Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodic table gkx+jgcgs-hm/wx a7c4- ox* 6hx;2t kor Appenoa xhk-hckxgx7xws- +2t mc g4j6/g*;dix B.

Name several properties of materials that could be b,fl yj.9q*uv a*: illexploited to make a thermometer.l,v**l :fabl9q.ju yi

Which is larger, 1 C nm5xnr x),3ak hbvl)adq4*w-$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with syst(2jlgja/xmz 3v 8f bzz1 m;2rlem B, but B is not in thermal equilibrium with system C,gmz zrj 21vx/f8m 3;2j zlb(la what can you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to c6r,mkq -bj.h a strip of iron. When heated, the strip will bend. Which metal will be on the outside of the cur . 6khbjcm-q,rve? [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-s(lb p;.;hke9om/ mjqos2wm 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 ofg x ,p4)pjpj.y a simple thermostat used 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 that conducts electricity when it can flow to touch both contaj g,4yjpp.) xpct wires. Explain how this device controls the furnace and how it can be set at different temperatures.

Long steam pipes that are fixed at the ends often have a section in the shaxbfva3-h w 8dyh.+) -vs h ps/jhc39pepe ofpb3 cx +3hfvj9d.-s he-)8hyphwav /s a U. Why?

A flat, uniform cylinder of lead floats in mercu (01l (cg5/hly s:qgekcay ,hery 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 water,m5zza* (kzd t0 the mercury initially descez( mdk zz*05atnds a bit and then rises. Explain.

A glass container may break if one part of it is heated or cooled more rapi) vf yud6f1x4vdly than adj f4uxyvvfd6)1acent parts. Explain.

The principal virtue krjw,(3hq 1lfv1ie 3z of Pyrex glass is that its coefficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives r qk,ij r1(helwfz1 33vise to the increased heat resistance of Pyrex.

Will a grandfather clock, accura5 lvp+jzdo.3;bnptb7 te 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 bva j0xu39oy *pnjnl(bjnd t x0,/ )2obottom and top to bulge so badly the can will not stand up. What2n ,)93 ajoynpn0t b(0jlvjx *u/xb do has happened?

When a gas is rapidly compressed (say, by pc548ugam b+mbp+, pf lushing down a piston), its temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperature+l,bu+ gb c5f8amm 4pp using the kinetic theory, in particular noting what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force oj o ;0sre*ni nre*k3c o;2y1aen an aluminum sphere submerged in water increase or decrease if j ; ner; e2oao*n13s0k* cyreithe temperature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charl9pjvt ka z+i3*.f qv+qes’s law follows from kinetic theory and the relation ftaq v+ij.vzpq9*k +3between average kinetic energy and the absolute temperature.

Explain in words how Gaxi;*o-n*l:1 8lubjb 5oyedpk y-Lussac’s law follows from kinetic theory.

As you go higher in the Earth’s atmosphere, the rat+ bt,efda ce3;y xaz)*w(4rcv.ndao.io of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum ua,v(k,m gmbiv+i 9r w8w6dfmf08zp2 g.ixt/ speed an object must have to leave the Earth and never return. The esca2 ./kg8tridaf m9i , wb p(,vi+m8wmgv0 u6fzxpe velocity for the Moon is about one-fifth what it is for the Earth due to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water atw1r95qp8t+uv 7 p7xqixy4e jt room temperature. What can you infer about the molecular properties w5tqr8i y +x4q9 7 1tvxuejp7pof one relative to the other?

Explain why a hot humid day isj :9 mtuq,wg(g6;jtas far more uncomfortable than a hot dry day at the same ts mug 9(a,w ;j6qtg:jtemperature.

Is it possible to boilcvjs6b6* s jm42qbq;l water at room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the a ay6fz9gh:2dh ir temperature is the same but the humidity is different. Which is more dense, the dry air or the humid air at the dhh2 f96zyg :asame T? Explain.

Explain why it is dangerous to open the radiator cap of an overheated asv2 v)aoxq 7(wd78j rzelmq nh vj+89;utomobile engin)7z9dl28j7se8v;rm+oqqwx jav( hn ve.

Why does exhaled air appear as a little white cloufm.qflp: 9g 3cnm1te0d in the winter (Fig. 13–28)?

