Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodic tabl4kfg6bn*)kr 2s,r. wu v pl1kne orpw 4 kk6k*rngn)2f, svr1l u.b Appendix B.

Name several properties of-uaj u( u ec5.ytsypq9+y57oljfr-9/kccq d2 materials that could be exploited to make a thermometercjso-pt9+q97u/ cy5juef-5qc du( ak.ry y2l .

Which is larger, 1 C + 9v8syn9r7it r-iwvt*mi,gn $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B iy/3vy / quqol5s not in thermal equilibrium with system C, what can you say about the temp oyy5/ 3qvlqu/eratures of A, B, and C?

A flat bimetallic strip consists of aluminu6ahveyqq 4kt4r wzzt.()u r15m riveted to a strip of iron. When heated, the strip will bend. Which metal will be on the outside of the curve? [Hint: See Table 13–h4.6y)ze t (w r5vturqq 4azk11.] 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 coeo8*ke hy-k4yjfficient of linear expansion $\alpha$ are $(C?)^{-1}$ and there is no mention of a length unit such as meters. Would the expansion coefficient change if we used feet or millimeters instead of meters? Explain.

Figure 13–27 shows a diagram of a simplaf*tj b5,z0; at 57qgx9zt zmxe 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 5gtjtta*,mq b zx9z;z a7fx05wires. Explain how this device controls the furnace and how it can be set at different temperatures.

Long steam pipes that ari9esjh +lkn( onf5z)j r+r5-le fixed at the ends often have a section in the shape of a U(nfk55 9- lil++eojrnz j)r sh. Why?

A flat, uniform cylinder of lead floats in merc k,y.xp5p4u a anm;ot6ury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometer is first placed in a dlxfrly ej;ris( r8 hn4 u1x)81d5tih6:b je8 hot tub of water, the mercury initially descends a bit and then rises. Expl64s58in1f hj:j1;h b r)tlru(dle88 xxiyr deain.

A glass container may break if one pxduz*m-h/ - mzypu n:ru(4ai 3art of it is heated or cooled more rapidly than adjacent parts. Exp 3zpr--xyzu:4ad / umn*(huimlain.

The principal virtue of Pyrex g 1 x ./.1 6a7pexnn:tiykrtvcflass is that its coefficient of linear expansion is much smaller than that fo:kare6 x7/1pf.1. ixnyc nvt tr ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurate n b.)lcpey. u3 i56vbgat 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 it1 e kea*1q2dgvc(/yg ms bottom and top to bulge so badly the can will not stand up. What has happenggdv*1mc yq2 kee(1a/ed?

When a gas is rapidly compressed (say, by pushing down a piston), its tempw1cqf/pa i j*i,3 kk wg)6ceh/erature increases. When a gas expands against a piston, it cools. )/iaeiqkj 16/k3cwf, h *wpcgExplain 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 wag;kor 577rhhster increase or decrehr;hks57 og 7rase if the temperature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law6, o*wpmdna -;eg q9ls follows from kinetic theory and the relation between average kinetic energy and the absolute temperaturlp-, nm*;gd9qe wo as6e.

Explain in words how Gay-Lussac’s law follows from kinetic theu4;tcpep a*yjqf0:* jory.

As you go higher in the Earth’s atmospherekk oc-:apjk(a: + xub*, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed an object must l:sriy11 y 0qkhave to leave the Earth and never return. The escape velocity for the Moon is about one-fifth what it is for thyr1ly :ik01sq e Earth due to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at room temperatuy5( ,xtvlyexsev:, q ipt4j 9,re. What can you infer about the molecular properties of one rev4i: s( xv,y5qjttypl e9,,xelative to the other?

Explain why a hot humid day is far more uncomfortable 63/ycihyhd/7v ndur ;than a hot dry day at the sameu yd;/y idn/ hhrcv637 temperature.

Is it possible to boil wategfzny 71*d 2 1tw2;qvi my0folr at room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperatureh7*;edz- *fabiw,ol d)g tpd 7 is the same but the humidity is different. Which w,e7dd t7ipz )agd-l ;h*obf*is more dense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap of a gm bdr89ri-(4yh4sizd3 v 0gvn overheated automobile enginrvv9ihgd zi srb4-(3 g48md0ye.

