Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodic tablc2v k 9qil-4,ug+ grtv)kh e4fe or Appendix)l +-2hguq49 v vk,ftiker4 cg B.

Name several properties of materials that 8get8o)2qtqc could be exploited to make a thermomete8t2 coqqg)t8er.

Which is larger, 1 Clk/7 cer.ur*ngde y4( $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilib;hshg( cfq uz*;(tpj7j7a nl 4rium with system B, but B is not in thermal equilibrium with system C, what stna p j7h(jf; 47 *z(qculg;hcan you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of 5ki eiol+o7x7aluminum riveted to a strip of iron. When heated, the strip will bend. Which metal will be on the outside of the curve? [Hint5 kxo7leoii +7: 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 coeffi:py xud fp9dlu m6r*iz:u6b7*cient 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 simple h2wqv4m/tu l 6sw1zf0 thermostat used to control a furnace (or other heating or cooling system). The bimetallic strip consists of two strips ofwhq201 fu6mvw/z4s tl different metals bonded together. The electric switch is a glass vessel containing liquid mercury that conducts electricity when it can flow to touch both contact wires. Explain how this device controls the furnace and how it can be set at different temperatures.

Long steam pipes that are fixed at the ends often have a section in )doa (4,f.x0q qlh yldpl c1t+the shape of qf41(a+ .ph oqct ldxdlyl),0a U. Why?

A flat, uniform cylinder of lead floats in mercurysuju4e t o(qcvs+f(m 90*5luv 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 ooajyw3zf 6ef1f*z 6* c ,kke9nfpjc8.byln(,f water, the mercury initially desce zc1zfw.ejyy 3k*lo9(pn,f8,fa *be6njc6 fknds a bit and then rises. Explain.

A glass container may break i :5 zy11-/uoqtflt rgef one part of it is heated or cooled more rapidly than adjacentfo1/ yuqlertz:-gt51 parts. Explain.

The principal virtue of Pm6jhw pbbokb3- a *+2hyrex glass is that its coefficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance ojb+o2 mw k*36bhph-a bf Pyrex.

Will a grandfather clock, accp u0u*auowcb.k8 z, cntj84h) urate at 20 $^{\circ} $ C, run fast or slow on a hot day (30 $^{\circ} $ C)? Explain. The clock uses a pendulum supported on a long, thin brass rod.

Freezing a can of soda will cause its bottom and top to bulge so badly th 1nbg5j1m4vdkb..1r ih3g xhh e can will 1nr4ihhb3db1gmh vxg .5j 1.knot stand up. What has happened?

When a gas is rapidly compressed (say, by pushing down a pisto1kg5; sv fc;za(f 0yckn), its temperature increases. When a gas expands 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 mgk1 (z5a cc;k0ffsyv;oving piston.

Will the buoyant force on an alumhb e 5xv8w6n5xinum sphere submerged in water increase or decrease if the temperatunbe vxh6 55wx8re is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law followsj o*7r0 ishj06b)dc yi from kinetic theory and the relation between averagryjd*ch )s6 ijo0 b07ie kinetic energy and the absolute temperature.

Explain in words how Gay-Lussac’s law follows from kinetiv0v,),hb oash c theory.

As you go higher in the Earth’s atmosphere, the ratio ofv7st;sqacec:)) 5cexgc, ,.svtdcs5 $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum q4v01(0+uf ka(rrwyscpmc 1j 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 due to 4w0uv 0ayrjc( ( 1fm1cqs k+rpthe Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water a 5/kxwu kk-tac 03zblj-9f1oht room temperature. What can you infer about the molecular propertietf3 5 /lk -jwz-90hk1ocxakbus of one relative to the other?

Explain why a hot humid day ce:bhb7 aqjhxkz ,+;p2, r2ewis far more uncomfortable than a hot dry day at the se ;qj+2, axcz , 7p2hbb:kherwame temperature.

