Which has more atoms: 1 kg of iron or 1 kglfm d 7xfn07q; of aluminum? See the periodic table or Appendix 7 0fqxdln;mf7B.

Name several properties of materials that could be e)3 n8 w+oc )ci, gka3xpqzp0bqxploited to make a thermometewg8 o0kcp+,qnz acb3)i)3xp qr.

Which is larger, 1 C .u-jq g,g3xpj7cr 0lk $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B is not in thd 7j-up7f;a ipvd5c x6ermal equilibrium with xca5i6j df- dv;p7u p7system C, what can you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum rivm u3 cq+qw;fgn)olrf r) .73rreted to a strip of iron. When heated, the strip will wuf 3mnlco3 qrf qg));7.r+rrbend. Which metal will 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 linear e9yobxb0 )svjue g e62ndr;6p-,myr5f xpansion $\alpha$ 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 tylmk ke2 ic)6h)fna +;v+y z ze0hn.s*o control a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch is a glass vessel containing ae.h+vn zk)*)fyzksy+20ich l 6nm;eliquid 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 igc7o omwp4 . 0zw,gwd9n the shape of a mcwwwo0,dg4.o gz 97pU. Why?

A flat, uniform cylinder of l5keu9 z1sjk2qap8)jo ead 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 w gu:. kqhoy5y2r/j1 j-xr 6oldater, the mercury initialx 2 ru:jjyg.l5 /d 1-6orkhoyqly descends a bit and then rises. Explain.

A glass container may break if one part ofbm2q*dv (8c vn it is heated or cooled more rapidly than adjacent partsd 8*m2(vn cqbv. Explain.

The principal virtue of Pyrex glass ixslqn tjwuip 5u+74 y)*cr;-is that its coefficient of linear expansion is much sl;-inr jws5*u 4x+tyi)q cu7 pmaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather cloty 6eox5;jrn ub7imx/ .ecr0/ck, accurate 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 cauai.+c0 -ox d9vvyo/ tase its bottom and top to bulge so badly the can will not stand up. What has happx ytoiav/-.90voacd + ened?

When a gas is rapidly compressed (say, by pushing down a piston), i9h+d m0svt dz j2z3c n8m/m0tats temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperature using the kinetic theory, in particular nm9803ncth/2a 0+jv mszd tzdmoting what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force on an aluminum s a0o9avr5jy 2tphere submerged in water increase or decrease if the temperature is increased jy0v9a o52ratfrom 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charlj:bq;h -6( klab hyk+ies’s law follows from kinetic theory and the relation between average kineti :+ ;j(y6qbhhk iklba-c energy and the absolute temperature.

Explain in words how Gay-Lussac’s law follows fro egwe/gzz74*z aj5 q/ 1vrmam6m kinetic theory.

As you go higher in the Eaa3v: b)thic v*zm.d4mrth’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 mui7,w 9iqx7s9li9 s q +hbmqk tpy*d;2kst have to leave the Earth and never return. The escape velocity for the Moon is +i,d9m w7;bkqqsth9p kql*7xi 9 i2ys about one-fifth what it is for the Earth due to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at room temperature. What can you ind- z+9 olch3llfer about the molecular properties of one 3 -hlzld oc9l+relative to the other?

Explain why a hot humid day is far mo hxx97ywhq2z2 re uncomfortable than a hot dry day at the shx 7z y29qwxh2ame temperature.

Is it possible to boil water at room temperat 4f8f-cmxb4 ydure (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the humidity is diff1k 3+c f)k5,ksfidkq4y qa:ererent. Which is fkq:i+eskd4 kackf,)3r q15ymore dense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerous to open the radiatoao ;h lc3rr0v6r cap of an overheated automobile engine0lhr;cor63a v.

Why does exhaled air appear as a little white cloud in the winter (Fig.r6el y;q1g 4b3eir)jp 13–28)?