Why does exhaled air appear as a little white clrk lk;nciihhxj1k2o-a e q;4v/-5z 4boud in the winter (Fig. 13–28)?

  How many atoms are tursprn21l 79rhere in a 3.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold 5xr.60yeumm f ring compare to the number in a silver ry0.6 5xfumr eming of the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is oggo +fg v.pj26 p* )jra-htfx:ften taken to be 68°F. What is this on the Celsius scale?+fjapg hx-g:j* r2 g6.v)tfp o   $^{\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 an hfcn m1,*cboc71fyi4d 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 z3xj/rcv 3un:95i*jut favb3thermometer, the alcohol column has length 11.82 cm at 0.0 9ac:jvutub r v/5n 3ifz3xj*3$^{\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 lon cfby9/rdw ;r l7 t0:3xn8wwjlg (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 apz ;:0 k1htrvqzproximately 300 m tall. Estimate how much its height changes between July (average temperature of 25°C) and k:zt0qrzv1;hJanuary (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 hole5v7dyp7vasx 5 /pll- admpd 6) are often used and the rivet is cooled (usually in dry ice) before it is placed in the hole. As5l)7x ylv76 /v 5da-p appddm 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 m3*vw dj4*ozht 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 wil,k0th79s e2y pmo33 ;zg:mft) l +cqzac8t zbgl be its change in volume if it is heated frm h;pkt39zetltb: c fz38s)m g+ 0a,7qg2co zyom 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 athb8.p pw0;jia 100.0$^{\circ} $ C. If the temperature decreased to 20.0 $^{\circ} $ C, how much water could be added to the glass?    mL

  It is observed that 55.50 mL of water zmk q*sl00yck, 0sz-w 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 6;1-buff,30qpacdhe)q*lgqk5f u il a ring made of iron. At 20 $^{\circ} $ C, the diameter of the plug is 8.753 cm and that of the inside of the ring is 8.743 cm. They must both be brought to what common temperature in order to fit?    $^{\circ} $ C
(b) What if the plug were iron and the ring brass?    $^{\circ} $ C

If a fluid is contained i..qlqbit up*p3zn9 )yn r+ xvv/ 6;cbcn a long, narrow vessel so it can expand in essentially one direction only, show that the effective coefficient of linear expa npbyrbc. /.9v3x u+t *q)ic z;6qnvlpnsion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change gu+p5vc*th3 i in the density $\rho$ of a substance, when the temperature changes by $\Delta$T is given by $\rho$ = -$\beta$$\rho$$\Delta$T
(b) What is the fractional change in density of a lead sphere whose temperature decreases from 25 $^{\circ} $ C to -40 $^{\circ} $ C？

A uniform rectangular plate of length l and widt- 0m: cfzth,9 g2wrjcsh w has coefficient of linear expanscmwcr , 0jsf9zgt :2-hion $\alpha$ 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 ,n+ cz*f*/ bn/r jd8je5afwcjsolid, $\beta$ = 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 braqn m-5f3 cpx. 2w*ldqxdqi(0-jo pxu3ss and keeps perfect time at 17 nfp 3d5 q(cmx i3p- -0uxlxdw.o j*qq2$^{\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. l18qd*k y ,zewThe bulb has a ydl wq8ke z,1*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 i(k xsilz3o4 35:zlvwws rotating about its axle on friwl 53i(lxk3w:zvs4zoctionless bearings with angular velocity $\omega$ = 32.8 rad/s If its temperature is now raised from 20.0 $^{\circ} $ C to 75.0 $^{\circ} $ C, what is the fractional change in $\omega$?   

