Which has more atoms: 1 kg of iron or 1 kg 80qf9oz5vg fjaqgt-xi88 uc ji7 77moof aluminum? See the periodic table or Appendix B.f9a gq i7 t87zvq o8jgf0m5 c7ijxu-8o

Name several properties of materials that could be eq esr2/zm4z.qp 8(gii xploited to make a thermomet qpg4 /8.iezzm(2riqs er.

Which is larger, 1 C up(fit 6*ott0 $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B is not in therma 8wibth .+,e 5 t8-a-wdslwvtdl equilibrium with system C, what can you say about the tempert +d-8. stilh-bw5wvtdw8 ea ,atures of A, B, and C?

A flat bimetallic strkm) i iswm.xm(7dj 72qip consists of aluminum riveted to a strip of iron. When heated, the strip will bend. Which metal will be on the outside of thm7) s 7dm(ixmkiwjq.2e 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 i *jrmw7ujb,pp0k8 -t 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 simpleo0f a lcq(54,y-k wecnao60/nmx,yhg 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 electric switch is a glass vessel containing liquid mercury that conducts electricity when it can flow to touch both contact wires. Explain how this devi lq -kc4( oy/0,nwa5y o0fnx,h6gcmaece controls the furnace and how it can be set at different temperatures.

Long steam pipes that are fia+36r9mk bog vxed at the ends often have a section in the shape of a U. Whyr6mvao+ 3b9 kg?

A flat, uniform cylinder u39s:x4p sqid0nbsk;ae , *tmof 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 jfu ;8;rro*9) ihpm-ht 1yk guis first placed in a hot tub of water, the mercury initially descends a bit and then rises. E *jk)rhofhi;y tu 19;m8- uprgxplain.

A glass container may bren mo 8sk;n1n+xvvd;e1ak if one part of it is heated or cooled more rapidly than xd;e m1kv;o+1s nnnv 8adjacent parts. Explain.

The principal virtue of Pyrex glass is that its coefficient ofkf d*pfko4 7mra1/sq) linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resikdk q)p1/ o*ms47far fstance of Pyrex.

Will a grandfather clock, accurate 0owwg; ba(*mm z21sg6e2e czd 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 ekl 7npca;4n b2i53zd bottom and top to bulge so badly the can will not stand up. What has h le;az4 2 7c3ndkpni5bappened?

When a gas is rapidly compressed (say, by pushi3t*2+i gbo atx09k mf fg7jhq* 0rdc7dng down a piston), its temperature increases. When a gas expands against a piston, it cools. Explain these hq+ o r 9*3i 7bfgd*jtgkx m2d07fc0tachanges 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 submerig8 c 4mlg8gb*ged in water increase or decrease if the temperature is increase lc8m 4g8gi*gbd from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theory an 26a*6pdr-w4; aswuda2t upsxd the relation between average kinetic energy ant xdda -s2 u6u6s ;24prwawap*d the absolute temperature.

Explain in words how Gay-Lussac’s law follows from kinetic the gonife skl9qn+:y. 68ory.

As you go higher in the Earth’s atmosphere, the ratio of 1.u brg- n7xgr lz.( su1:ixyj$N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for th ,lh:cpwd)0r1xkg yt2p:ngn (e Earth refers to the minimum speed an object must have to leave the Earth and never return. The escape velocity for the Moon is about one-fifth what it i )n cp1rk(ty :w:pxn,dg2g0 hls for the Earth due to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at room temperature. Whwy5r6n 2prss5 xw)yt7 at can you infer about the molecular properties of one rsr5ytx2w6 s7 rp 5y)nwelative to the other?

Explain why a hot humid day is far more unc6xsw/3h gzsx5 omfortable than a hot dry day at the same temperash xgs6zx w53/ture.

Is it possible to boi0s(vt-hz:e v;h*ukbo (43nblp8 eqrc t hu11 il water at room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperatur4zzqr5gnq r1+e is the same but the humidity is different. Which is more dense, th5 zq+ng14rrqz e dry air or the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap of an overheated automobileo kw654iw92o w 9z iazxxf-j;s engiwzs9;owa4iwx 5k- 2i 69z fjoxne.