Is it possible to boil water at room temperature2 a u8kca*zypw;3 lwk2 (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperp9x3 x(o mf-sl8d1xnmf,ac4dature is the same but the humidity is different. Which is more sd84,px- xmc 1fn(ladxf 9m3odense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap of an overheated automo88,r9itt2 o * qfoxlxjbile engl*t qf io8r2ox t9xj8,ine.

Why does exhaled air appear dhlo3;9 p e ls.ar1tsl8h*id*8 n7hzias a little white cloud in the winter (Fig. 13–28)?

  How many atoms are thy5p*n; sojuda ccp,6uy8i3x ,ere in a 3.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare to the number /o( kmvg/pgcf6(mku 7 in a silver ring of the same ma7/kvc/gku og6f((mmpss?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often takey:qe ;, mxnmvrp9aoy 2)lew7 33 n6f00jxxcsin to be 68°F. What is this on the Celsius scale? qa ;2 0insnjxco3)y px3em0l79 6 vexym:r,fw   $^{\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 ankx1 g)ynnh- ov hq-y,3d lowest temperatures recorded are 136 $^{\circ} $F in the Libyan desert and -129 $^{\circ} $F in Antarctica. What are these temperatures on the Celsius scale?high =    $^{\circ} $ C
low =    $^{\circ} $ C

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

  In an alcohol-in-glass thermometer, the alcohol column has lengtg/; tzyz,ji9bvv .avwcd m;(6h 11.82 cm at 0.j;gzvwmy, / b t9(vc.zadi;v60 $^{\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 y+ esz ,kkwo-)built of slabs 12 m long (20 $^{\circ} $ C). How wide should the expansion cracks between the slabs be (at 20 $^{\circ} $ C) to prevent buckling if the range of temperature is -30 $^{\circ} $ C to +50 $^{\circ} $ C?    m

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

  The Eiffel Tower (Fig. 13–29) is built of wrought iron a +wip)dq 5x:,z 0sjmnxv(o2d jpproximately 300 m tall. Estimate how much its height changes between July (average temperature0inxs:v xdp,dm 2+)(zqo j jw5 of 25°C) and January (average temperature of 2 $^{\circ} $ C). Ignore the angles of the iron beams, and treat the tower as a vertical beam.    m

  To make a secure fit, rivets that are larger than the rivet hole are often useav2bx8x/sds 9d and the rivet is cooled (usually in dry ice) befs/ 9xv8sbadx 2ore 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 /5c ;gprc hiq;$^{\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 wooiq+:as1rmq: yv*80 / rw udfill be its change in volume if it is heated 1rq*ody r/wamv0q:fsuo +:8 i 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 100.jfsgus854drdkm9as13a 83xq -o yn0i0$^{\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 4u-mglugww xcwl(d/nhz0++ 6 mL of water at 20 $^{\circ} $ C completely fills a container to the brim. When the container and the water are heated to 60 $^{\circ} $ C, 0.35 g of water is lost. (a) What is the coefficient of volume expansion of the container?    $ \times10^{-5 }$ /$C^0$(b) What is the most likely material of the container? The density of water at 60°C is 0.98324g/ml.

  (a) A brass plug is to be placed in a rsh km4ry ;8nsca5:cd; ing made of iron. At 20 $^{\circ} $ C, the diameter of the plug is 8.753 cm and that of the inside of the ring is 8.743 cm. They must both be brought to what common temperature in order to fit?    $^{\circ} $ C
(b) What if the plug were iron and the ring brass?    $^{\circ} $ C

If a fluid is contained in a long, narrow vessel so it can4tdqn8xpr-n w 7on/t, expand in essentially one direction only, show that the effective coefficient of linear expansion is tnqn, pr48-ow/dn t 7xapproximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the den0/12x xg2x zhnszrmr :j 3fev/:uy6sqsity $\rho$ 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 bk lwa9;s8quluh/an5(. s )qzof length l and width w has coefficient of linear expansiok9(n l/ b lqqwa5) aus8sh.zu;n $\alpha$ Show that, if we neglect very small quantities, the change in area of the plate due to a temperature change $\Delta$T is $\Delta$A = 2$\alpha l w$$\Delta$T See Fig. 13–30.