  An aluminum bar has the desired length when at 15°C. How much stress is requij2/;q9bhy7xjm ;ghkhaz.t * s vxe* s;red to keep it at this length if the2ts b hjkqmv;x*;g s;ejz h ya/79.xh* temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-sx-1p5bvfi+l2 uxs ff5 w7x)z oectional 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 2lio;6zq2cgxe a1vq c2 5fk08k 0$^{\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 t*5yp /s7xfiy9ffa/y6a u ; hvnemperatures 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 temperatubv5y 48xzqea,re on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earthvfzg7g fm, )a+ and Sun are about 4000$^{\circ} $ C and $ \times10^{6 }$ $^{\circ} $ C respectively.
(a) What are these temperatures in kelvins?    K    $ \times10^{ 6}$K
(b) What percent error is made in each case if a person forgets to change $^{\circ} $ C to K? $\approx$    %(Round to the nearest integer) $\approx$    %(Round to three decimal places)

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

  In an internal combustion engine, air at atmospheric pressure and a th ajw.w )2chq.emperature of aboutwa h .jqc2)w.h 20$^{\circ} $C is compressed in the cylinder by a piston to $\frac{1}{9}$ of its original volume (compression ratio = 9.0). Estimate the temperature of the compressed air, assuming the pressure reaches 40 atm.    $^{\circ} $ C

  Calculate the density of oxygen at STP using the ideal gas88axyk dlsgj0p v 3d02 law.    kg/$m^3$

  A storage tank contains 21.6 kg 6d xd6cf(y 7ulof nitrogen ($N_2$) at an absolute pressure of 3.65 atm. What will the pressure be if the nitrogen is replaced by an equal mass of $CO_2$    atm

  A storage tank at STP contains 18.5 kg of nitrogen.hyf+uhfnkiq7v 1/ n/n )rcusmxn46 * ($N_2$)
(a) What is the volume of the tank? $\approx$   $m^3$(“Round to one decimal places)
(b) What is the pressure if an additional 15.0 kg of nitrogen is added without changing the temperature?    $ \times10^{5 }$Pa    atm

  If 18.75 mol of helium gas is at 10.x438 w1mn5 d ytm,ljyg0$^{\circ} $C and a gauge pressure of 0.350 atm, (a) calculate the volume of the helium gas under these conditions.    $m^3$
(b) Calculate the temperature if the gas is compressed to precisely half the volume at a gauge pressure of 1.00 atm.    $^{\circ} $ C

  What is the pressure inside a 35.0-L container holding 105.0 kgd yc nu*axut3 ys9kl )i6/573uagjxk , of argon gas at 385l*y7kc ju5u g63ix a/)tn9duy3kx,sa K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg,2p m,ww j,slx u;*aif of $O_2$ gas at a gauge pressure of 8.70 atm. If the oxygen is replaced by helium, how many kilograms of the latter will be needed to produce a gauge pressure of 7.00 atm?    kg He

  A hot-air balloon achieves its buoyant lift by heating the air inside thw*oir27. oej be balloon, whic.i*7j boe2 rwoh makes 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 withqzyv: 96dz9su air at 15 $^{\circ} $ C to a gauge pressure of 220 kPa. If the tire reaches a temperature of 38 $^{\circ} $ C, what fraction of the original air must be removed if the original pressure of 220 kPa is to be maintained?    %

  If 61.5 L of oxygen atk/:jbig dk,.7s q4,lyz 8sbm l 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 2rv,exiq cl2o-7 kt ;n*0.0 $^{\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 / v(sl5; l6.lx gyw: kmq$m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water ar*hjhh.ngd )dk: ys+a:e there in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) mr5+lclf zp(f**qmk / koles,    $ \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 ph;v3+/ zlv erj ,9uvbfa/2rz5.1$ \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 werenjjyugxm*p .y7 ,v-1 .wr( jhp also in the last breath Galileo to ygp1jj p.7x.r* h(uvn-yw ,mjok. [Hint: Assume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of e6l8wmve*gm9)g0sv x an oxygen molecule at STP0xg msg9m*w8v6 ve) le?    $ \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 s5ffcke ol u;70p) zh e:hbn1(temperature of about 600pu z:0h5 ) 1eeh(sfo lbk;7fnc0 K.    m/s