Why does exhaled air appear as a littl ujbqrk j76 hjj-)5cmu/sc l;-e white cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram copper penny?4 r/zz) c ;*ppfc1byvi   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gra o* d71tskwd)lm gold ring compare to the number in a silver ringlw)k1d so d7t* of the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this y5 ain,w+yes *59qtm pon the Celsius scale?*im yaqen5,9y 5swp+t   $^{\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 n wllnyk(7)p:n dop0pbr0: o- lowest temperatures recorded are 136 $^{\circ} $F in the Libyan desert and -129 $^{\circ} $F in Antarctica. What are these temperatures on the Celsius scale?high =    $^{\circ} $ C
low =    $^{\circ} $ C

  (a) 15 $^{\circ} $ below zero on the Celsius scale is what Fahrenheit temperature?    $^{\circ} $ F
(b) 15 $^{\circ} $ below zero on the Fahrenheit scale is what Celsius temperature?   $^{\circ} $ C

  In an alcohol-in-glass thermometer, the alcohol column has length 11.82 cm at (v0r+u vey98,f ghzgs0.v,(z sfu09 8+grvheyg0 $^{\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 isb.jg2y5*zbl y built of slabs 12 m long (20 $^{\circ} $ C). How wide should the expansion cracks between the slabs be (at 20 $^{\circ} $ C) to prevent buckling if the range of temperature is -30 $^{\circ} $ C to +50 $^{\circ} $ C?    m

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

  The Eiffel Tower (Fig. 13–29) is built of wrougho d3c,mejm+( /ns g;e0r4 dwwbt iron approximately 300 m tall. Est+r emo ;nsdgwdb4c0wm,j/( e3 imate how much its height changes between July (average temperature of 25°C) and January (average temperature of 2 $^{\circ} $ C). Ignore the angles of the iron beams, and treat the tower as a vertical beam.    m

  To make a secure fit, rivets that are larger than the rivet hole are often us9v f gd(o.:ftpm.k(azed and the rivet is cooled (usually in dry ice) before it is placed in the hole. A steel rgko9dzaf(fp. m.(v:t ivet 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 zlt 3gu* 48o 4rnbx)coat 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 dis7ph6y hrx9y: ameter. What will be its change in volume if it is hxr7yp:hs6 y9 heated from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim zuwl 2us,2r o: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 55.50 mL djh 5xq9x5fq:+ v7jt sof 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 ring made of iron. At 2iug )svk),ff;aglu(sx( 9;uv 0 $^{\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 lopbemt : ncs ut2,lnsw (7)o;l9ng, narrow vessel so it can expand in essentially one direction only, show that the effective coefficient92s:n eobp 7u;lwtnl tsm,)c( of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change i.xpycj. i99lqsu 8w yvymn;(4n 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 of5hd .h8kqdo s1gjl4dt) 4 7*3qro4h-qjy veil length l and width w has coefficient of linear expansioj 1 o hqqvk )y54j*egdhl3si7dqlo.d4h4r-8 t n $\alpha$ 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 x6zhy6fc-m2 p 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 perfectol 4ldk.4d +hklvw.pb+bft / / time at 17 dkwt+/l+/ fd.l bo4k bl.v4 hp$^{\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 diameter of 0.140 mm. The b l;0f,xcnsih +s6*vla ulb has a volume ofax0vl*,6+ l ish cn;fs 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 rotgckd550 z1rtc(+v3 yjlx*xyjwgt 3.w ating about its axle on frictionless bearings with angular velociyd*cgw+lj03yc ( 1g5z xjr k3wtx5t.vty $\omega$ = 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 kf8* mrlj/e)ld z9 :cu,odk2g9f vyh8stress is required to keep it at this len)vdo /keduk fzhr9g l9*fj :2yl m8,c8gth if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cro1j x386phi ;krm,xafass-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 134.122 cm at 4jz2b;ot gr/i20$^{\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 tfwr(c+kq(m33ff( axzemperatures 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 thk)m4u.up h9uci w*lp0 e Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun are about 40q98ye uoc k2pv+:v m-w00$^{\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 ank(rq :* 3 : 8eyvtd)zgdr,ndlhd a temperature of about 2el ):(z3 hv* gr,kddnq8r:y td0$^{\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 idtg-;bw xt )zwe( :k fo9tbd(5meal gas law.    kg/$m^3$

  A storage tank contains 20ehz 3xg 3 :p8-/lu dc(ztqt;zl: ihxt1.6 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 8pa;h-b(r fyps+iuq3 qo9ga .h*:goyj;h b4g contains 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 gacf 6 (ezqetr92z52k ;v2sila ms 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- aw ;s4dxdtx0 35.0-L container holding 105.0 kg of argon gas at dd w; asx4tx-0385 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0y( j:*:u6 zt1bb. qfruasasd: kg of $O_2$ gas at a gauge pressure of 8.70 atm. If the oxygen is replaced by helium, how many kilograms of the latter will be needed to produce a gauge pressure of 7.00 atm?    kg He

