Which has more atoms: 1 kg of iron or 1 kg of aluminum? S9kq3jn rrvh067i 5 +tlivj o7uee the periodic table or Appet j7vv hqr63u7o5ji9 kl 0n+rindix B.

Name several properties of materials that could be exploited to 3*7utcibcweby , ;qu mi ln;r8h;j6snt ow ;*.make a thermomet;;tj ;c s*c*uiyub h tq6wmn,b3 ;i8n7 r.owleer.

Which is larger, 1 C jvk,k)tx9 sl0 $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with syste o j7r;(sx7+2 xl6eycqyhls p.giv2m9m B, but B is not in thermal equilibrium with system C, what can you say 7lm x;plij6(2h2 e gsy+x.c 79 qsvryoabout the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminu5w5.-suwdr*g l uih m0m riveted to a strip of iron. When heated, the strip will bend. Which metal will be on the outside of the curve? [Hint: See Table slw- rdumhg.5 i0u5w* 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 evwnf4+z tk4. kxpansion $\alpha$ 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 tr- a7 seo+jo7to 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 c-oajr7ets 7 o+ontact 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 awncj+:mllgjk (r04mphtqv bo):7 s0 , section in the shape of a U. W) 4tm0:bv7qsj p j:lgc0,(hrlno +k mwhy?

A flat, uniform cylinder of lead floats in 0)j w gunquz nbgf03eyma0*/jub 0d43mercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermomet e-ia jo15h4nfer is first placed in a hot tub of water, the mercury initially descends a bit and then rises. Exp-i aef1hj 4n5olain.

A glass container may break if one part of it is heated or cooled more ra*i nl w4e8z rim )o2v:zio5, czry/2yopidly than adjacent parts. Ei)re/ : ,*i5lvmzyno8rwoo zicy24z2xplain.

The principal virtue of Pyrex glass is th uhxl474de17c jpy40yjzofk4 at its coefficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyro jh4dzk4c 74y7f eux4yl1 jp0ex.

Will a grandfather clock, 8dxv dm- t58cxaccurate 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.8/bbs6t-w 5s xt. t0stvvkt:h i3 uec cause its bottom and top to bulge so badly the can will not stand up. What has happ-i0kwv.s t8:/sttx .vbtsch e t3 u56bened?

When a gas is rapidly compressed (say, by pushing down a piston), ity7jkp6tld / ( b:9u2.vwk/kk go m1ades 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 etu ( pkd/ g9kwby 7/ljvd.2o6kak :1mto the momentum of molecules when they strike the moving piston.

Will the buoyant force on an aluminum sphere submerged in water increase :bm wkb4hfy*+or decrease if the temperature is increasbmf4+bk * why:ed from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from b h+k2hgg93.ikm+ ogba/go1z kinetic theory and the relation betweeokg.h2++okh9bg z 3mgabig /1n average kinetic energy and the absolute temperature.

Explain in words how Gay-Lussac’aq v tn79l rx*rswpk: u:22hx6xgq8j0s law follows from kinetic theory.

As you go higher in the Earth’s atmosphoqj8gx31) k;hfn dc ok1v:7qdq,1 pgsere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed an object must havq 6hw)ag e35tqe to leave the Earth and never return. The escape velocity for the Moon is about one-fiftheq65 wg aqt3h) 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 waqtt5z3h8a t- nu8v9fa c/d(rd7a b h8uter at room temperature. What can you infer about the molecular properties ofhd5-tzu tnrc( a9 ud/t3af8h8a v 8q7b one relative to the other?

Explain why a hot humid day is far more uncomfortaax:2 ieh, )f6wa+7ugh wvjih9ble than a hot dry day at the h6h:wfvjauhw+9x ,7i)e gi 2asame temperature.

Is it possible to boil water at room temperp ,twf1v +97pk iztvd0vu; ,rgature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is thes ( ip 9 lbscj79h0n1nwkbxb-+ same but the humidity is different. sk(1n ixb7n wl jsh-b0bcp9+9Which is more dense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerous to open the radi y*q)wngfpbj 2m9m+ .hator cap of an overheated automobile en9qm. pj b g+*nyhm)wf2gine.

Why does exhaled air appear as hh ,x eofts31d.d8,cm 7x0fvha little white cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4xk 4zs8qvj ku/4t t)x7-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.ze g3icv7 3o2e5-gram gold ring compare to the number in a silver ring of the same mass? 3 o7ce3e2vzgi$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is ofw ried d, )n5cfq43we1ten taken to be 68°F. What is this on the Celsius scale?1)4f5dwqi 3n,dwc ree   $^{\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 temp+kwzto 0m;;fnevoy ib9qf ,9v )*.hdc eratures 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 thermometl-e*o01kl jnk er, the alcohol column has length 11.82 cm at 0.1 ll 0eko*nj-k0 $^{\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 lpxo +kt8) anbfh(1 nm4ong (20 $^{\circ} $ C). How wide should the expansion cracks between the slabs be (at 20 $^{\circ} $ C) to prevent buckling if the range of temperature is -30 $^{\circ} $ C to +50 $^{\circ} $ C?    m