  By what factor will the rms speed of gas molecules increase if the tempecwv1 (dl:p ljq32x+tds 5 tf5brature is increased fro5+d(5 tl f2lb3xdqjwt:c vp1sm 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 unie*dhm j/lygvc6b43s,ts of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, ay 3d,v/ e4h*sgljbmc6nd 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules int*yer-i;f w e9 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 cons.ivpohs 6;3t1bsgjz*nq9 +jm te* w c)tant, by what facto j*6the;sw*1 iom) gcpv+3b.tz q nj9sr does $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is gi(3 gn20opv)dyap 0r/5jfd vy d.cjc3vven 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 gasem)t+3k 8zzft9zdtbj8 s at the same temperature, the ratio of their rms speeds is equal to)ztzt93+kmf8 dj 8z bt the inverse ratio of the square roots of their molecular masses.

  What is the rms spee u5lf): fqy qp-pqx,+fx/xx o m9e.x7dd of nitrogen molecules 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 rmf*2s9r jp0op-an ng,os speed of 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 molecules afm zd./ 2n-ngtt STP?    $ \times10^{-9 }$m

  (a) Estimate the rms sp1 lq2p4- ad9o ky5zf6oo:wtu42u ,wdmgz sv/ deed of an amino acid whose molecular mass is 89 u in a living cell at 3m 29ds 1dog4oa v:zkduwwqz-2oy/ u pl46t5f,7 $^{\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 n4(:sw)bpc/ any k3: rbj7qqyof a gas can be written P = $\frac(1)(3)\rho v^2$ where $\rho$ is the density of the gas and v is the rms speed of the molecules.

  The two isotopes of uranwn46z8fnrc 3 vtcx*t2ium, $^{235}$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 phassbe *ox+thg ,wx5l y(d(.ms 9ges can $CO_2$ exist? (b) For what range of pressures and temperatures can $CO_2$ be a liquid? Refer to Fig. 13–21.

Water is in which phase when the pressure is 0.01 atm and the tem wx ,ok9z4,x.0 sf xdgmqm-b9kperature is (a) 0d9xg-,z4k skfx,m 9q .o wbmx90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity is 50% on a uofijd7-;.v-n. swb gday when the temperature i-b-j 7ifw vsd.on;. gus 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where a a4ew*2ghi6p 9 eh1hq+raq 4qwater boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is 0 jwewlpinq,9ou 1wp o ex )sj82in1617.72 atm, estimate the temperature at which water boils.no6jj1w , n11expulqww8) ieosi p72 9 $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the part6jjsdo 9g2qkv, ys0 ras*40mbial pressure of water is 530 Pa and the relative humidity is 40%? 2s0jo smryvjb94s*dkg 0a,6 q $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial presbr-e2pv k8n t8sure of water on a 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 thepbng 0z j0 shad;oe3)0 f/bkc1 water is boiling at a f0ej bhcaodg b30k)ps;z1n/ 0temperature 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 volc-sl j3h9w*pi8u1 p q.wket9bume 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 poi,+go b6aoh 8 dv-5lcgr:qp (mant of 5 $^{\circ} $ C is drawn into a building where it is heated to 25. What will be the relative humidity at this temperature? Assume constant pressure of 1.0 atm. Take into account the expansion of the air.    %

  Estimate the time needed for a glycine molecule (see Table 13–4) tonthtd7 )+v 3o/cocc4v diffuse a distance of 15t/c t onv)+743chvcod $\mu m$ in water at 20$^{\circ} $ C if its concentration varies over that distance from 1 mol/$m^3$ to 0.4 mol/$m^3$ Compare this “speed” to its rms (thermal) speed. The molecular mass of glycine is about 75 u. t $\approx$    s ([color=rgba(0, 0, 0, 0.85)]Round to one decimal places) $v_{diffuse}$    $ \times10^{ -5}$ m/s
$v_{rms}$    m/s