  How many atoms are there in a v f5w0qf5*z sj3.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare to the ah pthrwbw81o6v1v 73 number in a silver ring of the same paoww1 t816hb 3rvv h7mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this on the Ce vzzf5.;ai)b ;u8 wcizlsius scale? bcu5i) 8wazvi.z zf;;   $^{\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 tempv--gmlzz l/+s qgcln 0,ng3 5veratures 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 colu0 t3f z0vj1twmmn has length 11.82 cm at 0.0 ztj 3tf001wvm$^{\circ} $ C and length 22.85 cm at 100.0 $^{\circ} $ C. What is the temperature if the column has length
(a) 16.70 cm,    $^{\circ} $ C
(b) 20.50 cm?    $^{\circ} $ C

  A concrete highway is built of slabs 12 m long (20 zdd 9)h6f ,l27z2ejigk x+ edt$^{\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)c09dy(rqsszvx rw7qa*s--.q(x l i k built of wrought iron approximately 300 m tall. Estimate how much its height changes between July (average temperature of 25°C) and January (av x9zks.q*(lwrva) yi q7-x-0sc dsqr(erage 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 of1pg5n)kupgiy7s,0u 3xyx 7stten used and i3y 17 xxsp7gug0 5k,n uyt)spthe 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 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 . a8jop)caq) ,47o 4y nqhosyrat 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 i4cg: 9-af g-hqub3 zzl orl(yv.n zo4+jda +9ln volume if it is heata4dz.z jc+o9q-gl+b-:a3 g49z rlv onu(l fyhed from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim3dm6o4c tca-i 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 55xt- st o47ay/d.50 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 .i93 g+ki qsefplaced in a ring made of iron. At 20 $^{\circ} $ C, the diameter of the plug is 8.753 cm and that of the inside of the ring is 8.743 cm. They must both be brought to what common temperature in order to fit?    $^{\circ} $ C
(b) What if the plug were iron and the ring brass?    $^{\circ} $ C

If a fluid is contained in a long, narrow v x+n iwr.)3a,ddat 2a hvb2 wztnxo1(6lx8c1cessel so it can expand in essentially one direction only, shoowct3x,18 azc nh26rt xnwldaavx . 2b+(id1)w that the effective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the chandie4ghu11cx mgos mxr-83psy25 b,(z ge in the density $\rho$ of a substance, when the temperature changes by $\Delta$T is given by $\rho$ = -$\beta$$\rho$$\Delta$T
(b) What is the fractional change in density of a lead sphere whose temperature decreases from 25 $^{\circ} $ C to -40 $^{\circ} $ C？

A uniform rectangular plate of length l and width w has coefficient ocgtei-kh ydno ;8-fl: *n; /mlf linear expan -;f ktc: ;hynoe*m/l8dg-nli 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 isotropic solid jmdgcas;x5k pq.c12y o.a2 0w4ktml6, $\beta$ = 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 grandfat eqbu 1tru- ; uz.piv*h55y,p-mqf.ngher clock is made of brass and keeps perfect time at 17 h.f5*-iurtu5; uq -q .vpp eznbg,my1 $^{\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 th 8x i1sk0xx/p6gai5k ;gg/vzsykb 2y/ermometer has an inside diameter of 0.140 mm. The bulb has a vokx1gxgyyz2b/g iva ssk p/;/ 0ki8x65lume 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 r +6fmnyq;sw*k9 yuaa(l12 mmyotating about its axle on frictionless bearings with angular; k(ymn6a m92y f wayusl*m+q1 velocity $\omega$ = 32.8 rad/s If its temperature is now raised from 20.0 $^{\circ} $ C to 75.0 $^{\circ} $ C, what is the fractional change in $\omega$?   

