Which has more atoms: 1 kg of irog(.mr x 2esq77 lbzn:wxh5h0kn or 1 kg of aluminum? See the periodic table or Appendix B.z7 k 72bh0mhn5 rw.lesx:(qxg

Name several properties of materials that could be exploited to make a vo svr4h7o86t thermometertorv8ho6vs 74.

Which is larger, 1 C gn;ie f(e;cxa5p+-9-o oz iv n$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibriu;3wvhv4z1 l snwo9 za0m with system B, but B is not in thermal equilibrium with system C, what can you say about the temperatures of A, B, and Cvsl 1azh ;ow 34vnz0w9?

A flat bimetallic strip consists of aluminum riveted to a strip of iron. Whe/o*dnw elrnz ;/yj) ;kn heated, the strip will bend. Which metal wile*;jy on/r/n dz wk);ll be on the outside of the curve? [Hint: See Table 13–1.] Why?

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

The units for the coefficient of li5 mxq 1;6e :pgmhmr5wgnear expansion $\alpha$ are $(C?)^{-1}$ and there is no mention of a length unit such as meters. Would the expansion coefficient change if we used feet or millimeters instead of meters? Explain.

Figure 13–27 shows a diagram of a simple thermostat used to co9 xrl l;qp(yj3ntrol 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 liqr9lp3 lxj ;(yquid 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 ends often have a section in thel;.9o5mmh7.hv ng rtk l(qin.us 9xv6 shape of x k6lg .;r7omtns5imh v9l(.vq.u h9na U. Why?

A flat, uniform cylindqvsr6 13xbvk .er of 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 placed in a hot tub of watw.x e42ju/yj der, the mercury initially desc /w4 jyxujde2.ends a bit and then rises. Explain.

A glass container may break if one part of it is heated or cooled mor3dmcg . fe9:p5 n9h1miuqg+mne rapidly than adjacent :5g+3g1demi nf9umh9n q.pcmparts. Explain.

The principal virtue of Pyrex gla9 :yasi,x3zn8 6qwvowss is that its coefficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explai 6i nz839xwos wyqv,a:n why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, acc t200b*vtwm x 7ig.bvxurate 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 causen : sa-7kj u gwgdy )zaui7vqy((4(v/i its bottom and top to bulge so badly the can will not stand uj74sdn(yiki( vu/y:(g7 -aaug )wv qzp. What has happened?

When a gas is rapidly compressed (say, by pushing down a p1y3yrib(ox (viston), its temperature increases. When a gas expand i ov31xy(ryb(s against a piston, it cools. Explain these changes in temperature using the kinetic theory, in particular noting what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force on an aluminum sphere submerged in48cw: nf: gm4e:)dxc2kzd to b water increase or decrease if the tem: f4 m)codz twgkn:x:4 2cdeb8perature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theory and the relatifa9.fjo e.dg)on between average kinetic energy and g.ffaj d9)o.ethe absolute temperature.

Explain in words how Gay-Lussac’s la(onm5x 1sjv s0ui5bb .w follows from kinetic theory.

As you go higher in th acv86 mc)l ,.(gj whi/fl.jwrbx2, sje Earth’s atmosphere, 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 h*mnt :zx*wk kx3o.* uzave to leave the Earth and never return. The escape velocity for the Moon is about one-fifth what it is for the Earth due to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere:nm3kxzu ow*.x*z tk*.

Alcohol evaporates more quickly than water at r*zqsef1/hgd*w; w7 a coom temperature. What can you infedfh;s7a*ew 1w qc*gz /r about the molecular properties of one relative to the other?

Explain why a hot hum pfu+zi585n2 d*+emzbhr abd9s r 8+egid day is far more uncomfortable than a hot dry day at the r z8+pa*zgud8bre92h d e+s mn5bi+5fsame temperature.

Is it possible to boil wategczm c/m.19baz n )tny *)t2dor at room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the sa*vt(r3 8d xdznz+c0/da u;nygme but the humidity is different. Which is more dense, the dry air or thez+gy d8n zdax( /3*ur;v0dn ct humid air at the same T? Explain.