Show that for an isotropic se.3h q*qi +3tw4 uh apj4gzn0tolid, $\beta$ = 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 andxiu3j:y5 wk7dx (j6h-dp (np.d(fzxn keeps perfect time at 17 :6 kj((uxpw.x7y nxnddf 5( 3idhjzp- $^{\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 mer/1k- l au.bc,mqiktla.j9qj8 cury thermometer has an inside diameter of 0.140 mm. The bulb .a,-tj19 a.k8l qbl uikqmjc/has a volume of 0.255 $cm^3$ How far will the thread of mercury move when the temperature changes from 11.5 $^{\circ} $ C to 33.0 $^{\circ} $ C? Take into account expansion of the Pyrex glass.    cm(b) Determine a formula for the length of the mercury column in terms of relevant variables. Ignore tube volume compared to bulb volume.

  A 23.4-kg solid aluminum cylindrical wheel of radius 0.41 m is rotat:yae ic4urq*+ bgf7r0t dto c6ja4l7w uk29-eing about its axle on frictionless bearings wi 6*a+9r c7w iu40q 7et2yf detgukj alb:4co-rth 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 b;u64nbd)h rf 8h* dvpat 15°C. How much stress is required to keep it at this length ir u)6n;fd*h4bvp8hbd f the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam oh3cz muro2 8ui-t tc4u09en1biu.v 7 vf 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 134.1xha9sf 8s jn ot;)n(to;,)axg22 cm at 20$^{\circ} $ C is to be enclosed by an iron band. The circular band has an inside diameter of 134.110 cm at 20$^{\circ} $ C. It is 7.4 cm wide and 0.65 cm thick.
(a) To what temperature must the band be heated so that it will fit over the barrel? $\approx$   $^{\circ} $ C(Round to the nearest integer)
(b) What will be the tension in the band when it cools to 20$^{\circ} $ C?    N

  What are the following temz6kv ulg)x- q0peratures 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 whatc qtqc(b- r05d temperature on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Ea+h3)lp l fhqc48n ,bysrth 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 temper1ea4pkr)2 iwz*v c,ogature of about 2)v1wg ro42cai ,kzep *0$^{\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 5k.5nb z5lu)5j iht loat STP using the ideal gas law.    kg/$m^3$

  A storage tank contains gs7tv.w8xao)m yy/s 921.6 kg of nitrogen ($N_2$) at an absolute pressure of 3.65 atm. What will the pressure be if the nitrogen is replaced by an equal mass of $CO_2$    atm

  A storage tank at STP contains- dol(l8m bjw73njm+j 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 t b-.3byvk1ec 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 in1pfl bov+ z vo.n/r0,rspy x9-side a 35.0-L container holding 105.0 kg of argon gas at 385 / rnyf.+l9,p ovs-r xopb 10vzK?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg oft4gy b uz7qf/) $O_2$ 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 tr9r jm. ygbg2w 8 aug(8yi8.wohe air inside the balloon, which makes it less dense than the air outside. Suppose the voim g 8g9j.oy w2.wrug8byr 8a(lume 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 ida+q2a.cp4 kerk1j+ fx 8wms ;7r+sm $^{\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.;ua cs/l.f nd:b+:8 z tsosfb*p ,ce9a0 $^{\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 g+7r2jaml h+e do/im+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 molecjcld)-0*ilhy:)ya bkbn- f o1ules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How many molec5gqr/zu9vn4k*o*g ag ules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) mole+ 36wgi4f adqcs,    $ \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 e1 lk74e,cn9vqzvu :z5.1$ \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 2.06zmnse5cdi0 wz:vo8ct7 d,e 3-L breath you inhale that were also in the last breath Galilmcve3dc5i: ont68 d,sze w7z0eo took. [Hint: Assume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translationawwtn0ovt4u3n;y j c 99l kinetic energy of an oxygen molecule at STP? 9y nu3 wct0nj v9t4w;o   $ \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 Sun7b9k0f qd la(s at a temperatufk asqb0(97ldre of about 6000 K.    m/s

