Which has more atoms: 1 kg of ik2*veyeu6hh7 5(rn hy*miop8 + qca)zron or 1 kg of aluminum? See the periodic table or A5ypuy7v +e8eqm(6nh **c hoi2azkh )rppendix B.

Name several properties of materials that could be exploited to make a thermomm+m,j0j(f 2(cmp2onif p y; nlet;yl2pc,(0pj jf(i nnm+m2mo fer.

Which is larger, 1 C;bqi ,tfv2n qsc2/ls(wlse u678pf u9o g) jr2 $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B-8(s5uxe , vwdf*fetl is not in thermal equilibrium with system C, what can you say about the temperatures of A, B, anf8uw,ex-l(desf5* vtd C?

A flat bimetallic strip consists of aluminum rivem0f wnij),+fc6wh2ux g :f yd+ted to a strip of iron. When heated, the strip will bend. Which metal wil, d hxyu0ww fi6+nf)g+2m jc:fl 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 lin8n*):ys;hw wqkv houa5*j2 nsear 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 control a furnace (o0 :;qu1s3r4r)bfc tkhp9du s8h 8vdlu r other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch is a glass vessel containing liquid mercury that conducts electricity when it can flow to touch both contact wires. Explain how this device controls the furnace and how it can be set at different temperatu:;h8 4 b18ur 0sc)dp truq fuslh9kd3vres.

Long steam pipes that are fixed at the ends often have a section in theeghg, k94 afcd9t3f(xl7b mn , shape of a U. Whybl93hg 97mt fg(ca ,,dknexf 4?

A flat, uniform cylinder of leadf1m0:d of9j xz 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 placn d.am3,1wm5ox0dw qo ed in a hot tub of water, the mercury initially descends a bit and then risesom5ow.3awdq 0 d1nxm ,. Explain.

A glass container may break if one part of it is heated or cooled more rapidli*y4lt5a g tmk6k94w oy than adjacent parts6kot* 4la g5tmi49wk y. Explain.

The principal virtue of Pyrex glass is that its coeffic fmd b,8fmw3qco*;bzgdp0wvuoz), 0 2m +eh5rient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Exm)5bdr0v,w h8 bfz* 2 dp u+,qzgwmm0o ;3ofceplain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurate at /*(p. 4o7ysbccxmvxu 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 sodar+i di45yaqbi-c4r+b irg 82w will cause its bottom and top to bulge so badly the can will n +rd iw 48bciir2b5i-qgr4y+aot stand up. What has happened?

When a gas is rapidly compressed (say, by pushing down u)+d m c9 kaabz0u3p9va piston), its temperature increases. When a gas expands against a piston, it coolsdcb 09+ uuzvpk9m a3)a. 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 sphefb 90-wzrwui(4d l0 wrre submerged in water increase or decrease i9dr0-w4l u0 f wbrz(iwf the temperature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kineo 61 rlvbcnnw3utu4( ;r342kcri 4cjdtic theory and the relation between average kinetic energy and the abso otnju4i;ur4knblc 6 d43w (21vrc3crlute temperature.

Explain in words how Gay-Lussacb;..kyn qg z8xj q/3ay’s law follows from kinetic theory.

As you go higher in the Earth’s atmosphere, the ratio / 5l/dodf:uow of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum xjp2lndu1y 3n (3c fymzu5 8,aspeed 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 the Moon’s smaller mass. Explain why the Moon has practically no z3famynn (y 3pu2d1xjulc,58 atmosphere.

Alcohol evaporates more quickly than water at room temperab0ifl. 9 s.rr. nkeoj6ture. What can you infer about the molecular properties of one relative tof.r skjo0nirb.96.el the other?

Explain why a hot humid day is far more uncomfortable than a hot dry ftqv :49f;q,q:jnaoo6 e zi hqw,/)od(hfd/wday at the same tv oq dzifnw/,qhf/,(t6q4)f;w9e:od :hj a oq emperature.

Is it possible to boil water at room temperatureyk.7w,v*rgnjku(bkjgf6y1ym bebxv ( 0;: 3y (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperatu+*1pck*y wvi q; xbc143 uyojdre is the same but the humidity is different. Which is mov3iwycb c pxkqdo*j*1 ; y1+4ure dense, 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 automobma(uu-/6k - v yrmi3tnilen/6k3tirua - ym(vu-m engine.

