Which has more atoms: 1 kg of iron or 1 kg of aluminum? See theh0zuwu3 oa6 2kig;,ql periodic table o,uk3 ho0l6iz;aqwg u2r Appendix B.

Name several properties of materials that could be exploited to make a thermom ih8*urb1+wab aov3.set31iwosa 8 .vu*hbb+raer.

Which is larger, 1 Cb0d 5k9 : o +edof3(h3l8rwp spdaa0op $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal y,dk/p zw)r 64mvfhq,equilibrium with system B, but B is not in thermal equilyr,pk q/mwvdh)46, fzibrium with system C, what can you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to a strip6c1.kkjl 0x zp of iron. When heated, the st16 klp .jkxcz0rip will bend. 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 coe(-rqjeokt gt(ti d-(4p6q f z*fficient 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 thermostat use,ru . v99cukydd to control a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch is a glass vessel containing liquid mercury th9vku ,d cuy.9rat 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 i2 / n,1aei4(vvfqdn jfixed at the ends often have a section in the shape of a n if(,n4ivvd 1ea2j/q U. Why?

A flat, uniform cylinder of lead floats in mercury axx3-(iw* j mu5ev1oodf /hdn5wbn3j +a*t6b pt 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermome ic7t +hr;uj9vter is first placed in a hot tub of water, the mercury ini; hru+vitjc9 7tially descends a bit and then rises. Explain.

A glass container may break if one part of it is heate ndyd2,yr3h:m d or cooled more rapidly than ,hddn3rmyy: 2 adjacent parts. Explain.

The principal virtue of Pyrex gxjv1 ph5,l g31 v-kwfqlass is that its coefficient of linear expansion is much smaller than that for ordinary glass (Tablw15jk v 3fl- pxgh1qv,e 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accuf1v tm4pnj+p. rate 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 bg))* q;cxhp thadly the can will not stand up. What has happened)p q*)chtg xh;?

When a gas is rapidly compressed (say, by pushing downskx5klu +h2q1bja9p) a piston), 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 tjh+ 29p q51lubkxk )sahe moving piston.

Will the buoyant force on7:g1s ishi 8ap an aluminum sphere submerged in water increase or decrease if the temperhg1i :7ps8ai sature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s la7f gbgn1uqp (9hc q9i5w follows from kinetic theory and the relation between averagei79hbqp5fgu g9c1q(n kinetic energy and the absolute temperature.

Explain in words how Gay-Lussac’s law follows fro:0li6h,qdmxo. /ysv 4hss 0ltm kinetic theory.

As you go higher in the Earth’s atmo(j. jvmypi3i5sphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the m/c u 4bvzjsto0 52e:- sh,bkzofgs2mpw (ok8(inimum 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 the Moon’s smaller mass. Explp2jkzou2bsh5vgc, s ek 0towf/szb(: om8-(4ain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at room temperature. What j3)8 mua2p -rl4pvepdcan you infer about the molecular properties of one puvl - dr38jm 2ep)pa4relative to the other?

Explain why a hot humid day is far more uncomfort)igjjvv0of 06bq6xq1go 1 zu +able than a hot dry day at the same oiv1x0gjzu1 +j bv6fq qo)0 g6temperature.

Is it possible to boil water at room temperature (20ks i9s( xch lzy9rx 6dg .xtntr3..,b) $^{\circ} $ C) without heating it? Explain.

Consider two days when the m .m5p 2wq9s+krv hl3yn5aag0 air temperature is the same but the humidity is diffep5sg3.5a+y mk a q2 rhl9mvw0nrent. Which is more dense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerous to oi1 ebce**b)u hpen the radiator cap of an overheated automobilebeeh ucbi*)1* engine.

Why does exhaled air appear as a little white cloud in the 8rar1 u.l z;h/qo:5p ny0tg agwinter (Fig. 13–28)?

