Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodic 2 .:j 8z; ergjelbrm5c9f fbq)table orlczj:erg fmf 8bj2b.;9 eq5) r Appendix B.

Name several properties of materials that could be exploited jv0 ,c2p)ra rkto make a thermometer.cprv0 a) r2kj,

Which is larger, 1 C zscp 8c unqp)+(wfa6502 tvva$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with syste va14ulu +q+n v xg,fx2e. d j65xfno,dqdql)1m B, but B is not in thermal equilibrium with system C, what can you say about the tem)q,exofl2q4d l.5f+auvg nun,vd6 x j11q xd +peratures of A, B, and C?

A flat bimetallic str9n(z0 9xc-;f1 da7gxqq phgnu ip consists of aluminum riveted to a strip of iron. When heated, the strip will bend. Which metal will be on the outside of the curve? [Hint: See T9 -1znpfn;hg79 xq0cu d(qgxaable 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 expansi27g/*.r) smb qpuvd:wnrjv* bc 2a1x son $\alpha$ 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 63q+xy; jap mx ba7-0ueueq (sof a simple thermostat used to control a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bond xpa73 beqy60;x+su-qj(a uemed 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 at different temperatures.

Long steam pipes that are fixed at the en6w*aegn 5rm/bi4y xw 4ds often have a section in the shape of a U. Why?/wgr 6nyw ax 5m4i4*be

A flat, uniform cylinder ofrq:13f7x qi qelq x5-f lead floats in mercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometer is first place 2swp+vaw1w,uud d b75)jjkd:d in a hot tub of water, the mercury initially descends a+u2dw dv,:jw)ksju bpa d5w7 1 bit and then rises. Explain.

A glass container may break if one part of it is he7 sqrrpka j0,9bj6f 60 fcbv1sated or cooled more rapidly than adj1s 0f qa669jj7 c0 fbrrkv,spbacent parts. Explain.

The principal virtue of Pyrex glass is that its coeffic*)b9fqh q q.zyient of linear expansion is much smaller thanb)9q. y*qzh fq that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurate ;xg8xw,s8svs +rzbr d 2o28woat 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 causc4cfdei5 7p y7e its bottom and top to bulge so badly the can will not stand up. What has 57dc epfi47c yhappened?

When a gas is rapidly compressed (say, by pushi.9:w b lty/ eor+zg t8e8tu/27uwimvdng down a piston), its temperature increases. When a gas expands against a piston, it cools. Explain these2/i 8 yrwumetz 9tb/ol.t: w78 g+eduv 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 increase or ef y1 z 57sl ug5j ;x8cegzr598gbbig9 *:xkeldecrease if the temperatury: l5x8b5gk 8ib* gs5xcge lj 97r u;ze1g9ezfe is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Chaik37yvg 2se+ b)td/fee by7o4rles’s law follows from kinetic theory and the relation between average kinetic ener ds kefy4gi b7y7) 2evb3+to/egy and the absolute temperature.

Explain in words how Gay-Lussac’s law folz mdsn l z3)o,p+xw2d-ew)w, tlows from kinetic theory.

As you go higher in the Ear+c(z -:/ah-aachrb.d n fc/ xxth’s atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimu p,fm ah r 2,dxmr s5-pr6on8kk-yd4*4pyw3d fm speed an object must have to leave the Earth and never return. The escape velocity for the Moon is about one-fifth what it is for the Earth n,d p4* ,8fh- y6pa d mwdyrx5smk-rp3rf4k o2due to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at vdvtsm8y)g * )room temperature. What can you infer about the molecular properties of one relats)) vmt*gd vy8ive to the other?

Explain why a hot humitu,fbe6 duk4+d day is far more uncomfortable than a hot dry day at the same te tbu,u ek4fd6+mperature.

Is it possible to boil water at room temperature (20 t ;kos-zcdgs5rkn./7$^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the humidity zk3gu,p 5 d,zz22yuxygo 4ok*is different. Which is more dense, the dry air or the hu dzkg xpuz4gy2ok,*zoy532,umid air at the same T? Explain.

Explain why it is dangerous to open the raq6qk n1;mk.6/ brelc fdiator cap of an overheated automobilemkf b6/ln.eq1;rc 6q k engine.