Explain why it is dangerous to open the radiator d g1uog;+ b7mle570l0xt0hhs+ k dnmicap of an overheated automobile enginnd lmuks7l1 dgx+0hibh0; 7m0 5o+ge te.

Why does exhaled air appear as a little whitc5zvy,j 0d iu74pypk/e cloud in the winter (Fig. 13–28)?

  How many atoms are txdatgk 3o* f.6here in a 3.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atgmqa/aaq* 8.ki k0rrx.wg 38f oms in a 26.5-gram gold ring compare to the number in a silver ring of the same mass.kraxa8f*.k gq 8aqw/m3gr0 i?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often takk gzzq 8)xo28ejr3k-if a (u,aen to be 68°F. What is this on the Celsius scale?qf ,8a3g e -oijkx)2z8zu akr(   $^{\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 temperatz9o/od*g br sji, vw0/ures 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,hx-s)bo8rdc7fb k7 ,y the alcohol column has length 11.82 cm at 0.0 rb-s8c7,x)bkfh7y od $^{\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 w ,5fc xdxgi+u5 b88neof 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) o9p9f9p 2la; r)dqomg is built of wrought iron approximately 300 m tall. Estimate how much its height changes between July (average temperature of 25°C) and January (average temperature;rppml2q9 o go9 9)daf 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 5dhtsgz80y:t5 dx2ixpb2e 1 gthan the rivet hole are often used and the ri 5z8tp hdxd5sbyg 22xite 1:g0vet is cooled (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 at 4 gz v.z/ 4n,wlj$^{\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 chat1ee ykb-:6 qxnge in volume if it is heated frb:t kye1q-e x6om 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the bri:nxo22r)v ay,l x dvrumj)0inwa4( /b m 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 of wa)x*znv lzu (cs5ws+6 zter at 20 $^{\circ} $ C completely fills a container to the brim. When the container and the water are heated to 60 $^{\circ} $ C, 0.35 g of water is lost. (a) What is the coefficient of volume expansion of the container?    $ \times10^{-5 }$ /$C^0$(b) What is the most likely material of the container? The density of water at 60°C is 0.98324g/ml.

  (a) A brass plug is to be placed in a rin)kpc .e dy )f edimy1.h(i jhrgu(qh8k((/1oa g 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 irrul3d ssm9s1 l9r0gdon3o : 8n a long, narrow vessel so it can expand in essentially one directinosl:dr o3d9r1 s 0g9l sr8mu3on only, show that the effective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the d8-y1 nj /ofao6l:f: z,dh3hdu r1pvvpensity $\rho$ 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 rectangularze 1ei70 bm.ru 8a** bykw)rrd plate of length l and width w has coefficient of linear expanrbzu e e7m akir *bwr*d1.8y0)sion $\alpha$ 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 isotro p85epu;*wvc fbbm)t**dx5gdpic 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 perfect time apttv6z8 (8eff t 17 e zvf68tfpt8($^{\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+5b g huxuqnpth:(;f, c,4hx r. The bulb has :,+nx,(gh54fhqr;chbu t ux pa volume of 0.255 $cm^3$ How far will the thread of mercury move when the temperature changes from 11.5 $^{\circ} $ C to 33.0 $^{\circ} $ C? Take into account expansion of the Pyrex glass.    cm(b) Determine a formula for the length of the mercury column in terms of relevant variables. Ignore tube volume compared to bulb volume.