  How many atoms are there in 5sw ou.vxch2, a 3.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoiolpz35cy5 e7w (z0 cdms in a 26.5-gram gold ring compare to the number in a silver ring of the same masszop0 (3cyc5e7 li 5wdz?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this tph p--7c+q i xpqw;ieie+1( con the Celsius scale?-+pwq +i-ip t1 (;qheipc7ecx   $^{\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 tempe/u3:fpmmy zg 8ratures 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 thermo, yjzek2ccn,4 meter, the alcohol column has length 11.82 cm at 0.2n4,czck e,jy 0 $^{\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 (20xf :0 mpb)p1gg,6ixmz $^{\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 3wvtrdy o31w ,i; k+6ue00 m tall. Estimate how much its height chwrd;36iwkvt1 eu+ y o,anges 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, river45uogmfu,0dhj ts fn1 k9g98ts 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 diametnrh8 tk9fu5d1sg 4of,0jgm9 u er 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 v1b5 9smrepa -tfm6yzf,( g:ik )hw-d4 $^{\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 imj+-.wx uqh zi38*o-7vy koo2ey a a prp/d2m2n volume if it is heated from 3+mp z m8oy qihpaod7- /2.xj2uyw* raokev3-20 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350.0 mL of watru7mus8wl jx(/ lnc5/er 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 28v uuw ;zz:ly 8r+ b)zdte+8om0 $^{\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 ring ma4r+vs9 je 1*d).yzb*g les lawde 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 s 1d)yie l- 8k lt(r0o)cfbczmx v;uwr /i1t2z8o it can expand in essentially one direction only, show that the effective coefficient of lim/by2lztc10wz(c -ik f leio)t1vu rx8d8) r; near expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the densv:3wo 8dkqr7fa+b8q -wyf 2aj ity $\rho$ 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 wrj5n*jd iy10 st0cc7e idth w has coefficient of linear expansionny1et 07c 0scjr i5*jd $\alpha$ 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 isot -7- vlilhpm ow/eu7nr5a16n.czf 3da ropic solid, $\beta$ = 3$\alpha$ if the amount of expansion is small. $\beta$ and $\alpha$ are the coefficients of volume and linear expansion, respectively. [Hint: Consider a cubical solid, and neglect very small quantities. See also Problem 18 and Fig. 13–30.]

  The pendulum in a grandfather clock is made of brass9yparb2/ b36z) k 9(slddvsgb and keeps perfect time at 17 )9dkbvb /9ag ss26dy( blrz3p $^{\circ} $ C. How much time is gained or lost in a year if the clock is kept at 25 $^{\circ} $ C? (Assume the frequency dependence on length for a simple pendulum applies.)$\approx$    min(Round to the nearest integer)

  (a) The tube of a mercury thermometer has an inside diameter *einrr5 yk o s9p7e.d*of 0.140 mm. The bulb has a volume of 05 7e9e*.i*dronrk psy.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 alumin/d5y: 6tg ajflum cylindrical wheel of radius 0.41 m is rotating about its axle on frictionld:l6 5j/yg ftaess 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 blxwu9tp- ob55k 3x,p desired length when at 15°C. How much stress is required to keep it at this length if the temperature increases , wx xlo 5bt-bupkp593to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beamov3x)0 iggm -6cwng7y 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.i40ghj 0 h6kvr122 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 followiv60 3n tdc/bs1 w-jemvng temperatures on the Kelvin scale:
(a) 86$^{\circ} $ C,    K
(b) 78$^{\circ} $F,    K
(c) -100$^{\circ} $C    K
(d) 5500°C,    K
(e) -459$^{\circ} $F    K

  Absolute zero is what temperature on the Fahrenheit scale?y-tue.ypqja8r; /38s wr 9ce k ,4v3wua5zonw    $^{\circ} $ F

