celsius scale?9kd6 oibowbth)9+t7 y   $^{\circ} $ C
(b) The temperature of the filament in a lightbulb is about 1800 $^{\circ} $ C. What is this on the Fahrenheit scale?    $^{\circ} $ F

  Among the highest and lowest temperatures recorded arg qa:;zza( 8 cp0d5fehe 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 oucmv;p b09w0wp3b3y . pto 57y edbj-thermometer, the alcohol column has length 11.82 cm at 0. u wdyw3j tbc3pppv-0m70beo 9y5 ob;.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 mc k8-zr; k+f9er/ njn-axly 1 i3 :xn5fsbiba7 long (20 $^{\circ} $ C). How wide should the expansion cracks between the slabs be (at 20 $^{\circ} $ C) to prevent buckling if the range of temperature is -30 $^{\circ} $ C to +50 $^{\circ} $ C?    m

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

  The Eiffel Tower (Fig. 13–29) is built of wrought iron approximately 300 m tgt)5fh7)nj ew u 4z5uiall. Estimate how much its height changes between July (average temperature of 25°whu )ueijz f55gn7) t4C) 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 larger than the rive1g2s2ab /mh ast hole are often used and the rivet is cooled (usually in dry ice) before it is placed in the hole. A stehma/s2g b21asel 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 aii9kgr4bd*ghf-f gvq2 6s n70 t 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 dw2dnlae5n19w6 4uki6 -iqsj +j6etj+ (ry js ciameter. What will be its change in volume if it is heated from 306lc(y- 6utww9eneq1j n4sjjaks6 2 r + jid5+i $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350.0 mL of wat3kz w s 5m:uzd8e3+(ag)p xzater 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 -71au iv 1xjdj55.50 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 to be placed in a rin ud4x,hgdb;:sg 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, nar+otb r0w4 ,y 42lcvuqsd: 1oasrow vessel so it can expand in essentially one direction only, show that the effective coefficient of linear expansion is approximately equal to the coefficient of volume expansiosd142,v br uoy:c 0lat+4qwson $\beta$.

(a) Show that the change in the sarvui/d6 z d+q3 uf98density $\rho$ 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 coefficijx 1af2k9c; uwent of linear expan9 jk xcuw;f1a2sion $\alpha$ 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, -9.cbf su4gbe $\beta$ = 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 per5 wdlc).i 1 rr*u(xkaifect time at 17ixu5 r* ).(dawcr1ikl $^{\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 di9advetn24c n/ ameter of 0.140 mm. The bulb en a9cn/4dv 2thas a volume 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 ikrdt:9o2fkl r; /i 5rctr o)k/ts axle on frictionless bearings with anguo dtt/rki )ok;flr 9rc:5 2kr/lar 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 de2g6g skouwlc s3,0w(c sired length when at 15°C. How much stress is required to keep it at this length if the temuco 30ks(6 lc2g,wgwsperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of crsx ge 4wc6z+o,oss-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 lsfkbvm3x 7n+cx)-f :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 temperatures8m)g, 6qpkifcc(4i as on the Kelvin scale:
(a) 86$^{\circ} $ C,    K
(b) 78$^{\circ} $F,    K
(c) -100$^{\circ} $C    K
(d) 5500°C,    K
(e) -459$^{\circ} $F    K

  Absolute zero is what temperature on the Fahrenheit scale? k*:1nvkg-xk-yie5 yv    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Szv 3wso/h6 7dqg2sg( bun 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 atmospheric pressure and ae*( ok)gv9muuy/2 (kvlszp ,q temperature of abouzu*symgq2/uv ,l v pe)(o 9kk(t 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 thewa5ny6bu1mie0f0fb /fa, 5 vb ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 mb-*bur96 aoi 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 1gref (vpgn 7 rh0b6v838.5 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 w;gpws ** (mar ihgj;+*w9h, :veug eois 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 insirevwj f-0a (c5de a 35.0-L container holding 105.0 kg of argon gas at 385refwa j c05(v- K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg pi0)ijzup 7kqt9ap6ya03 h ;kof $O_2$ 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 inside the balyuq uqt + nmu5h,*kx/ m7knwyb+i2;r*loon, which makes it less dense than the air ; k*unu 2txyy+ r,b /w*5h +qmiukqn7moutside. 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 15z3z8 fyec r(s5 $^{\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 az 1 v/ui9bxnbv-fq:i)t 18.0 $^{\circ} $ C and an absolute pressure of 2.45 atm are compressed to 48.8 L and at the same time the temperature is raised to 50.0°C, what will the new pressure be?    atm