  A 23.4-kg solid aluminum cylindrical wheel of radius 0.41 m is rz 2hfg;ohc3 :n y--6ib6 bsjkkotating about its axle on frictionless bearings with angular velocity 3skb:hj k2;6y go- cih znf6b-$\omega$ = 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 struxf)eom.whme2-; kp+yop 5*xess is required to keep it at this length if)w umoefx*xh +opmky .- ;e5p2 the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-bbt3wt p1t2f1 l0;tcf m;dfs9 meam of 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 134.122 cm at 20 df*.)cpk0 r7cw wkro0$^{\circ} $ C is to be enclosed by an iron band. The circular band has an inside diameter of 134.110 cm at 20$^{\circ} $ C. It is 7.4 cm wide and 0.65 cm thick.
(a) To what temperature must the band be heated so that it will fit over the barrel? $\approx$   $^{\circ} $ C(Round to the nearest integer)
(b) What will be the tension in the band when it cools to 20$^{\circ} $ C?    N

  What are the following temperatures on thervv*(y1f-to n 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 temperatur x-ztjts.:nru3+ox 8oe on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun are e k. wm0+ozvj-uxa89aqc7l,babout 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 temr/2p:bh sc- eat3lp 2uperature o c2p /pl ue2rtsh-:3abf about 20$^{\circ} $C is compressed in the cylinder by a piston to $\frac{1}{9}$ of its original volume (compression ratio = 9.0). Estimate the temperature of the compressed air, assuming the pressure reaches 40 atm.    $^{\circ} $ C

  Calculate the density of oxygen at STP using the ideal gas la ci)l6tu40m rccg5(ulw.    kg/$m^3$

  A storage tank contains 21.6 kg of n1 -oa1(pstlp6*yjr u fitrogen ($N_2$) 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 contaivfmvqf)fw 0j h2)(7c xns 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 gas is at 3lk hk 3i edn):mx+wz,10.0$^{\circ} $C and a gauge pressure of 0.350 atm, (a) calculate the volume of the helium gas under these conditions.    $m^3$
(b) Calculate the temperature if the gas is compressed to precisely half the volume at a gauge pressure of 1.00 atm.    $^{\circ} $ C

  What is the pressure inside a 35.0-L container holding 105.0 kg of rvamux51g)x/ argon gas at 38gxar 5 mvu1x/)5 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg of1cra k9j3v(k yi3lwv: $O_2$ 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 insid/4 c uqsyned*2e the balloon, which makes it l 24*sqc/eun ydess 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 15 6wia7mjsstq e t 6g aq(u;rm2;zrj/ ;:$^{\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 18. btjs:f +*dbrrj(j.fiv93 7en0 $^{\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 3lte0,o k-bb/xv5m d73brz/w xrv+t(j f qs 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 4 )5c;bn0i,pnegnug v molecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How md7scm09+f0;dke*np ut*c jhs gd7r:cany molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) moch6m,snkl1 :u les,    $ \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 5.1kr/f:a fkcyoa s91+ ,2 4jxyua$ \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. 511cu hozm;hn0-L breath you inhale that were also in the last breath Galileo took. [Hint: Assume the atmosphere is about 10 km high and of c hz nmho1u1;5constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translat37c jull1 c5pmi y9msj:2h rm+ wp2c wj*/a(tbional kinetic energy of an oxygen molecule at STmjc p9*h2(7 um/spl:l acc5b2wj+mryitj13 w P?    $ \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 trp +8 1yfhn7cjxw:w 5vhe surface of the Sun at a temperature of abowcxr+8w pfyh5:7jn 1vut 6000 K.    m/s

  By what factor will the rms speed of gas molecules increase if the d1k,ha p.rl o)temperature is i.d)r1 ahk,pl oncreased 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 units of km/sl8t6 -, xu8yie.zb7 ocl -ezfr: 6, 2, 4, 6, 0, 4, 7- 8xfi8ut,-zb6l rlez eoc.y 1, 8, 5, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gasd4plppv+; 1 us 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 gababn5n c27/t5x wmk6shk yy9b29kc f1s is doubled while its volume is held constant, by what factor y2 1sn6xykktmb2bc 7k995b c f/h5anwdoes $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is gif )v 195teycpof ynr.)ven 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 f 3ci.juhd),s two gases at the same temperature, the ratio of their rms speeds is equal to the inverse ratio of the square roots of their mfdsi)u3hj .,c olecular masses.