Why does exhaled air appear/yso/0 h6u,n p 8;kdl)injnjp as a little white cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4rd9;1b:h0p.oj e8gqat, skmh -gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring cmq vyg3z 97ej x( l3lpddr83z8ompare to the number in a silver ringp93l87r ldy x3q8jv m3g( ezzd of the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is tdq hcos 67co n:d m8,n(mt/8fnbb. p;mhis on the Celsius scale?b6q. ms o7 dc m/hptfn,;dn:8m(co b8n   $^{\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 temperatu pa7om1+dm:l nres 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 lengtwo0pik/q r 9oi3 y 0+j*x,rtq/ns5bhbh 11.82 cm at 0.+tixh 3r j*b0s9nbpo y/ /wirkq,05qo0 $^{\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 sn 9s,-qpjd: uilabs 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 approximately 300 m tall5mrv 9vdjem,dcv8gn (v+,w 8j. Estimate how much its h5vrecd89j,mwv(mvj8 n , dvg+eight changes between July (average temperature of 25°C) and January (average temperature of 2 $^{\circ} $ C). Ignore the angles of the iron beams, and treat the tower as a vertical beam.    m

  To make a secure fit, rive pp e b 6co.44-nk.llba/nqgu zmas/36ts that are larger than the rivet hole are often used and the rivet 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 diametemaa3lzoe4s4cp-. pn q.bgk/n u 6/6lbr 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,5:ik)ov9ud 8mn pxw i at 4 $^{\circ} $ C is $ 1\times10^{3 }kg/m^3$ What is water’s density at 94 $^{\circ} $ C?    kg/$m^3$

  A quartz sphere is 8.75 cm in diameter. What will be its change in volume if it4 v,fdp *u(un sp t.aj2t0*mtg is hea,t(p2tvd g. 4ja p*utu0f*nmsted 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 ql:8 v( zkhl 1brwrg7 ios.w5(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 water at 20q-l;1 v7ytcsh2s1w jb $^{\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 rggvgr5d .a/h* drd b5: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 lo17all*yre4 keng, narrow vessel so it can expand in essentially one direction only, show that the effective coefficient of linear expansion ae e l7r1y4l*kis approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in thbf 5v:t z*qdo3tjzj)g ;wd1 ,ce 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 width w has coefficient of linear, 9zjc8ytexv m8tai-; exictvj -y me;a8,9z8txpansion $\alpha$ 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 solid,pix 7ouc/ m0a86+ tzcw $\beta$ = 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 mxoxtebk9f*hn02( g :f ade of brass and keeps perfect time at 17 o n*tx0xfe2fg:9 b hk($^{\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 4o-:ag hnfsa ,(mt,u m9ud2amhas an inside diameter of 0.140 mm. The bulb ha s,a2adnm g fm-hm:u49,(ato us 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 whee,r 4ymgoc. ,ardg1p6 yl of radius 0.41 m is rotating about its axle on fp.yr,mocy4r dg g16 ,arictionless 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 sdf xi:0xs) gz8tress is required to keep it at this length if the f:ig)x z0 8dsxtemperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of 7rf; *o.pg z6t ;e1gwk3ks kfucross-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:s( ,t uqmsijfx8/u;v $^{\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 the Kelvin sp86j i dkt 2z) ;;1lfu2teokljcale:
(a) 86$^{\circ} $ C,    K
(b) 78$^{\circ} $F,    K
(c) -100$^{\circ} $C    K
(d) 5500°C,    K
(e) -459$^{\circ} $F    K

  Absolute zero is what temperature on the Fahreki+k xrte:jf1k,9t e yi3h3o 2nheit scale?    $^{\circ} $ F

  Typical temperatures in the interio ib /n(sr)/h (,rw v0jzurjhlkzn3r9 ,r of the Earth 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 temda,- cu5u83 o72qd,qz dvhkvtperature of a3c k, 8tvo-ud2uv7q d zqdh,5about 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 ga:ilo.h lt *ix3s law.    kg/$m^3$