  How many atoms are there in aah w:p jd4;djz ,uug0c7,9 emz 3.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare to the .tpae1n3og *rnumber in a silver ringopte 3 g.*ran1 of the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken:5*-uw x5wwl gs zw2ao:a;uyg to be 68°F. What is this on the Celsius scale?-5yw 2w:* aw:g5a ;zuousglwx   $^{\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 lowes t0lh-x0ym q;ht temperatures recorded are 136 $^{\circ} $F in the Libyan desert and -129 $^{\circ} $F in Antarctica. What are these temperatures on the Celsius scale?high =    $^{\circ} $ C
low =    $^{\circ} $ C

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

  In an alcohol-in-glass thermometer, the alcohol column has length 11.82 cm a/rou;uik 2+q at 0.+/ri2aouq u;k 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 buidhlyn-1q5 m:b40z ymf lt of slabs 12 m long (20 $^{\circ} $ C). How wide should the expansion cracks between the slabs be (at 20 $^{\circ} $ C) to prevent buckling if the range of temperature is -30 $^{\circ} $ C to +50 $^{\circ} $ C?    m

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

  The Eiffel Tower (Fig. 137pjr r 6)1i7jdgyhe gf/p* h9u–29) is built of wrought iron approximately 300 m tall. Estimate how much its height changes between July (average temperature 1jup)/hrf7 9 g*e yjdiphg76rof 25°C) and January (average temperature of 2 $^{\circ} $ C). Ignore the angles of the iron beams, and treat the tower as a vertical beam.    m

  To make a secure fit, rivets that are larger than thf) h0id s 5(tc:rly+.uvg9n;- hw2a w(utmst ze rivet hole are often used and the rivet is cooled (; :vum0z+c s(f.yhg)dw ni tua5s(2whttl9-rusually 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 45 zvi 7qjj8q ve3z,grat 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 ic k5-clfe7aa 2x7lh4mf it is mkc7e a 7acl24x-5fhlheated 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 water60ni uq56cl+c,e tksj 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 55fk8-h7 0/jc s7nchq iq.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 placed in a ring made of iron. At 20 tviu; lje4iu l/wu;8x5/la 5o$^{\circ} $ C, the diameter of the plug is 8.753 cm and that of the inside of the ring is 8.743 cm. They must both be brought to what common temperature in order to fit?    $^{\circ} $ C
(b) What if the plug were iron and the ring brass?    $^{\circ} $ C

If a fluid is contained in a long, narrow vessel so it can expand in essa)gn fq ub-o3q(+wx05n/ 7xrvxw+cu zentially one direction only, show t-q w bc + )qnu7(rfxz/gan503wxxv+o uhat the effective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in t ) vr qr4zbr 2yowrcbs788b0o7he 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 p .ppbxyf jz;+)late of length l and width w has coefficient of linear expp;)+ zfx.pbjyansion $\alpha$ 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 isotropic7uu s v0)ta-r6n4tzqm solid, $\beta$ = 3$\alpha$ if the amount of expansion is small. $\beta$ and $\alpha$ are the coefficients of volume and linear expansion, respectively. [Hint: Consider a cubical solid, and neglect very small quantities. See also Problem 18 and Fig. 13–30.]

  The pendulum in a grandfather clock is made of brass and keeps pe3sfzj- l,omxp50rts; rfect time at 17t,p0m5jlz ; 3x o-rfss $^{\circ} $ C. How much time is gained or lost in a year if the clock is kept at 25 $^{\circ} $ C? (Assume the frequency dependence on length for a simple pendulum applies.)$\approx$    min(Round to the nearest integer)

  (a) The tube of a mercury thermometer has an inside diameter of 0.140 mm. The bpupxov , .do.5ulb has a volume ud. ov px,o5.pof 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 rotatin dsr1z2z2. a0duf /as)e37k puajarp6g about its axle on frictionless bearing)dkp z7a jes0arp2sruzf d26/.a3u1 as 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 atev1 f; rddm;c u su126sn1r5p(, szonf 15°C. How much stress is required to keep it at this length if so2ceup1rvz s611uf( mrs , nd;;nd 5fthe temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-sec5 n1+o3;b efgrgny 9qn6tj:d5l 2 qgxwtional 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 ac jmx;bqer// +m. ,ksyt 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 temperaturpk)vb5.ia44qim,x3 .w wif6 pc/ vqzta j6+wmes 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 scalem)k bx x7h, vu40gy4lb?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sunds46a v( -d +2nj:3bwr dyhmkn 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 atmosphe9 j.:+e0on gjv ror:oaric pressure and a temperature o:. 9:anjojgeov 0r+ rof about 20$^{\circ} $C is compressed in the cylinder by a piston to $\frac{1}{9}$ of its original volume (compression ratio = 9.0). Estimate the temperature of the compressed air, assuming the pressure reaches 40 atm.    $^{\circ} $ C