  A helium-filled balloon escapes a child’s hand at sea level and by*),k6at; 8phwda6 e+nmn po 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 molejqzq :t6lkxm t., 9ub:cules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L/)b/i tleds3m98 fs bh? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) moles,1 jsdnd*( qcjh25qyk6f4p9we    $ \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 5sw ra;j2xxh86gs2r 8/c uvfa,.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 that whur2 2j qswd;7ere also in the last breath Galileo took. [Hint: Assume the atmosphere is about 10 km high and of constant7u q;dsr2 2hwj density.]   $\frac{molecules}{breath}$

  (a) What is the averagv2 v bfj6d51nd7xyv 6 zysb,i6e translational kinetic energy of an oxygen molecule at STPi6sdvz b7f 65jnbd,yyxvv12 6?    $ \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 atik g3/t9jat p2oms near the surface of the Sun at a temperattj/3 9 2kgpatiure of about 6000 K.    m/s

  By what factor will the rms speed of gas molecules increase if the tempernhay o/3 mbmh94x0an yt*n1* kature is increas/ tk 1 9a0hmhbmnoya**n3xyn4 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, giveng/,.r(jtl2ypuv(p 9dz dp3o z in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8 zy2((vuj dp olg,r/p9t dp3z.. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at 20.0 mo- ;vo0, di sgm9wseyq+,rt8$^{\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 constan,(g n8 ch5banw(-pr 0dat6vqf.uv6bl t, by what factorcntr,q anwu(68 5fdlvbhvagpb60.-( does $v_{rms}$ change?   

Show that the rms speed of moleoy0pwj8 iafvfp ;+i;+cules in 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 tem t+z o (nkru84k*l)pndperature, the ratio of their rms speeds is equal to the inverse ratio of on* t dur4k kln)z(p8+the square roots of their molecular masses.

  What is the rms speed of nitrogen molecules fx( o;;a:tfwp 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 moleculecl hus47l q8yd 8.arhka5td a(g68fk( 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 betwee woav+,.fdu:xpcia )qe*,e6 tn nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular mass is 89 u in aeir4 m-odfq .) living cell ati.erqm)-d o4f 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 bew ur(r-kw7 j aj(y(mox,v d8e3 mv5d,c 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 uraniu 88-i jsd6zv9ottp5 e 87idzsmm, $^{235}$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 ry7wd rmk :e+ fs 8lbqc4ks)17(lzs7pphases 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 im -9mslm .pjhtt3* 6rfus+t0is 0.01 atm and the temperature is (a) 90 r0-.9*stimm3hm tps f6j utl+$^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity is 50% on a da )tfdv0dpd(q*y when the temperature is 25 t) v*dqp(f0 dd$^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pres1x dvfo.df- y7sure at a place where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place 0pse7r7 p/*8 l cgkdbkin the mountains is 0.72 atm, estimate the temperature at which watbk/gd ce8 s*0pl77pk rer boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of water is 530 Pkqxph+8ji7 nld8k.nb2ynm d) 24g* pea and xkl *n mbj)h+ d.ni8g4pkpe7n d y282qthe relative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the temw0io ys.+hw r*k( oavo8kb v9)perature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate presst,jbjaj0 (;wx5qwq ux23 1kbyure inside a pressure cooker if the water is boiling at a t a5bj0wx(qu q 2,1yjxk wb;j3temperature of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a rooog + dl0cn3l3 du:dn+fm 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 5 bu(r+ck*eo, n$^{\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 Tabl wv0v 52g04ahzxu; a.qsja0ck e 13–4) to diffuse a distance ;ka0 4aq5j20au vxg0 zsw c.hvof 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 thh4;*nawpt2wt0h lfhkdw(k+ q /a(pz ) e interior through tiny tubes calle4haqtkl p0dhz;n)t2 hkp +(w*wfw( a/ d tracheae. An average trachea is 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 tape measure has been calibrat11m)vgb oh/ 4 +w;ugz ir(p cxhu62scded 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 measurfcvgx s2b6(v 4j35aw oe 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 .l eeh*z6vz x3normal room temperature. How much error will be made in a re .zv3h6lxe*z ecipe calling for 300 mL of cool water, if the water and the cup are hot, at 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in a helium gasr -h jh.,-ic(chez:lky o,1p( qp*ety cylinder is initially 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of the original gas remains in the cylinde i tq,pjcc:1ylhe *z,oepkrh-. h-(y( r?   