Why does exhaled air appear as a little white cloud in y*j3d e 0p5zlvthe winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram i3 lwwovwc.90copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of6 ubvq(s/b;tv 18 yazz atoms in a 26.5-gram gold ring compare to the number in a silver ringvsuztzb1v / 8ya6( ;bq of the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this on the Cels son s7:85nplbius scale?b87osp5: n nls   $^{\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 temperaturm ;/uy(vrr l: i6zzl4les 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 col* : .ks+rot .rj5,tcf-jummyl umn has length 11.82 cm at 0.ml. rtrk o+tu5 .:sm*y, jf-jc0 $^{\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 (2;bbqw7 n(r2 ab0 $^{\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 wrou 8/t0(w adu 3m8sbtiwyght iron approximately 300 m tall. Estimate how much its height changes between 8wattbs w 0ium 38dy/(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 large3ms 9zb * usfo)y.kh;;aq6c cur than the rivet hole are often used and the rivet is coo;cq.oz;)ms6 9 hs *3uyuakc fbled (usually in dry ice) before it is placed in the hole. A steel rivet 1.871 cm in diameter is to be placed in a hole 1.869 cm in diameter at 20 $^{\circ} $ C. To what temperature must the rivet be cooled if it is to fit in the hole?    $^{\circ} $ C

  The density of water a:; o9h 1o,v.qn jwux7 uo+mbfht 4 $^{\circ} $ C is $ 1\times10^{3 }kg/m^3$ What is water’s density at 94 $^{\circ} $ C?    kg/$m^3$

  A quartz sphere is 8.75 cm in diameter. What will be its ch5: skce2,qo03rl3zcr ol /gm+ro z;x wange in volume if it is c0sx33;5 ,omqzoz kllr:we2r og+/rc heated from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350.0 mL of water at 10h,b 1zis/5 wj7bhwzwp;,d 6 lt0.0$^{\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 e,b;o jr,nvmv/mb.+w0fiad2 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 ringea:4dt6ay4 b9pk v12r my4wqm 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 :v ;-+ffsjgydsf,c9b0 3k 2cpyvds/v long, narrow vessel so it can expand in essentially one direction only, show that the effective coefficient of lid3s -y:scfgyc9fdk,v0 +j sfv/p;bv2near expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the density 94ya kg n/5rwq$\rho$ of a substance, when the temperature changes by $\Delta$T is given by $\rho$ = -$\beta$$\rho$$\Delta$T
(b) What is the fractional change in density of a lead sphere whose temperature decreases from 25 $^{\circ} $ C to -40 $^{\circ} $ C？

A uniform rectangular plate of length l and width w has coefficient of linearm8r j28u kba6a expanj 2bauamkr88 6sion $\alpha$ 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 isot7 rqkn h75xx1zropic 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 grandfloe3d0wko/5tx) xgpj si*m 4gx l .2j6ather clock is made of brass and keeps perfect time at 1xm. gip 5twos*jkx)46g2 oljxdel 0/37 $^{\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. Thefc1,dj:g aw2 x bulb 2xf1dg :,cjwahas 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 cyli2 mu,g+xeeitg ;e6c e.ndrical wheel of radius 0.41 m is rotating about its axle on frictionless beat+mg ce6e g;e. e,i2xurings 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 lengt e3nny l-f+. 3tdg(:eyhlq. fj3 fl6oih when at 15°C. How much stress is required to keep it at this length if the temperature in6d(teil:n n3qy llyf.f -3 3g.h+f ojecreases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam om8 9iwcvu o)i)f cross-sectional area 0.041$m^2$ is rigidly connected to two vertical steel girders. If the beam was installed when the temperature was 30$^{\circ} $ C, what stress is developed in the beam when the temperature drops to -30 $^{\circ} $ C (b) Is the ultimate strength of the steel exceeded? (c) What stress is developed if the beam is concrete and has a cross-sectional area of 0.13$m^2$ Will it fracture?

  A barrel of diameter 134+ad+v/0 tnkx f.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 followinuvqv;vk4dx) v;y ax 0-g temperatures 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 Fahrenhe: ru7hu/p h :e.k*sltutd 7fn(it scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Eart + kzk 1le*,iy*bzkon)h and Sun are about 4000$^{\circ} $ C and $ \times10^{6 }$ $^{\circ} $ C respectively.
(a) What are these temperatures in kelvins?    K    $ \times10^{ 6}$K
(b) What percent error is made in each case if a person forgets to change $^{\circ} $ C to K? $\approx$    %(Round to the nearest integer) $\approx$    %(Round to three decimal places)

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

  In an internal combustl5 i(qde(lttf 7qce9,ion engine, air at atmospheric pressure and a temperature of about 20 (ftlte 5l,7 d9qi(eqc$^{\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 oxygejzh76 qta:b6h zzn04e n at STP using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of n +tq7(,k1krt nf;ey;p8pm32yxqrcm m itrogen ($N_2$) at an absolute pressure of 3.65 atm. What will the pressure be if the nitrogen is replaced by an equal mass of $CO_2$    atm