  An aluminum bar has the desired length when at 15°C. How much stress is requirvr)k jg7sd (p0ed to keep it at this length if th 0g )s(rdpvk7je temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-b:2riqo3 7d,y d nw)hp)v/ w7gcatasw9eam 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.j8kpe6:8x n rk122 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 temperatures on the Kelvin scale: e1l4:t.bn3q n* os fiq
(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 Fahrenheit sca.prg0t.y c+pale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sunh gp1/j*xno:av+zu d+ 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 txupmralt2s9.- ( ycjbb2*. saemperature of aboutcs p2baaxu.rm-t.( 9jsl*y b2 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 at9tm fpjw 26 ,qvahx6(j STP using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg+3( ucf faof1t 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 18.5 kg of nit ue5s.liv *1skrogen ($N_2$)
(a) What is the volume of the tank? $\approx$   $m^3$(“Round to one decimal places)
(b) What is the pressure if an additional 15.0 kg of nitrogen is added without changing the temperature?    $ \times10^{5 }$Pa    atm

  If 18.75 mol of helium gas is at 10.bc 2ziyx vewd yfpcj *o(m( ;94f+s;6w0$^{\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 3 i+0zp(hz ydib- fh1.u5.0-L container holding 105.0 kg of argon gas at 385 .0dyi1hf puz (b-iz+hK?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg 6)+k ie *yxpfyof $O_2$ 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 thdbt/qvm007/my h .j iwe air inside the balloon, which makes it less dense than the air ou 7 twm.0v bj/hmyqd0i/tside. 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 g4c1l1gye r1k43fg -0uwwtis air at 15 $^{\circ} $ C to a gauge pressure of 220 kPa. If the tire reaches a temperature of 38 $^{\circ} $ C, what fraction of the original air must be removed if the original pressure of 220 kPa is to be maintained?    %

  If 61.5 L of oxygen at 18 4sm+vt(1 8ng:zmw ndnb,at1l.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 balll6w1+t2o lkdd. ymot)oon escapes 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 ofv4ych-;c, 7vh oqh4n5m2ufzm molecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of wate0(zdow bcq) b 6/g;kl(h sy+ihr are there in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number .ldn z 0c7,k5m/geeq oof (a) moles,    $ \times10^{22 }$ moles and (b) molecules of water in all the Earth’s oceans. Assume water covers 75% of the Earth to an average depth of 3 km. $\approx$    $ \times10^{46 }$ molecules

  A cubic box of volume 2/,e91i0ixg )hg tr/cjeilna5.1$ \times10^{ -2}m^3$ is filled with air at atmospheric pressure at 20 $^{\circ} $ C. The box is closed and heated to 180 $^{\circ} $ C. What is the net force on each side of the box?    N

  Estimate how many molecules of air are in each 2.0-L breath yowdx7p5o( yv2)xe hdt u1bqq46 u inhale that were also in the x4ex6)dpw1(dh 7oquvtb 25 q ylast 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 kinetic energy of aq.tk laz.l/ x51 (gauun oxygen molecule at STPx lql ktz u1.aagu5.(/?    $ \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 a d5-e ,g c:manpwsun -)hcr1;the Sun at a temperature of abou,rc5w u)am;s g1d ea p-hcn:n-t 6000 K.    m/s

  By what factor will the rms speed of gas molecules increase if the dh x ggu6+y+)cffho80akz7w1 temperature is increasedgx 8a wgf hyz761dkc0fh+)uo+ 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/s: 6, 2,.q(c asr jad tx n2(6h-mu+h+a 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calculate the rms spe- m ja(uanrcd2xq +t+s. h(6haed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas1i 1v++ d ggwycgfw0i3 at 20.0 $^{\circ} $ C is to be increased by 1.0%. To what temperature must it be raised?    $^{\circ} $ C

  If the pressure of a gas is doubled while its volume is held constant, by whaqr m1m,/*m uztt factor does z1/qrm* ,mt um$v_{rms}$ change?   