  By what factor will the rms speed of g ;06bwduymx)5htozz4rv(t h ;as molecules increase if the temperature is increasbwz)o v5td;zh;ht4 y(ru6x0med 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 tl z,a4 rkk )9hnopqy2l6/a g+jhe following speeds, given in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calculate the rms speed.r o9lnzjq 46h/g klakp2ay,+) $v_{rms}$ =    km/s

  The rms speed of molecules in akb zd5:/llmz0rg0egyz)ir f 57th(s/ 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 volume5 p ndtqf4pn1l -b .9d;7ijqji is held constant, by what factb j-d.qn791tpnq d;4jpil5ifor does $v_{rms}$ change?   

Show that the rms speed of molecules.t00: p5nymlivrlxv 2) ayu( b 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 mixturll/:djv0a2)c5lt(y n9uu: gfi gw )mvgk u6q4e of two gases at the same temperature, the ratio of their rms speeds is equal to the inverse ratio ofug)lndv/ k4t ual 6j5)y:mwug(:f2cg qi0l9v the square roots of their molecular masses.

  What is the rms speed of nitrogen molecules contained in an 0u7ll.7:ojaeh4-*fbvht a yu 8.5$-m^3$ volume at 2.1 atm if the total amount of nitrogen is 1300 mol?    m/s

  Calculate (a) the rms speed of an oxygen molecule at 0o44 8;i9bhj4 sp2 7 ozvoovawpst2/cs $^{\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 dit opxs1)svd;y /md 88bstance between nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino 5o5mxa;+ *ikxt uhk4us0zn6+i: vly s acid whose molecular mass is 89 u in a living cell sxu +izvkhkyxa+o t s0um*6:li;4n55 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 pressure P of a gas can be wri vy)*7ycbjx f+pw1e z9tten 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 uranikpbb+2nfuwyx m4 84a3 um, $^{235}$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 cn/t/rk jo+w( o 2* eh3ywpd-bphases 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 aa cw78kv0-b)n;(z:)kftso bq 8inihrtm and the temperature is (a) 90 i)( rwnac0nkqi88:;7k-tfbvz) ohs b $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approq 0u ;,gfde 84d9w2x djgn;hb)gsfg7tximately) if the humidity is 50% on a day when the t dtgujeq8s2wb x9 f0g;d7n; ,) ghdgf4emperature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water 8*yru p:jdyn9boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particulwdc3ieri y.n5g7u 3 :har place in the mountains is 0.72 atm, estimate the temp 73w i.gnhuery3d5i :cerature at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on ah3-yc1+4n nhq j1 k-mziz*0j3wsn n ba day when the partial pressure of water is 530 Pa and the relati bjzqk*nj0nhiy41h w3annz3 - 1sm+-cve humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the temperaturej;.3wjmu(c*df yvh3 n3 ys3 mv is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cooker if the water is boilin:u :0k(g cyi7 g27vwuv .lplcog at a temperatc i:l72u7vwg:l .puc gko(v0yure 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 680s zp-y:rd/ u6 wiv2p(7d;d6iii lbj: h$m^3$ at 25 $^{\circ} $ C is 80%, what mass of water can still evaporate from an open pan?    kg

  Air that is at its dew point oujhsx)h hto5a9l 572hf 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 my6orzi61rgn 7 791b tgvk.hg Table 13–4) to diffuse a distance of o 6n.v1m izgrr9gbhtk6gy71715 $\mu m$ 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 t/zj k e 92z/tptl5j,klo the interior through tiny tubes called tracheae. An average trachea is about 2ez t,5lzj2p/9/jkl t k 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 cadq 6:prokqb8k6ipn4 rtd09 eoo303bj librated 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 b/q*q y85g(z w01brj(q in:n jy8shlaceen 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 cal25cupk-nkmy8 sh, x: y( 1nnzhibrated at normal room temperature. How much error will be made in a recipe calling5-1 hsky(: nn8py c2z,mk uxhn 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 gas cylinder is initirk(mai3b* 3ry y 9j(ylally 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. ykr 9bi *mjy33rya(l(What fraction of the original gas remains in the cylinder?   