  A storage tank at STP contains 18.5 kg of nitrogewzo 10 l(t;asen ($N_2$)
(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 ga1t-kr 3hsbp y7s 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 holdinglit hngbj p4fu**h -x(dev,: - 105.0 kg of argon gas at 3 dix-lefn* h(-h4uvbtgp :* ,j85 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kgqzry+fz, 4s wz6:z:7n+ep twi of $O_2$ gas at a gauge pressure of 8.70 atm. If the oxygen is replaced by helium, how many kilograms of the latter will be needed to produce a gauge pressure of 7.00 atm?    kg He

  A hot-air balloon achieves its buoyant lift b1jaiexm6y lxs 4b* (ky-e*x3ty heating the air inside the balloon, which mak*x txi1xybjlm y(64 sa3k*ee -es it 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 air at 15nxtlzs:7u v(6 $^{\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 atw96 h)uaf-u2 ulwheuc h5j:0 s 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 nq.xj98ciq z:w/xehh 0 ut0+r 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 numberks2xnxj4emp4tf 1a 1* f gx8,hnk2 i9z of molecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are t(bdznb;d x1 d+58quyvhere in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of m/gx lmo:k *7n(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 5.1ncbh5(d(bn) ltkl74x8 pl v,b $ \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 a*sd :g pa7fb:rir are in each 2.0-L breath you inhale that were also in the last breath Galileo took. [Hint: Assumdg 7a*brsfp: :e the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kzx /h66uhiat ad.6kc (edno,h j0c/1 oinetic energy of an oxygen molecule at STP?o z,uo6j(1 canhc6 dhtexhi0//6d .ka    $ \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 temped9 yh-j1j87n e5zk2 xpncw-h zrature of abkd e c 2-zpx1n98 zhwj7hy-nj5out 6000 K.    m/s

  By what factor will the rms speed of gas molecules inclvgc cr5 7)q45xxj(d lrease if the temperature isx v5c5gcdlr qxlj )(74 increased from 0 $^{\circ} $ C to 100 $^{\circ} $ C?   

  A gas is at 20 $^{\circ} $ C. To what temperature must it be raised to double the rms speed of its molecules?    $^{\circ} $ C

  Twelve molecules have the following speeds, given in ueowrzzzz57 f h0/jf9: nits of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calculate the rms sprz f :h 0z75o/wezfj9zeed. $v_{rms}$ =    km/s

  The rms speed of molecu(b khy-rqtl.ay3 g3559 zop jqles 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 doubled while its volume is held consta ,hv/gq7f f7pi/. upg q/iis8nnt, by what facto. f,iqs g/n7 7pv hg/fip/i8uqr does $v_{rms}$ change?   

Show that the rms speed omgn4pxb6yd njy:78-85th adh f molecules 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 temperature, the azrf* oq.3e:j ratio of their rms speeds is equal to the inverse ratio of the square rootsoefa qj*:3 r.z of their molecular masses.

  What is the rms speed of nitrogen molecules contaq4hyjg+mqsygl r 8m:u( ,b*wg9b1*dnta r+8j ined 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 oxygeh9 40clzx6k9.j s ,akjqxbd v*n 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 molecules s+u2, aip ;jwqat STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular mass is 89 utnmz21z :ghsezxu -,ns;x -;mjy f(p 0 in a living cell a21: -fxjz-, zp(yeg; nh0n ;xutzsmmst 37 $^{\circ} $ C.    m/s
(b) What would be the rms speed of a protein of molecular mass 50,000 u at 37 $^{\circ} $ C?    m/s