  What is the rms speed of nitrogen m2y) - 7qgwj(cwt/e0/rbh spfyolecules contained in an 8.5$-m^3$ volume at 2.1 atm if the total amount of nitrogen is 1300 mol?    m/s

  Calculate (a) the rms speed of an odyswl 8iw )v a8--zun0xygen 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 nitrccj5 c1+nmb x1xo ad.:ogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular mass is 89 uyt;g )u8 oyy:u in a living cyg o);yu y:8utell at 37 $^{\circ} $ C.    m/s
(b) What would be the rms speed of a protein of molecular mass 50,000 u at 37 $^{\circ} $ C?    m/s

Show that the pressut)wot2k97) mzk a,r /dcdm.ture P of a gas can be written P = $\frac(1)(3)\rho v^2$ where $\rho$ is the density of the gas and v is the rms speed of the molecules.

  The two isotopes of uranium,zt+stge q, 3go ,ejj3qeu,o; + $^{235}$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 phase-v qswjn*zy k0vwws ,ha/g6; m548tzms 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 prsiui .e:bdc1p4wr 4a3j3 .kyaydw i,9essure is 0.01 atm and the temperature is (a) 90s,aw4:.j3 .bk4wur1pdi 3aicy dyie9 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximaten.39punz t9jf7+fnfh c +4zmuly) if the humidity is 50% on a day when the temf9u3.tc j+z9fpnm 74zu nfnh+perature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water bg-kar i7/ vqd,oils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is 0.72 atm,v 0op0 nr2czwl hle9)fy3+ h2f estimate thef)r0v p n2h9we023l l +hzyfco temperature at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of y- d.7e,znxauwater is 530 Pa and th, ya. u7edz-nxe relative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a daycrv/ e4+8 wnb;/,xbn axh r.dw when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cur1f fnvsi.(i:(1 llyooker if the water is boiling at a tes:.lufnr y iv1(f1li( mperature of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room of volume e91d 13dlef eg q3rf/h680$m^3$ at 25 $^{\circ} $ C is 80%, what mass of water can still evaporate from an open pan?    kg

  Air that is at its dew03h-p rdhs- 6yag0b sc point 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 gkztb n;k c- 8jjxzud ( 3i02csy;n94jdlycine molecule (see Table 13–4) to diffuse a diiuz3c8; (j ; dkjzjx2 cky90tnnsdb -4stance of 15 $\mu m$ in water at 20$^{\circ} $ C if its concentration varies over that distance from 1 mol/$m^3$ to 0.4 mol/$m^3$ Compare this “speed” to its rms (thermal) speed. The molecular mass of glycine is about 75 u. t $\approx$    s ([color=rgba(0, 0, 0, 0.85)]Round to one decimal places) $v_{diffuse}$    $ \times10^{ -5}$ m/s
$v_{rms}$    m/s

  Oxygen diffuses from the surface of insects to the interior through tiny gov/cf0por06 fd*d :qtubes called dvrpof/:6 g0cqo * f0dtracheae. An average trachea is about 2 mm long and has cross-sectional area of $ 2\times10^{-9 } m^2$ Assuming the concentration of oxygen inside is half what it is outside in the atmosphere,
(a) show that the concentration of oxygen in the air (assume 21% is oxygen) at 20$^{\circ} $ C is about 8.7 mol/$m^3$ then $\approx$    mol/$m^3$(Round to one decimal places)
(b) calculate the diffusion rate J,    $ \times10^{-11 }$ mol/s
(c) estimate the average time for a molecule to diffuse in. Assume the diffusion constant is $ 1\times10^{-5 } m^2/s$    s

  A precise steel tape measure has been calibrated at ( 3y vuy60f;pm1bmgmg20$^{\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 meaykw qk; -klci)j 3)ty(sure has been calibrated at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A Pyrex measuring cup was calibrated at normal room te864 ez k:/p xfr/ntgqsmperature. How much error wilke 4/ p8nqt f:xzs6g/rl be made in a recipe calling for 300 mL of cool water, if the water and the cup are hot, at 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in a helium gasnh r lqv,,1(8r2thwd s cylinder is initially 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of the original gas rt,r n(wdq 8h2s,lr1 hvemains in the cylinder?   