  Calculate the densit5aew82;csj k*t f5qf az) 6ixly of oxygen at STP using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg,0fr z ige 3c/ 9ip0id+5;jydghnyu(e 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 +piy4pl .xj 8.e hs/ke18.5 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 1wvw:; 08q, jrgpnbd 9k0.0$^{\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 hole+m7q q9tgi9g lte s1*ding 105.0 kg of argon gas at qeimg l1 +*sqe7tt9g9 385 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg lk.k4z6k x mc9of $O_2$ 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 mf ynbe g9 xgp2mcs+m8;c+8 2 vg7hav(its buoyant lift by heating the air inside the balloon, which makes;m+yp2m(avc+9gegg8c8vn7x2hf m s b it less dense than the air outside. Suppose the volume of a balloon is 1800 $m^3$ and the required lift is 2700 N (rough estimate of the weight of the equipment and passenger). Calculate the temperature of the air inside the balloon which will produce the required lift. Assume that the outside air temperature is 0 $^{\circ} $ C and that air is an ideal gas under these conditions. What factors limit the maximum altitude attainable by this method for a given load? (Neglect variables like wind.) $\approx$    $^{\circ} $ C(Round to the nearest integer)

  A tire is filled with ain xn l.q6n2ou8r 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 *. u8brhs9 c3)wdgmcj18.0 $^{\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 ha, lqpqxw)mj0)e 9j(oo nd at sea level and 20.0 $^{\circ} $ C. When it reaches an altitude of 3000 m, where the temperature is 5.0 $^{\circ} $ C and the pressure is only 0.70 atm, how will its volume compare to that at sea level?    times the original volume

  Calculate the number of molecules /ic5c93+es+lox, x bwl $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How many molecb3nq6xemtek z 6wzsg6t, t8th6 41si2ules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) moles, jzifns6m slpr n4p(ro0)0:k,    $ \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 5.1 89q 8jf1zezqs$ \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 you inhale that werhqxkxm / mg ern9*m+*-e also in the last breath Galileo took. q x*-rk/nmh mmg 9*+ex[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 an oxygen molks vl4)(h esb7ecule at STP?e)ssvhk47lb (    $ \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 ati2 o0c.k. cduvoms near the surface of the Sun at a temperature of aboucdok0 u cv.i.2t 6000 K.    m/s

  By what factor will the rms speed of gas molecules increase if the temperaturqq2+1h0p tjkt) 6dm tze is incretmz+jk)pd 2q 10ht6qt ased 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 fo pvq ):5voz-w2ew lg:dllowing speeds, given in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calculatvvq:-gdle:2wo5 p z)we the rms speed. $v_{rms}$ =    km/s

  The rms speed of molejwjda+xn9n-g* xygd.k5*k1q 2 tzx n 8cules in a gas at 20.0 $^{\circ} $ C is to be increased by 1.0%. To what temperature must it be raised?    $^{\circ} $ C

  If the pressure of a gas is doubled while its volume is held constantgy, yx97h,1t7pe. jvfd /y wzy, by what factor doezv/yt.7egx,jyd 9hyw1 fpy 7 ,s $v_{rms}$ change?   

Show that the rms speed of xubakr*m;+4xomg3 3 co:i,mj molecules 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 temperaturm jmrl/4az 0a+f0m ,gge, the ratio of their rms speeds is equal to the inverse ratio of the squamjz/ rm f0ag,+gl04a mre roots of their molecular masses.

  What is the rms speed of nitrogen molecules contained in an 8mkx6o1f(uao e)uxbi+2f j*u-q b* s.v.5$-m^3$ volume at 2.1 atm if the total amount of nitrogen is 1300 mol?    m/s

  Calculate (a) the rms speed oba8:0(*/ elwtdr3dzkf j a:gsf 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 molecules at STP uraedav6w i5dz/* 60p?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino lg6 pn *o51i-q9ecdp .seygi/ acid whose molecular mass is 89 u in a livinge59 pdoieg*yi / g-1 pc.qlsn6 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 b;uibp0hy )gj(p 7nb 0r)d gey,e 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 u z8rd4s*4ovcqqm rgqkx n3kow),gx*u) g(i ;1ranium, $^{235}$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 whx)r: o4ms so9jat 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 4m*pd 0hknxwi9t1b) o0.01 atm and the temperature is (a) wi h9 d4n1tk)* bm0pxo90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity is 50% on a day when* svel5y1ha 2xq ::dky the temperature is vs:dh512 alx yqe:k*y25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air preskn-j k67ovdwzjp,hqs(/ l) b ;sure at 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 at;;+s e38.b8 kldey n quwb-6 qcelq.sbm, estimate the te ks le;8 w.b+ed-qb 6ceu.y;bqs38q lnmperature at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a5p 15ib lfy:ckq ducy 77j5yt1 day when the partial pressure of water is 530 Pa and the rel dp5c k jqy5yulbt 757c1ify1:ative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day bpux-8p: x1sl when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cooker ifq8r.9 he,t b psin 2ajpj.08;4w2lg a gwrjn1e the water is boiling at a.,p;tnreiebjqg22 rg.ajpalh sj w80 1w 98n4 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 vw ji*2kh3 jdr7jh7ibsky.9 b+oc64 jg olume 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 dew point o ab0g6tmf zn,+f 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 gly grpafr8b..e.k*.d2: , n d wbii3hehmcine molecule (see Table 13–4) to diffuse a distance of 153dwi fn ,mr.r..8h bbdae: 2ie*kpgh . $\mu m$ 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( g7pwe 8cled)4z +q(7hqci yvts to the interior through tiny tubes called tracheae. An average trachea is about ly ec(i4 qh)zg(qc vd 7e7w+p82 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 measuko9-l ,3 wwjay rb.0wtz ev63dre 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 precise steel tape me6.ll .mmjbs:d;9s *meits 1cw asure has been calibrated at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A Pyrex measuring cup was calibrated at nouis5/49.g)t cbi6qqnru : bw- v)xtznrmal room temperature. How much error will be made in a recipe calling for 300 mL of cool water, if th 6 zt. )uc)wig/nr n:4 i5vqstbqxb-u9e 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 atm.:j owxh 4:4fwn-p9jen After many balloons have been blown up, the gauge pressure has denhjwjxo 4::-wfnp9e 4creased to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air molecules in a room of length 6.5v -z0;qmlal1s m, width 3.1 m, and height 2.5 m. Assume the temperature il-q0vs1zm ;la s 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the denchv fkl74 57yc8,ev aj(l2rj (rpk7qnsity 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 6wrts/, vfk (qvacuum techniques is about w st(6vrkf,q/ $10^{-12} N/m^2$ At such a pressure, how many molecules are there per $cm^3$ at 0$^{\circ} $C?    $\frac{molecules}{cm^3}$