  Oxygen diffuses from the surface of insects to the interior through ti5+l v/op7kphony tubes called tracheae. An average trachea is about 2 mm long and has cross-sectional +lokovp7/ 5 pharea 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 measu r:mf 6o9iuxu)vwb qv;c g-;-loe8f1are has been calibrated at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A precise steel tape measure has been calibratedmc9o5u * nnh/i at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A Pyrex measuring cup was calibrated at normal room temperature. m5 o5l tkuw)n2How much error will be made in a recipe calling for 300 mL of cool water, if the watew5om tk)n5 l2ur 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:glssl d j+/ar:cgq9 6 gas cylinder is initially 28 atm. After many balloons have been blown upr/glas9:g sl qj+dc:6 , the gauge pressure has decreased to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air molecules inrdgab 0kw:a69 a room of length 6.5 m, width 3.1 m, and height 2.5 m. Assume the b90adk6g : rwatemperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is about 6o:1xkwmka/ypf op- ,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 availq; c,w 9e4sd6l.73:eo xo kz1xkzbzguable vacuum techniques is about 3;u swx., zzz obqkxk971:legod64ce $10^{-12} N/m^2$ 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 wh :e+ y:7qswjaxen 10 m below the surface, to what volume would his lungs expand if he quickly rose to the surface? Isx7s :wqy e+ja: this advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmosphere at a speedf +*e mkn);f nqx/; rnjve54re 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 vehicle must be made of special materialsvnm* qx ;n)+f r/e4n;er 5fkje; indeed, part of it does vaporize, and this is seen as a bright blaze upon reentry.)    K

  The temperature of an ideal gas is increxx;:yu je vi;*c5szo,ased 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 ofbgf9 fhnhy 48+ 770m$^2$ (a) What is the total mass of air inside the house at 20$^{\circ} $C?    kg
(b) If the temperature drops to -10$^{\circ} $C what mass of air enters or leaves the house?    kg

  From the known value of atmospheric pressure at the surface of 4fx+r )ncsf6/eqx+f9.er ed ak)y,k qthe Earth, estimate the t4ka9fqe r))dre+.kx/ync6qe, f +xfsotal number of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen moleculm 8 )a vmlu0mngoo1/:;ezup2 aes 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 aw w0uz0+k3 5nugi70 ja,n rouin a hospital has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure, is cons nauo75,30i+ zkurng a 0u0jwwtant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liquid me- 2y9q-mndf fyrcury 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 at 0/e3g2h;8eb78+- ixnfh l msb rz*aoae$^{\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 a*dnw5cj1bbz 5 round 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 jqmj7i;)l x)auar 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, adoptq f ,y 5i i97hypfpha6knd)k,b o6,h5sed in the 18$^{th}$ century, was a platinum bar with two very fine marks separated by what was defined to be exactly 1 m. If this standard bar was to be accurate to within $\pm1.0 \mu m$ how carefully would the trustees have needed to control the temperature? The coefficient of linear expansion for platinum is $ 9\times10^{ -6}C/^{-1}$. $\pm$ =    C$^{\circ} $

  A scuba tank, when fully charged, has a pressure of 195 a 7zyqfb.)m/fnv l1-( ub w7oajtm 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 Ea+rhrmfjw i80fy75: k2czq ;f arth 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 lidc4:4mbr*)mybgyhy p + is suspended against gravity by tennis 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 arp4b :4cg*yh ) +yrmmbye thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-c+vh ox97zm7o;y(e equm-diameter (spherical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the air be+ myu7ox (7ezeq;hv9ohaves as a perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure in the air on the follo/m8vxt6h;c( pdxv dj7 wing two days: t xv/x;d 6djc( hp78mv
(a) a hot summer day, with the temperature 30$^{\circ} $C and the relative humidity at 40%;    Pa
(b) a cold winter day, with the temperature 5$^{\circ} $C and the relative humidity at 80%.    Pa

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

  Estimate the percent difference in the density of irona-vjb.z31yz z at STP, and when it is a solid dee3vzzb jaz. 1y-p in the Earth where the temperature is 2000$^{\circ} $C and under 5000 atm of pressure. Assume the bulk modulus (90$\times 10^9N/m^2$) and the coefficient of volume expansion do not vary with temperature and are the same as at STP.    %  ----待选择----decreaseincrease 

(a) Use the ideal gas law to show that, for an ideal gas at constant pressure8 hm,lk x),fxo, the coefficient of volume expanmx),hxolkf ,8 sion 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.