  Estimate the number of air molecules in a roomp7ig3 7(mpd(upfqd n2 of length 6.5 m, width 3.1 m, and height 2.5 m. Assume the temperat3i7pg2pfd mp u( (dnq7ure is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of s*o*h2bl 2g7l-b s7f 2kqz ocamatter is about one atom per $cm^3$ mainly hydrogen atoms, and the temperature is about 2.7 K. Calculate the rms speed of these hydrogen atoms, and the pressure (in atmospheres).$v_{rms}$ =    m/s    $ \times10^{-22 }$ atm

  The lowest pressure attainable using the best availabli8mu;h2 f i 1-qdwqx;ke vacuum techniques is aboutukfd- 2q;qmhi; x1iw8 $10^{-12} N/m^2$ At such a pressure, how many molecules are there per $cm^3$ at 0$^{\circ} $C?    $\frac{molecules}{cm^3}$

  If a scuba diver fills his lungs to full capacity of 5.5 L when 10 m below the u4a v/edq, bl0surface, to what volume would his lungs expand if he quickly rose to the surface? Is this 4evu l 0db,q/aadvisable?    L

  A space vehicle returning from the Moon enters Earth’s atmosphe p5mp1u 0i/pegk/i)n ure at a speed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this speed correspond to what temperature? (Because of this high temperature, the nose of a space vehicle must be made of special materials; indeed, part of it does vaporize, and this is seen as a bright blaze upon ree/ 0nipu p1umpi) eg/5kntry.)    K

  The temperature of an ideal gas is increased from 110d p:zxzsx -/o($^{\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 kp4e15 8bdj , jglad0y770m$^2$ (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 thez )u16wgkgr13f i5ryem -f5mu surface of the Earth, estimate the total number of air molecules in the Earth’1irf)-16uugwz 3 fm5ryke 5mg s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen m0zt 0di iv3:qxolecules contained in a 7.6$-m^3$ volume at 4.2 atm if the total amount of nitrogen is 1800 mol?    m/s

  A standard cylinder of oxygen used in a hospital has gauge pressure = 2000 psi ( d1c7m*f6v vu06k vill13,800 kPa) 6vl u76fd01iv c*mkvland at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in ac1rv jvif*hq q:vx +.4 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 iwhu,,yf kw 9oq1,x*dat 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 Eaz 3r1ifpdz h ug+d 1-p-k7w9drrth’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 at. a-x-ns-k j46e0w8 lcu vqrhm 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 rhu 0mv0sf4 +fswy 9:(rptbl21cr m6p, adopted 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 fulyw..fea)7iw d)6 ptf it5u6clly 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 Earth is rk+0e8s-wstq $ 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 agains1zz51aqj*hvg43 9hm9xoucm et gravity by tennis balls thrown vertically upward at it. How many tennis balls per second must rebound f 5zvxuc*hh9z1 eq mg 9oaj431mrom 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 (spherica f2)rn 0 0vba6qx5smk a6hybz:l) bubble of air from a depth of 2k6)vb6y banrxq0zas: f0 5 hm14.0 m in a lake. Assume the temperature is constant at 298 K, and the air behaves as a perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total 4p(idk -b23jp. d hdovwater vapor pressure in the air on the following two days: bh(od- v k.dp234dijp
(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 18rn+vvskkru y1 5b u(difference in the density of iron at STP, and when it is a solid deep in the Earth wherey+ (uv811kr r 5unbvks 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 a*l co f7uevp mnab eq58-9:0sideal gas at constant pressure, the coefficient pmel-05bua 8oqcn 97fv*:esa 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 consxaln.b v; gzhl 2d1;4vtantly dehumidify their cellars to prevent rot and mildew. If the cellar in a house (kept hnxavdv lgl4;z.1b2 ;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