  A storage tank contains 2uj3j.s1(ny4b urxk7 i ksn5e:1.6 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 containsp6kfwl jzu48c6kx/9 +g vp i*g 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 1d1t3ia kb913*oxzft wpi6 o3p 0.0$^{\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 v0v zmqhd 4hh r(2rnxz4-d:1t holding 105.0 kg of argon gas at 385-zt 4h 42dznx0h1qvmrr (hvd: K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg ofwb4i63z*vx , qvoapqt+vw7b 9 $O_2$ 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 heatin mr w2lfz83t/e4 koth) p4gt)rg the air inside the balloon, which makes it less densh2 gztopmw/43k t4 tr)l)er f8e 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 airc u 2kr6l*7aic 3dhbs: 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 aoxdbc+yg lb a)v.0t/od-jb.l :8ex: ut 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 20 ,rc as0m,1 iu/hkg5js.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 molv y3(mx rfws piqk- j61/u3t0cecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water arep a:keyl5 ind0p2 ,6e:eku h2s there in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (aa x21:2c5zcq e9 h9h lwmdwup;) moles,    $ \times10^{22 }$ moles and (b) molecules of water in all the Earth’s oceans. Assume water covers 75% of the Earth to an average depth of 3 km. $\approx$    $ \times10^{46 }$ molecules

  A cubic box of volume omko52eb ,asi( kwp 6kyx,-5f5.1$ \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 hsf0p(1vh gpmiy/3l tyb6 +6j-L breath you inhale that werehsg+yfv6y( / jbt10m6lihpp 3 also in the last breath Galileo took. [Hint: Assume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational ki5.myofpoe8: qnetic energy of an oxygen molecule at STP.f5 omp ye:8oq?    $ \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 oyitdzc , l+v8z,.pd(qw6,o p(5p agdmf helium atoms near the surface of the Sun at a temperatum (d 5(t68,c+ y zop vlw,pag,d.qzdipre of about 6000 K.    m/s

  By what factor will the rms speed ouu,y-bp8l67elg57ti igba6 a f gas molecules increase if the temperature is increas-a6 7 5yugbiaei7b p,gt ll86ued 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, gts9.z*zu ru lo5h run7s 9wd+-iven in units of km/s: 6, 2, 4, 6, 0utn*-sl+rus9 . zz udwrh79o5, 4, 1, 8, 5, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at 2n,y;:jh fv rk(0.0 $^{\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 c)qesj*e 5a6 lis held constant, by what factor does 5ecq a6sl*e j)$v_{rms}$ change?   

Show that the rms speed of molecules in a gas is given by ivonxox s codc:7v87rk))0 *n $v_{rms}$ = $\sqrt{3P\\rho}$ where P is the pressure in the gas, and $\rho$ is the gas density.

Show that for a mixture of two gases vqx9+2 j:t * vk7iov7a aatms+at the same temperature, the ratio of their r2vv9v:7 xjqkmsa+oi t a+ta7* ms speeds is equal to the inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitro n3kpfxkd*t i-+yb0+/:lhol6dk e2tw gen 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 rmp ibu:ubx+p;x+m f6u:s 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 nitrogens6hx3rraam.n :g o56e568w-jjh z imb molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecckejk;*qz: j* ular mass is 89 u in a living:*;jqz k*ckje cell 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 written P61ak7sosp /8mda sdy;ju+;c c = $\frac(1)(3)\rho v^2$ where $\rho$ is the density of the gas and v is the rms speed of the molecules.

  The two isotopes of uraniu (k34 v+bhjjxn9hypx -m, $^{235}$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 pressureslq mr *j0qb .(hu2a-t, in what phases 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 temperature isi1 qv*9gn tr1d (a) 9g1r q*dn1itv90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximatelyi1x7l p s2yf4f) if the humidity is 50% on a day when the temperature is 25 1yi2 4ffls7p x$^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure a w5pkym7k 3+/o6u2cdl gutm)mt a place where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is 0.72 atml7i.pf:) zk gw, estimate the temperature at which water bpgkzl7.i ) fw:oils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a 7iuno* wv/, yb)y3 ejrday when the partial pressure of water is 530 Pa and the relative humiv, ro be7ny*)j 3uyw/idity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the temperature i(7-3o )zndihy )plrd()yxqdo s 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressxva*r x/ ,enp0ure cooker if the water is boiling axn0x a,e vp*/rt a temperature 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 6gyuw,vj)v 01 o80$m^3$ 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 of 5 vhf+:-l;;2 jiwjphydlv0x 0b $^{\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+atx z2h6acrinfsy15m2g r,7) to diffuse a distance5ryf ci+hm2 ,x 62g1nzt7sra a 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 insec.a)yh0ykcq 1/ zv;*-g kixwmgts to the interior through tiny tubes called tracheae. An average trachea is about 2 mm long and;.qim10w/ aky *g yx)kcg-v hz 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 bw ms.s5ydym6 ul(h6b ;r0p,t ween 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 calibratz s,c+ik:,da sde63kbj im3/ted 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 n .awmjy3 ci3tsnb y(z5)7t)7(bj kulat normal room temperature. How much error wil yt kjblt53a n(jsmy)b.(i 3)c uz77wnl 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 gas cylinder is initially 28 awaza*g)z: m7zv6mb n- tm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of the original gas remains in the cylind a*zbwvgn7mzz-6:a )m er?   