Show that the pressure P of a gas can be 1s+gv.ep) f jy +6lgfvhy b:joc1t a8-7wov+nwritten 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 uraniufyrnxzu 0oi 9 4nn223om, $^{235}$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 can +9i:+ed id2egux)cd k$CO_2$ 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 temperaz(xqatr *k/z .ture is (a) 9rx (a tq./kz*z0 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the huijmy e7;lf1a+ midity is 50% on a day when the temperature is 25 +;fy1e 7mijla$^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at oc9la-bd p dru5-80 rqa place where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in thes2h 6 8*amwvgd mountains is 0.72 atm, estimate the temperature at which water boils.av2h6wds 8m* g $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when trn. /tjpzux4-*omrxa4x (+pi5g2n yshe partial pressure of water is 530 Pa and the relative hrs-5 i*ju4xn4x p/+(a og2ny .mrxpt zumidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a yyp2 37tpgt*gfyrz25xyg :e re)0wz7 day when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cooker if ths q4,k/omp:k xe water is boiling at a temperatu/oxmk4p:s q,kre 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 volumd1k*br,qog 6olrl +, ae 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 poin(6r n v::cxc,9pv uqf*0bj50 2itwfa4rl kywpt 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 ne5ogx jsm-9y h+eded for a glycine molecule (see Table 13–4) to diffuse a distance of 15jhom s9 +y-x5g $\mu m$ 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 6h *b1iv3/fier d8p wgthe interior through tiny tubes called tracheae. An average trachea is about 2 mm long and has cross18pri3 d gefh/*biv6 w-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 6bn- di.t1(f)ysa sf 81 f-k mchm3skhbeen 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 calibrated at 20ul6vn:so5rf b( )x)yz $^{\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 mucd2x 3pj/qiv0g h error will be made in a recipe cal 23gdixj/vp0qling 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)bj:-* c ididk helium gas cylinder is initially 28 atm. After many balloons have been blown up-kib ci*:d) jd, the gauge pressure has decreased to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air molecules in a room of length 6.5m6d8 b 0r p5) pqpn7ycbucsbv8k42, pu m, width 3.1 m, and height 2.5 m. Assume the temperature is cubn ppc, k)u88 qms2 6p57db40yvbrp 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is about one a7mwm-as l/mc *tom 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 th)d 7i al/bc.f/pxduw/bp w h(7e best available vacuum techniques is abop ch/ i/w)bua.w d/(l dpfx77but $10^{-12} N/m^2$ 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 wh4/lpewyw.a d-en 10 m below the s edw-l4p ./awyurface, to what volume would his lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmosphere at a speed of7gop gd3ykg.6up wy ve56 f:b0 about 40,000 km/h Molecules (a:0kw b63p. dug5yyp67 gvfeogssume nitrogen) 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 i(/ c9gsbk2 ldcncreased 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 7g1)o; 4y- king5d,t,veib uip 70m$^2$ (a) What is the total mass of air inside the house at 20$^{\circ} $C?    kg
(b) If the temperature drops to -10$^{\circ} $C what mass of air enters or leaves the house?    kg

  From the known value of atmospheric pressure at the surfaceb3syqk4d dn-. ;+kzya of the Earth, estimate the total number of air molecules in the Eaqd ;z snb+yka4k-. 3dyrth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contained inib 79qhmq(xx+nq o6- 0pp46 bvorgyt 9 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 pressur g :sixsja)j-0e = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure, is constant at 2.4 L/mis -)sj xagj0:in. $\approx$    hour

  An iron cube floats in a bowl a5rp xxm3 iat;cb8-g nbrc*) .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 gasolfdvs)2fu 9 :hnm 39s( nzwy0zbine at 0$^{\circ} $C is 0.68$ \times10^{3 }kg/m^3$ What is the density on a hot day, when the temperature is 38$^{\circ} $C?    kg/$m^3$
What is the percentage change?    %

  If a steel band were to fit snugly around9anv1v1 iyxq . )psiy/ the Earth’s equator at 25$^{\circ} $C, but then was heated to 45$^{\circ} $C, how high above the Earth would the band be (assume equal everywhere)?    m

  A brass lid screws tightly onto a glass jar a/8jr)1-xmhjzk4fc /94 g ma,c mvcz.mkz/wmb 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, adop waq1tdjsd *u,v)ck94ted 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 fksad4qy.eg/g 8 u 2,bmully 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 Eart0 cs 0u7vquflk*-jpp67ph x;acc4ze1h 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 2yyim3efpkf eoyn/6/zn6 7m-balls thrown vertically upward 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 throyie nfz7m/2f-/ey pm66ny o3kwn at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter (spherical) bubble of air from ..fu5an t:wvu6bo ks *l*ya:ga 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 lv6bu.ya*u ka ts.:*g n:f5wowhen it reaches the surface?    cm

  Calculate the total water vapor pressure in the air on the fol0j79 rfnscyasa kz) -)lowing two days: )a )sz0a-kc jr nyfs79
(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 diffddn :l dt5m1yfkl(5q/erence in the density of iron at STP, and when it is a solid deep in the Eardltfm5lq(k/:5 dny 1dth 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 i 0 ndzz;y 96gkh q,,j2q 6ner7ote;mgz /v7xcydeal gas at constant pressure, the coefficienxzg/h6ck;o y7n 69v n tr;z,0z2ee,j7q qy mgdt 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 dehumid-po3sh 7wdq .oify their cellars to prevent rot and milo -p.d3owq7 shdew. If 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