Show that the rms speed of molecules in a gas71wec6 sfa6 5b uffy;lur5i k- is given by $v_{rms}$ = $\sqrt{3P\\rho}$ where P is the pressure in the gas, and $\rho$ is the gas density.

Show that for a mixture of two gases 1 e2g8lgd,th)ozfk 5uat the same temperature, the ratio of their rmu12ozk,g g hldf)t8e5 s speeds is equal to the inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen molecules clah ql.4.t*y 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 om(bw:jclp g +(*5hi oxf an oxygen molecule at 0 $^{\circ} $ C    m/s
(b) determine how many times per second it would move back and forth across a 7.0-m-long room on the average, assuming it made very few collisions with other molecules.    round trips per sec

  What is the average distance between nitrogen molecu84k7mdzxge3*b :w hx fles at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms sp6 26ad2ipx );c0xws.wctniu s eed of an amino acid whose molecular mass is 89 u in a living cellpw 2xwc6 an)6;i. d t0ssc2ixu 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 writ l7k). pbe(*xbxz7odcten 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 vk z 00,.tpz1ezknc+ihlt0 wr4st) ,w55oury , $^{235}$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 rux9usd/go,pia:05o6d2 puhg jnj5n9/sp+ js 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 : ;dk.4w attw05yc3, yhu rnoqthe pressure is 0.01 atm and the temperature is (a) 9yr5ac :t ww,4tu0o .n;khd 3yq0 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew poinf/ 8xe. sbw*vlt (approximately) if the humidity is 50% on a day when the temperfvs/.8* ex wlbature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a placmt4c2z4er dz, e where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is 0.72 atm, estiyr1:h7s-at1ve u1bux 7vq :o (o uqei;mate the temperature at which water boilsq 1-t1 e1svo bo7ar(x:e:yu;uuih v7q. $\approx$ =    $^{\circ} $ C

  What is the temperatrgvk-nyq 9x r84ntz-8ure on a day when the partial pressure of water is 530 Pa and thg-tkq y-49nrr 8vxn z8e relative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a19j w(z8 tvmyc day when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cooker if the water is b+v 8/glj,t bwwoiling at a tjtw8g/ +b w,vlemperature 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 6r5- v ,uv8kkes1)kns k80$m^3$ at 25 $^{\circ} $ C is 80%, what mass of water can still evaporate from an open pan?    kg

  Air that is at its dew pointo7:eb n;re;v t of 5 $^{\circ} $ C is drawn into a building where it is heated to 25. What will be the relative humidity at this temperature? Assume constant pressure of 1.0 atm. Take into account the expansion of the air.    %

  Estimate the time needed for a glycine molecule (see Table 1i )t)p9y1ty(zd nojq.j* gk0u3–4) to diffuse a distao y)y* u k(0njdtizp1.9qjtg)nce 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 0cnk(5l:6blgn7ygmx through tiny tubes called tracheae. An a:cngm6glk(l0n 5xb7 y verage 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 bewfrvfi e07p /5e1b,ecen 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 u;z65vat tk:b1d ct g8measure 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 calib gll2)j5bj/p(xr 9+2rgl g 62mtz kakkrated at normal room temperature. How much error will be made in a recipe calling for 300 mrr2j9kx ba t g2jgg52+ll l6mz k)p/(kL 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 vaoy97jsj/ bz(xr 8w6 initially 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of the or/7y8jbv(ajos rx69z wiginal gas remains in the cylinder?   