  Estimate the number of air molecules in a room of length 6 rl7 zejpnd/qf.590tf.5 m, width 3.1 m, and height 2.5 m. Assume the td 7ln/9t pfzqf5r.0 ejemperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density ocny -pdt7--dmp psa:m -jc *r)f matter 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 best6q. t89lzher zt mv-h* available vacuum techniques is abouqzh9-lz e6h .t8rm* vtt $10^{-12} N/m^2$ 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 tosggx;)zc+,md hj w4t cf6n// g full capacity of 5.5 L when 10 m below the surface, to what volume would his lungs expand if he quickly rose to the surface? Is this advisablejnf/+)g czshg,6 m;4gwdtxc/?    L

  A space vehicle returning from the Moon enters Ea+kv w,*rh ex-arth’s atmosphere at a speed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this speed correspond to what temperature? (Because of this high temperatua-xwrh v k,*e+re, the nose of a space vehicle must be made of special materials; indeed, part of it does vaporize, and this is seen as a bright blaze upon reentry.)    K

  The temperature of an ideal oq (j*a/b f.oj7a c93j4mfvdngas 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 7 -q6m6 lntr oe43so*bt70m$^2$ (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 atmoss4ard x+ 1qe jn//.wly8,u nigpheric pressure at the surface of the Earth, estimate the total number of air molecules in the Earth’s4 xw1nga.8+/ yd/ire,sljuq n atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contained in z:odpn)k0;hg 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 offw )+7qcsu6o xygen used in a hospital has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, mea)ffu o76w+c qssured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of lipqcgn o4w1m,- quid 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 at 0dxe 11/x2q2wvm i uo2h$^{\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 11)zjlfekw r3Earth’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 6chs )suaeb ou,98bi3;jem4q-g i r*rat 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, adopt yez,-v4m 90:mul v:f lsd k5-vhgtvw -en);kxed 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 press6sr15cm-/r1hapvy0o 3uhz+ fvy celc +t8 +ybure 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 isr)yiz p jgn2g17k1hd8 $ 1.12\times10^{4 } m/s$ so a gas molecule travelling away from Earth near the outer boundary of the Earth’s atmosphere would, at this speed, be able to escape from the Earth’s gravitational field. At what temperature is the average speed of
(a) oxygen molecules,    $ \times10^{5 }$K
(b) helium atoms equal to $ 1.12\times10^{4 } m/s$    $ \times10^{4}$K
(c) Can you see why our atmosphere contains oxygen but not helium?

  A 1.0-kg trash-can lid is suspended against gravity by tennis balls thrown v53tyhl s/h (vbq1jv g7ertically upward at it. How many tennis balls per second must rey5vh jsgv (h7q/t13lb bound from the lid elastically, assuming they have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter (spherical) b6xihu6ywanu-jzld14t*(, hl ubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 Kd-ux u6*tw (,n h4j6 yliza1hl, and the air behaves as a perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure ob z0biy) 0l/v qjyr(jq/q3p.in the air on the following two days: jvi )q plb03q 0royz.y(/q bj/
(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 differenceqr)uf)gn i7zbk; *0qj in the density of iron at STP, and when it is a solid deep in the Earth wherengrk* zif) jq)07;bqu 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 yklhym+i/ *n 5an ideal gas at constant pressure, the coeffici5k/yhlin y*m +ent 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 pi xr2n4,p6by( (khrk constantly dehumidify their cellars to prevent rot and mii yx nhkp( (kbp24r,r6ldew. 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