  Typical temperatures in q,w/c(d3qvbehk8bkc w2nz h 8tc )g/*the interior 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 en6)gagl(ga / oh1dyx 0fgine, air at atmospheric pressure and a temperature of abgy1o /6)hla(g0a gfx dout 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 im*-q,lt qbd9e*wl y1e deal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg 3garcsy:b8 ,7 3 zsv9tnrrapf6xo8 8q 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 conta7f6is 3ej- t zwi9l*zlins 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 a2z+guan ,;mez 2n *,ia zt rt2gle*(az+fad.wt 10.0$^{\circ} $C and a gauge pressure of 0.350 atm, (a) calculate the volume of the helium gas under these conditions.    $m^3$
(b) Calculate the temperature if the gas is compressed to precisely half the volume at a gauge pressure of 1.00 atm.    $^{\circ} $ C

  What is the pressure inside a 35agf6smt6hpc(n en /9/ .0-L container holding 105.0 kg of argon gas at 3859 mhgce/f n ans6p6t/( K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg of*h6 i1ww8v1 4fzisemv $O_2$ 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 buoy:/ pba+yozcfol4, ips e hmv43,fe.r.ant lift by heating the air inside the balloon, which makes it less/pso4, f oa4h mpebi+ ,zv3yc. efl.r: dense than the air outside. Suppose the volume of a balloon is 1800 $m^3$ and the required lift is 2700 N (rough estimate of the weight of the equipment and passenger). Calculate the temperature of the air inside the balloon which will produce the required lift. Assume that the outside air temperature is 0 $^{\circ} $ C and that air is an ideal gas under these conditions. What factors limit the maximum altitude attainable by this method for a given load? (Neglect variables like wind.) $\approx$    $^{\circ} $ C(Round to the nearest integer)

  A tire is filled wit6or4ksm zfh)a8,1ak .0rdq/wt6w b a fh 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 18.0 g(by fnhr*z*/ $^{\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 aa)e 9ug6*jg dind 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 oefx 6*7*ikpwkocw b b/)h8chgv,q -:k f molecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water arvj8i(bl9/ssmb 5 h)nce there in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) mof14l h v:d9awales,    $ \times10^{22 }$ moles and (b) molecules of water in all the Earth’s oceans. Assume water covers 75% of the Earth to an average depth of 3 km. $\approx$    $ \times10^{46 }$ molecules

  A cubic box of volume 5.z bc g 2s ;e ema700aia;95c(jv*urcwo1$ \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 3 sxn.v5je 31-icljnx each 2.0-L breath you inhale that were also in the last breath Galileo took. [Hint: Assume the atmosphere is about 10 km high and of cons nei 5vjl3cj1x-sxn.3tant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetis.7jxn m/(k ,td uqk4kc energy of an oxygen molecule at ST(qtk7 xund,k/skm4 j .P?    $ \times10^{-21 }$ J
(b) What is the total translational kinetic energy of 2.0 mol of $O_2$ molecules at 20 $^{\circ} $ C?   $ \times10^{3 }$ J

  Calculate the rms speedb(uuti2k*8k/l 7 ppqw of helium atoms near the surface of the Sun at a temperab7pup8i*l tq /kuw 2k(ture of about 6000 K.    m/s

  By what factor will the rms speed of gas molecules increase if the8ze 2 q;mknem .:av*vnn17bi w temperature is increasw ne8*z1iqk.ean;2 :mbnm vv7 ed 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, 4, *q 9x/zd c-a 6q km/utgty7z56m5kvg l6, -t/m gqu 6m cvz76xqkzgat559/k*dl y0, 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 20.03yyp6zwhod0- $^{\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 dv*5(o7pw.vux b uax/ constant, by what factor d5bo7 au. ( upvx/dvwx*oes $v_{rms}$ change?   

Show that the rms speed of molecx9i: o+ qvydj(wq(kp2 ules 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 mixture of two gases at the same temperature, the ratio ofsna. 4. pg(.kf7ubgy b their rms speeds is equal to the inverse ratio of the square r ugsfaybn.4p (kg. 7.boots of their molecular masses.