  A hot-air balloon achievvtpu tn8q.at .q:p(n8nl ou fx6.swwd1ay 099es its buoyant lift by heating the air inside the balloon, which makes it less dense than the air outside. Suppose the volume o910uw6. onw a.8q:l.xtadnyftp(up tvsn98 qf 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 vr6ziw pyi h7fc/6u9i jvg/ qthf6(+915 $^{\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 18qcqm ) l9 * 8/2w4wr,,shz6rmkkbcphj .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 eq z wge q8x,dnndq*873.8 rjttscapes 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 / hb4prlty (e: m;qi4w924c kre $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are thereos vbes.zj/ : nxt4t(9 in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number o (1pktsu ht3b.dx0, kgf (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 volume 5.1zga /9ibg)q a11: vmqx$ \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 breatpy:h )h0. mluyqq,xjgi+e) 8 bh you inhale that were also in the last breath Galileo took. [Hint: Assume the atmosphere is about,qj8q h)xlum.hp i)y e y+g0b: 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kineticy my6mms1yo5n+cj+ydl* g*dk;p s03 y energy of an oxygen molecule at STosg6m1y+yyjyd* kl50p ;+md*sc3 ym nP?    $ \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 teu )h).enz tgk/mperatn z) ue/gkh).ture of about 6000 K.    m/s

  By what factor will the rms speed of gas molecules increase if the temperature iw f-mt9 mkanit+go jv+pf8/ -9s inc9pw kifo/mj+m-f9t-a tv +g8nreased 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* z3b svztxq8kfyb0*5fh q(mz5xjm/ . speeds, given in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calculate the rms speed./b 8jy(x t5k xmq53z*msf*hvz zf .q0b $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at c rm06.vg-q53kgspi ye maz/wb79n u-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 douixnkdh,-b4w+ v,i m:sbled while its volume is held constant, by what factovd:, 4bsi wnxi-khm,+r does $v_{rms}$ change?   

Show that the rms speed of molecules i 9jm d.ietca+9n 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, the.,ivsj4p( didbi vc() lbhq4, ratio of their rms speeds is equal to the inverse ratio of the squarb ,.4ivdsjp,bl((i i cvd)q4 he roots of their molecular masses.

  What is the rms speed of nitrogen mon2 92r o9eg ;;wv6tlqp) x-rlvtckvl,lecules 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 ofy ;rk8 glese(xi ,*k4i an 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 nitrogen molecuif.yfss i +e4 kj(6d.oles at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed oq99d yv,wc k 7,vapxp)f an amino acid whose molecular mass is 89 u in a living cell at 37 9dpa7),9 qwyvvk,xp c$^{\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 written cjc8h2 dg)c:/,k)8 k jre1l lxi6lxzyP = $\frac(1)(3)\rho v^2$ where $\rho$ is the density of the gas and v is the rms speed of the molecules.