  Estimate the number of air molecules *l5 dcmv-n 7xx6njj ;nin a room of length 6.5 m, width 3.1 m, and height 2.5 m. Assume the tem;x6vcd* ljnm jn75 -nxperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the densix rnpt kz126+8ff/hkrcs8,d qty of 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 best available vacuum techniques zyr6zg7l)z.v -qp. jdis abovyzp.jl67 gdr )zqz- .ut $10^{-12} N/m^2$ 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 pth(w7 .7tb0h28q b a-qd wuvbm below the surface, to what volume would his lungs expand if he quickly rose to the surface? Is this a dh7v .qwtw2qth bu0b7pb8(a-dvisable?    L

  A space vehicle returning fromu,x : osus w3b7upc19y the Moon enters Earth’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 temperature, the7:931xusyc uposwub, 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 idez;wmh r, ifm+k0vz.ts p1 7q0qal 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 7n 5 fuqx./em(l l+w,qzxebh3170m$^2$ (a) What is the total mass of air inside the house at 20$^{\circ} $C?    kg
(b) If the temperature drops to -10$^{\circ} $C what mass of air enters or leaves the house?    kg

  From the known value of atmospheric pressure at the surface of the Earth, ff u6:p 8d;vttk20am gestimate the total number of air molecules in the Eartgtm d6 uaf8v2 f;pkt:0h’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules c poolg0(mkd)3 ontained 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 oq )it1 hp,kk,3ru q0i 4oc:y;tyfvoj/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 rateu/ cyfo;i t:1p3,j0k yrqv4 ,oqhki)t, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in(l;zr83ez7bwy ow:j v a 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 apc )4s-24b wfcr-e vojj8 txa/t 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 E4ww/zi,j i : s2ugdl;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 ogkr*sq (n. pyp52ys f:nto a glass jar 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 tf1h+kdo- 6gyp3teki6 he 18$^{th}$ century, was a platinum bar with two very fine marks separated by what was defined to be exactly 1 m. If this standard bar was to be accurate to within $\pm1.0 \mu m$ how carefully would the trustees have needed to control the temperature? The coefficient of linear expansion for platinum is $ 9\times10^{ -6}C/^{-1}$. $\pm$ =    C$^{\circ} $

  A scuba tank, when fully charged, has a pressure of 195 atm axtr t;17k3.. xm)l oqoohbhbk )r7;wyt 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 thpmtr.h5i/xv ow6 (i f5e Earth is $ 1.12\times10^{4 } m/s$ so a gas molecule travelling away from Earth near the outer boundary of the Earth’s atmosphere would, at this speed, be able to escape from the Earth’s gravitational field. At what temperature is the average speed of
(a) oxygen molecules,    $ \times10^{5 }$K
(b) helium atoms equal to $ 1.12\times10^{4 } m/s$    $ \times10^{4}$K
(c) Can you see why our atmosphere contains oxygen but not helium?

  A 1.0-kg trash-can lid is su6a 4cbsi 0r v3w+nbotm+*41 wo:pweu mspended against gravity by tennis balls thrown vertically upward at it. How many tennis balls per second must r4 1wu et0:mv*oib3bwr na4w6cop+ m+sebound 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) bubblp tsg/bn-he5-.bp yv+b7ws)y e 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 perfect gas. How large is the bubble when it +.v ws /bh5tp y-pb7bsye-ng)reaches the surface?    cm

  Calculate the total water vapor pressure in the aig ;kyexg) 4idrziv355+w c 9ixr on the following two days: r55 w)x 4i xivdikz;c3gy9g+e
(a) a hot summer day, with the temperature 30$^{\circ} $C and the relative humidity at 40%;    Pa
(b) a cold winter day, with the temperature 5$^{\circ} $C and the relative humidity at 80%.    Pa

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

  Estimate the percent difference in the density of iron at STP, and whetltd(ka .y.jab2 t6l2n it is a solid deep in the Eak(td62lj.2ab t l a.tyrth where the temperature is 2000$^{\circ} $C and under 5000 atm of pressure. Assume the bulk modulus (90$\times 10^9N/m^2$) and the coefficient of volume expansion do not vary with temperature and are the same as at STP.    %  ----待选择----decreaseincrease 

(a) Use the ideal gas law to show that, for an ideal gas at constant presse;tp1 ov2vu68l rbw/f ure, the2wb1 tl 8vpe/6rfvu o; coefficient 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.