  What is the rms speed of nitrogen mo0u(dyl+5 o yw6qq i9kmlecules contained in an 8.5$-m^3$ volume at 2.1 atm if the total amount of nitrogen is 1300 mol?    m/s

  Calculate (a) the rms speed of an oxygen moleculebu(lorm t 5e65 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 betweenn :),xh o0) mxeadhx5z nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms spc6.( lx cq:cb7uz9hg eeed of an amino acid whose molecular mass is 89 u in a living cell atc:c q6(l.7ughx 9cezb 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;2q4 fdggat 4w of a gas can be written P = $\frac(1)(3)\rho v^2$ where $\rho$ is the density of the gas and v is the rms speed of the molecules.

  The two isotopes of uranium, gb;en+e,* 3lx io1hhh) mm.eggm(o(b $^{235}$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 pressurew:i-0, dojy guje/.wp, 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 is 9.h wgs rgwh9 wkrosdb:qv3y /( (t..l(a) . 9(.rtw :bwshg skwdv93oq/r lyh.g( 90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximat0 af :nk6zymm97pw0 )xf cv s(rur72rtely) if the humidity is 50% on a day when the temperature is u:720asr fctx6rrv 0() mz7k9 ymfwpn25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a plaj--n i4 (yns6xglk1tvce where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the 0 xxsx-(njn.*dk b1vvmountains is 0.72 atm, estimate the tempv 1.nbxs-(d v*xxk0 jnerature at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partia(grxy:kmj/d- c50b4 j l/am gyrpjk /5l pressure of water is 530 Pa and the relative humidity is (:d/rby0 yjx5 kl 4-mjpc g/m5jg/a rk40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of watv e3sg:b12)4oum ;vej:oqaoh 9gp-syer on a day when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cooker if thed- 6,:n rqlxs,dsyb v8 water is boiling at a tempev8 qd lyd ,6x-,:bssnrrature 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 vozjpku*: yn wd 5r7u/s(-rbp+ tlume 680$m^3$ at 25 $^{\circ} $ C is 80%, what mass of water can still evaporate from an open pan?    kg

  Air that is at its de0 xb-wou1; iyhw point of 5 $^{\circ} $ C is drawn into a building where it is heated to 25. What will be the relative humidity at this temperature? Assume constant pressure of 1.0 atm. Take into account the expansion of the air.    %

  Estimate the time needed for a glycine moleculew1ghp x2vpl 3. (see Table 13–4) to diffuse a distance ofv p.xlh1wg3 2p 15 $\mu m$ in water at 20$^{\circ} $ C if its concentration varies over that distance from 1 mol/$m^3$ to 0.4 mol/$m^3$ Compare this “speed” to its rms (thermal) speed. The molecular mass of glycine is about 75 u. t $\approx$    s ([color=rgba(0, 0, 0, 0.85)]Round to one decimal places) $v_{diffuse}$    $ \times10^{ -5}$ m/s
$v_{rms}$    m/s

  Oxygen diffuses from the surface of insects to the interior through 3k.k k2t9g y uymmpg/;tiny tubes called tracheae. An average trachea is about 2 mm long and has cross-sectional area ofgut y3;. 2mgkp/ykk9m $ 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 caln .fc:i9e 6bndm*.axm hb.bu4kw6+rribrated 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 9 2/cbkqd2qzcp dr /sl9 a a/5d-8w+esvr:rpdhas 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 k/9et5uu + ulzwas calibrated at normal room temperature. How much error will be made in a recipe calling for 300 mL of cool water, if the wate t9lz +uu/ku5er 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 h y2/s/)-sk.ddj hgp(qdmq f,initially 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of the original gas rem-q.)d dsd,(/h2/ pkmh qfsgyjains in the cylinder?   