  Estimate the number of air molecules in a room of lemv3pe(*,bkds5s( b oo ngth 6.5 m, width 3.1 m, and height 2.5 m. Assume the temperature is 2o35do(sb*vmb,p( k se 2$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is abouh 9c ffng2 x*6wygag,6t one atom per $cm^3$ mainly hydrogen atoms, and the temperature is about 2.7 K. Calculate the rms speed of these hydrogen atoms, and the pressure (in atmospheres).$v_{rms}$ =    m/s    $ \times10^{-22 }$ atm

  The lowest pressure attainable using the best available vacuum mg .oy6*qlsui(p06jb techniques is about 6y*b0. igpo uq(m l6sj$10^{-12} N/m^2$ 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 be.6zirv;4( daap p4 zrgwor .*(:lddbclow the surface, to what volume would his lungs expand if he quickly rose to the surface? Is this a*v.alidz(rd pzbp6wrc( :od r4;4.gadvisable?    L

  A space vehicle returpvc 8qpe0q8o1dxd3m (ning from the Moon enters Earth’s atmosphere at a speed of about 40,000 km/h Molecules (assume nitrogen) striking th mdpq d 183o(qp8cev0xe 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 at+6.e ;t4 zlsd kemn2sn ideal gas is increased 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 770mjn6h c.avrtbn)89lv8$^2$ (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 pres 6dp(2pw1ntbisure at the surface of the Earth, estimate the total number of a6di( ppb1nt 2wir molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of n 7m57ob yxtx; z;n+fulitrogen molecules 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 gauoyojrwn9-)5y *) dt page 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 con r)j9wno)-ady oyt5*pstant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liquid3 (w9zw-ystp0 sb8l)o xsw q8i 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 gasolin 6u p1f;rtuvsuit ua-hbo:2 );e 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 werejm.jhk1 y+.bj6 a8bh v to fit snugly around the Earth’s equator at 25$^{\circ} $C, but then was heated to 45$^{\circ} $C, how high above the Earth would the band be (assume equal everywhere)?    m

  A brass lid screws tightly onto a glass .x nmt0 g64cmb 16uv uvw1zyop(m8:ltjar at 20$^{\circ} $C. To help open the jar, it can be placed into a bath of hot water. After this treatment, the temperatures of the lid and the jar are both 60$^{\circ} $C. The inside diameter of the lid is 8.0 cm at 20$^{\circ} $C. Find the size of the gap (difference in radius) that develops by this procedure.    cm

  The first length standard, adopted in the 1fagqa;p4 3zx r zi35/g8$^{th}$ 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 f*tjul3pj1j wkk * nw69ully 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 ib *c6/fmq( xqpj 01zkss $ 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 suspe 9p 2(p mwr.;-te*lf bf:vntkhkn95oqz,l-fo nded 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 are thrown atme , kl9fnwtnpftolv2*kz.qp9f bo5;h -r(:- 12m/s   balls/s

  A scuba diver releases a 3.00-cm-dfb-p)m8clp 7liameter (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 behaves as a perf p m7b8cf)llp-ect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total water vapnph3qv-* qa0d or pressure in the air on the following two days: vh3 qnp0a- *dq
(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 differencs,un b,.mnrst3, 3owmj 7 yaph2 -qgf3e in the density of iron at STP, and when it is a solid deep innswq y2sumar,n,3j37bg-.o 3hp,ftm 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 const kwipk/g47iosn) ,o m3ant pressure, the coefficie,go3imn/i wopk7)4 s knt 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 dehumidify thei5sy0 4vinoe) ir cellars to prevent rot and m0io45 se in)yvildew. 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