  The two isotopes of uraniumvbs3)ag7wc 0gcl)* hd , $^{235}$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 caczxdy4be.3( gq6aq7- sxk 1xa n $CO_2$ 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 0v87+z 6vp y1e7mzhww k.01 atm and the temperature is (a) 908vkw+v epmh7z yw7z1 6 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (appr1+.v: 3p9gio zil*lnfd*xwo joximately) if the humidity is 50% on a day when the temperf i9wdnjo*1vi.z+g: *lop3 xlature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where w6. i lv0eiiaa;ater boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the t5wtdsf6t. ct m2b-/dvng :bbgc 56p4mountains is 0.72 atm, estimate the temperature at which ptctnbf:dmtdb5g6 sg56cb2 /4 v t- .wwater boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pr bux5zzr)r+/poyrl;) essure of water is 530 Pa and the relative humidity+/xz;bp5r z)r uo) rly is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the temperaturz dxyjlxc8yu, .(q8u9ix / (yxe is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cooker if the w,1kw jr, jjfj2j dc7j:ater is boiling at a tempejj 1,dj2k7wf jr,:jcjrature 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 v6wnwh;yp 6eu d1v 8sdr+/g9fxolume 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 poinica 8rwxtlh1jh/8ei:gz 7m53 t 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 mog /g7ubqdp- , xwl.rd;lecule (see Table 13–4) to diffuse a diswgq /dgdx.u7 lr;,bp-tance 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 tlbv9 k(g u1py )07 gcv)atqoh9o the interior through tiny tubes called tracheae. An aver t)l()ucgy7kb1 o 990ah vpgqvage 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 me1kg,t6k oj yk1 z+kd*sasure 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 bee n/h3ds h x0c-k0gjk6vn calibrated at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A Pyrex measuring cup was calibrated at normal room t1a btqam,a p,-. . uehz86nfzl 7m5mliemperature. How much error will be made in a recipe calling for 305l, i., m-hqf.ae6at abzm81nzuplm7 0 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 gaj ctqvz7 .hyafaw;;(w3(,p+ (g qgf 2pw* uiwts cylinder is initially 28 atm. After many balloons have been blown up, the gu gw,p 2+3i*h(. w twwzf( 7fcgjvt;a payqq(;auge pressure has decreased to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air mgb q -d*t+t6vwolecules in a room of length 6.5 m, width 3.1 m, and height 2.5 m. Assume the+bt6v w*-gqtd temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is about one atom per x 2s 8,k*lsggp$cm^3$ 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 ps1np4 g3 bm8lthe best available vacuum techniques is abom 8b s4p3nlgp1ut $10^{-12} N/m^2$ 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 lung p)1exwjt+ mp/s to full capacity of 5.5 L when 10 m below the surface, to what volume would his lungs e+xtj1wmp )pe/ xpand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning fib t)a/du1ebk 619mq arom the 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 correspond to ) 6m9ab1i/deb qt1kua 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 increased sle xfplka-+q:qd( 1; 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 77edyqujgfle(r; h 12/+ 0m$^2$ (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 ay.p kj1cnl cmr-9e25 mo3vfa ge (zo*/tmospheric pressure at the surface of the Earth, estimate the total number of air molecules in the Earth’s atmo lpv913e(2*.c fcj ym5 mzrna-k/ogeosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules 4eu jh(h7e:s6:: ggfvkmbne1 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 usedmc dqtk uk v5;)9b+z(z in a hospital has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if thvt cz(b; kqmz5k9du+)e flow rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in 1,;e re:hvk+8,tbi7rjisr bsa bowl of liquid mercury at 0$^{\circ} $C. (a) If the temperature is raised to 25$^{\circ} $C, will the cube float higher or lower in the mercury? ----待选择----lowerheigher 
(b) By what percent will the fraction of volume submerged change?    %

  The density of gasoline -zgffa +j+ ns3i 5o8juat 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 ez /kml /ghszq ca4+w(5rxwrkmi l.2r0g 2yz, 1quator 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 jar azq9rfx6 3mlnddwfzs :ii/bg:0 3i/ h,t 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 thcu9vzb2kz:woyjg(mo+ wgyf: 30s*l f p*1z.k e 18$^{th}$ century, was a platinum bar with two very fine marks separated by what was defined to be exactly 1 m. If this standard bar was to be accurate to within $\pm1.0 \mu m$ how carefully would the trustees have needed to control the temperature? The coefficient of linear expansion for platinum is $ 9\times10^{ -6}C/^{-1}$. $\pm$ =    C$^{\circ} $

  A scuba tank, when fully charged, has a pressure;l6 svw ,d 98v95fdoxspc )rte 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 tl9oyj 83acg,ycgz62f bc9t ht vs 467;dk1iwrhe Earth 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 1nxw 05a zucq-/.px rx*ld/xdballs thrown vertically upward at it. How many tennis balls per second must reboundz*- /r1xa/.xlpu5d c xnw x0qd 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 (sphe1i ttfhy kghs-;l*yg-d)hw82:png hn+ qs3*r rical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the air behavesdfh -3sy glk*ip )hh-g*ntrstq + 8g1hnw2;y: as a perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total :i fri8med2wgj g raq5s8(3,nwater vapor pressure in the air on the following two days: 8n5qj2g3r (gwrf,a:i8ds iem
(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 l *m )0ddh/s,wx tad)pof iron at STP, and when it is a solid deep in the Earth where )dhd0s m ld/ xt*),awpthe 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 g 36g, 2px9ek -s1ug+kwt1i 6p asjoybfas at constant pressure, th- fsp6 p1+gew93bx u,1k6jyg a2isktoe coefficient of volume expansion is equal to $\beta$ = 1/T where T is the temperature in kelvins. Compare to Table 13–1 for gases at T = 293K (b) Show that the bulk modulus (Section 9–5) for an ideal gas held at constant temperature is B = P where P is the pressure.