  Estimate the number of air molecules in a room of length 6.5 m, widu+q.d :dontcqpb +e32th 3.1 m, and:3d 2cbn+.puqtqd oe+ height 2.5 m. Assume the temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is about ontdy6s(w/mpdhao4gn j .yi ho8*;*6 joe 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 availowih:sxq bqzzi5) 5( ,able vacuum techniques is abouqqz:w,bh 5sz 5o ()xiit $10^{-12} N/m^2$ 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 f*buzf;x(p17x rsf u58 xhf57os ;tz8n oan2s 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 tzu p(*7;nx1ofhrs8; tf z7sf5os8u af25nbx xhis advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmosphere at a speed of jeh * mcx+4*0pb2dctivpzk ,; about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this speed correspond to what temperature? (Because of this high temperature, the nose of a space vehicle must be made of szcike+v ;mp2 c tb hd*p0*x4,jpecial materials; indeed, part of it does vaporize, and this is seen as a bright blaze upon reentry.)    K

  The temperature of an ideal gas is increased c:y76jb znwwei,7v8dp t9v 1w7 qkvd 7from 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 pjm4c ze2/i/m:bhn s/770m$^2$ (a) What is the total mass of air inside the house at 20$^{\circ} $C?    kg
(b) If the temperature drops to -10$^{\circ} $C what mass of air enters or leaves the house?    kg

  From the known value of atmospheric pressure at the surfa2 f d07x9gafufo *c ubipk+g2wfi+e .t*p:sj -ce of the Earth, estimate the total num:-+ . kcjfi sx 2w g*f+au9ti7p2*fefpgou0dbber of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contained i-ot*kflxpv8;:f jrh) n 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 oxygenazf9l,aj )yo)8avu yqd-h;(s 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, measured at atmospheric pressure, iv y8s(-zo;fy aq)ljhua ,) ad9s constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl oetuc+aif8 cba7 z8 8t*f 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 gasolinepu4-jmbh 3 doa v6v6ulyc* 5)w 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 were to fit slzhc,a ;puer 4pj(5 )s)8dcwhnugly 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 jar atbgrh,b7 2 .u+) pr) jry5mduqn 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, adoptezz16:h4yif(m)ss 8 k jd :zuvbd 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, ft-( py7k9um2axm vh.:kc/ bphas 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 E 2)r7: 2:jez-yxifwhxsrbrzt-8p jr*arth is $ 1.12\times10^{4 } m/s$ so a gas molecule travelling away from Earth near the outer boundary of the Earth’s atmosphere would, at this speed, be able to escape from the Earth’s gravitational field. At what temperature is the average speed of
(a) oxygen molecules,    $ \times10^{5 }$K
(b) helium atoms equal to $ 1.12\times10^{4 } m/s$    $ \times10^{4}$K
(c) Can you see why our atmosphere contains oxygen but not helium?

  A 1.0-kg trash-can lid is suspended vdlkybv eb ;sa5y,v*p(3w2 4g 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 0v4g,(2 vsyy l;dvbbp*e5 3akw.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-di9e1x r*jtnvb/ ameter (spherical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature is constantbxv1jer9 nt/ * at 298 K, and the air behaves as a perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure in the air on the following two days: 3kkk vx 0c :ozd0xt di--1et-j 01exix-j k0dktckv dz t3o--:
(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; :vv)dn je53 pwey0s33icj3 rvyjve - STP, and when it is a solid deep in vepv35 w3v y-e js3c 0j ;r)dine3jvy:the Earth where the temperature is 2000$^{\circ} $C and under 5000 atm of pressure. Assume the bulk modulus (90$\times 10^9N/m^2$) and the coefficient of volume expansion do not vary with temperature and are the same as at STP.    %  ----待选择----decreaseincrease 

(a) Use the ideal gas law to show that, for an ideal gas at constant presr6g:l4kva ,a csure, the coefficient of volume expansion lvgak4a, cr6 :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.