  Estimate the number of air molec eb2i4*huslrh- m:0h( 0dtzbuules in a room of length 6.5 m, width 3.1 m, and height 2-ubzu(:s2mh db0tie r4 h *l0h.5 m. Assume the temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of mat vcy)4(-w8m bqh dg/ecter 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 available vacuum tech,;btrolu5 ih kt;z54y niques is about tk5i5u ,4rhozy t;;bl$10^{-12} N/m^2$ 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 whr6v1 s7p q2aowm( y)mben 10 m below the surface, to what volume would his lungs expand if he quickly rose t27 w6pr)bmq1sa vy (omo the surface? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmosphere aqt ,;lyrn9aoaj+ obz2 :1zvf3t a speed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this speed correspond to what temperature? (Because of this high temperature, the nose of a space vehicl o91 :n,yjavl2tq+3 zrabo fz;e 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 increaslw;d n (7pdg2oen e;pl.f6 dl(ed 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 of g u4,:g0lv nhx770m$^2$ (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 atmkjq0hrgh0f c1 1f*)dl9ld / raospheric pressure at the surface of the Earth, estimate the total number of air molecules in the E0r)hh1 /fjdqrk1dc*la f9gl 0arth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecul/k3eowikcl7m* (ok -pes 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 hospital has gauge iz uz6gsy-v6ntao/ *5pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if theg* uiz/oy6s5v6a- ntz flow rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liquid mercury at(2m. -ddalgf: shc y0q 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 v/j2fikffg i02.t ef( 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 sno 0+81ofjg/sq vavhk,ba2r f0ugly 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 t(r s /.zblfzz+ightly 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, adopted in the1n ve9 esp))fd x5x-jm 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 fu eh 0d)5dl0x2zuyyh t0lly 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 irp0kv9;u na tjmu ss3-l)4o74z.sdcEarth 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 throo ai3.: +lo(n ope6rflwn vertically upwardlo r a(e36n.f+o o:lpi at it. How many tennis balls per second must rebound from the lid elastically, assuming they have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter (spherical) bubble of air from3p3 rfwxku5vo 4 bm9 ,2 ybapluk4lf4+ 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 is the bubble when it reaches the su3aox4 w l2+p44 3 9bf5,uumyf pvlkkbrrface?    cm

  Calculate the total water vapxc(lj-u 0+ncvq /xs2w or pressure in the air on the following two days: 0(2luv-w+ /qc csnx xj
(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 ofro9hc7l;(w; zlnv+a: ll /va v iron at STP, and when it is a solid deep in the Earth where the tempva/aw( v7v+hz l;l9cnr; l: loerature 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 thq)9l5bkv kcf 8)kw7b iat, for an ideal gas at constant pressure, the coefficient of volume eqlb) bkwk cv8f7i95k) xpansion 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, peo6byb.d(umkho3h 7yd1/x (46 ac ehzqkple constantly dehumidify their cellars to prevent rot and mildew. If the cellar in a house (kept d ea(6bk( 4ocd7.uyzh q3xbym h16kh/ 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