  If a scuba diver fills his lungs to full capacity of 5.5 L when 10 m below the sqkrdy 9 ;;2b2;:/bdzccqui/o u+- i l u:krpqjurface, to what volume would his lungs expand iql;:i/ -ujr:qzdb ;yu9d2ob /2 kru i ;pcc+qkf he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moon enk8a b:4ypeckbc jegsc+2; , w0ters 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 temper:,8s ;b+0kecjacp2 k4 ybcwgeature, 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 gas m*1 z boj62i ydilg vcj+nac*lzw1,vp 8f7 .a(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 we(mb:e:qj-5g pn 7 7pttt-sg of 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 atmospherig:hy0og41e 6c) cxf ybc pressure at the surface of the Earth, estimate the total number of air molecu : egogb16c0y4cfy)xhles in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules conta+v d;/9jkxjpptm7y3lined in a 7.6$-m^3$ volume at 4.2 atm if the total amount of nitrogen is 1800 mol?    m/s

  A standard cylinder of oxygen used in a hospital has gauge pressure = 2000 pk5mb/i 2e p5lmsi (13,800 kPa) and at T = kepb li2/m55m259K How long will the cylinder last if the flow rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liqui9 d;j 8sobukk+y g*)vdd 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 gasolk8mk10efohl 7 ( lur7hine 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 snuglgtc1c;q gko 8 e/;nar;y 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 gl d:u7e+vkbza / m8ody3ass 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, add qc9x b 3ha5oer6ke8gq:dp5 23qyf0 vopted 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 charged37*sys pvo3l n, has a pressure of 195 atm at 20$^{\circ} $C. The volume of the tank is 11.3 L.
(a) What would the volume of the air be at 1.00 atm and at the same temperature?    L
(b) Before entering the water, a person consumes 2.0 L of air in each breath, and breathes 12 times a minute. At this rate, how long would the tank last?    min
(c) At a depth of 20.0 m of sea water and temperature of 10$^{\circ} $C, how long would the same tank last assuming the breathing rate does not change?    min

  The escape speed from the Earth8)e7obq n dh2 7c;qkcy 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 against gravity by tennis balls thrown v9drj9m j .cip4b ny-n7ertically ui-pjbmj9nyn4c .97 dr pward at it. How many tennis balls per second must rebound from the lid elastically, assuming they have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter (spherical) pks( u i82w6lpbubble 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 kl62iwpu8( s pwhen it reaches the surface?    cm

  Calculate the total water vazx +q;vx(.fay por pressure in the air on the following two days: xa.;zf+(yv qx
(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 dens--lyb2 5:y52uflv,xoo)- mnean rvuvity of iron at STP, and when it is a solid deep in the Earth where the te-uy f) ml5 on- 5lnro ,-xv2:uavb2eyvmperature 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 p3( ira1htt8 zjressure, the coefficient of volu(i8 t3trj1z ahme expansion is equal to $\beta$ = 1/T where T is the temperature in kelvins. Compare to Table 13–1 for gases at T = 293K (b) Show that the bulk modulus (Section 9–5) for an ideal gas held at constant temperature is B = P where P is the pressure.

  In humid climates, people constantly dehumidify theiti2h.d q mzv )),5ocuir cellars to prevent rot and mildew. If the cellar in a h 5.)idvoih 2,)tuzqcmouse (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