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

  The Eiffel Tower (Fig. 13–29) is built of wrought iron approximately 300 m *8adm, ar(xxntall. Estimate how much its height changes between July (average temperature of 25°Cdx8,x*r(aamn ) and January (average temperature of 2 $^{\circ} $ C). Ignore the angles of the iron beams, and treat the tower as a vertical beam.    m

  To make a secure fit, rivets that are larger than the rivet hole arebs ixjy7.xtaal4 :2o ,/tk v4d 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 hol :/dsxoka4jtyx.tv,b7 2 a4lie 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 azfbo.-+ :s5(+rzorj u a:wt yja/bun:t 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 6t:mf /w ;ze kc+/j evlp)ush,in volume if it is heated from 30) w,zcs;et+m ev 6ulhfk/j:p / $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350.0 mL of water at *fi7rinr(3 hi100.0$^{\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 w6i f/rolyjmsb( ll9- +ater 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 irov2fj 9is52jab4n.xfg;l 9q aa n. 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+k/l79lev8kt koo t;zo it can expand in essentially one direction only, show thatek9z+v78/ol k tl;ko t the effective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change i zcs)pilm ha5bfa1jh7p6x q42 , ;4pekn 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 oqcm/m c*3b,n+s / pxk9( ewkgaf linear expanp nmkm/sxgqac9c 3*/(w+bk e,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 sdnz425q/n+r*mz1tnsgex gd f 9*zc h4olid, $\beta$ = 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 keep6qh19kl 6wtq:s56say5vggc(zi.cj w s perfect time at 1sv s696ky z5jiw51:qq.g(lwchtgca 67 $^{\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 thermomet0s25e3 4ttzn mk9pksabu lpa +,w9l/zer has an inside diameter of 0.140 mm. The bulb has a vpszak zmewk2paut, 0ll9 s 3n+t4/b95olume 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 wc6btt * e1l(vmhq8:sf heel of radius 0.41 m is rotating about its axle on fric vtbel8(1m*h fs:qc6ttionless 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 desir8tx7grdn b2e6+no y t j+7xq8bed length when at 15°C. How much stress is required to keep it at th x8bjeybd6o+2n8t7tn+x q7 rgis length if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-sectional area 0.. .nbw/.vjn4zo r.huz041$m^2$ 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 hh1ybvv qdsi(um - s2b88:y0vkv3- mfat 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 followingu- i,w1uv4c v.f9z)r+oap vgy 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 temperatg k ,p4gfh, .+(ebflp:niu p,sure on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior a r68u gxz6bt o/5 bj5q*:sprqof the Earth and Sun are about 4000$^{\circ} $ C and $ \times10^{6 }$ $^{\circ} $ C respectively.
(a) What are these temperatures in kelvins?    K    $ \times10^{ 6}$K
(b) What percent error is made in each case if a person forgets to change $^{\circ} $ C to K? $\approx$    %(Round to the nearest integer) $\approx$    %(Round to three decimal places)

  If 3 $m^2$ of a gas initially at STP is placed under a pressure of 3.20 atm, the temperature of the gas rises to 38.0$^{\circ} $ C. What is the volume?    $m^3$

  In an internal combustion engine, air at atmospheric pressure and a tempe v(0w. exk86gjujp*bf rature ofp( 80e*gxbu. j fvjw6k 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 density of oxygen at STP using the ideal gas,. ggo( v:r 5llvf s)qd0(-xcldh(hhm law.    kg/$m^3$

  A storage tank contains 2173l3bb1 h 9p )im. qrxzi:6xygvvxr 0y.6 kg of nitrogen ($N_2$) at an absolute pressure of 3.65 atm. What will the pressure be if the nitrogen is replaced by an equal mass of $CO_2$    atm

  A storage tank at STP contains 18.5 kg3(c qcfk:ajpl0f (k /k 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 heliump5p .f(*r4wi n;yxt2;arhu 3xh4xrpy gas is at 10.0$^{\circ} $C and a gauge pressure of 0.350 atm, (a) calculate the volume of the helium gas under these conditions.    $m^3$
(b) Calculate the temperature if the gas is compressed to precisely half the volume at a gauge pressure of 1.00 atm.    $^{\circ} $ C

  What is the pressure inside a 35.0-L container hol4t17 iujrx t kce.5zmnz3 9l9lding 105.0 kg of argon gas at 359cueiz z7mk1 n xlt 34.t9lrj85 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 k-npd4 y/l 3wi ysnj7* uaya;3sg of $O_2$ 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-i( mdp/v qx t5-di*bv by heating the air inside the balloon, which makes it less dense than the air oqv*idmix - d-5pt/vb(utside. 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 air*c u(v h31qj; 3bflp xyb2i5qr 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 l- ckd,) *-5b umfhgtg18.0 $^{\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 xxpdq s, 5pqcyvm6+eel9ji1 ylq.141 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 of molecule1asn nc,y;l 0ns / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there .i64zxcc- (pfkce(7ww ap o3j in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) moles,3p7 *jvrj)n5jce7k k;p)u t gu    $ \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 mn z 56p(1ejun/ftjkq(h40y y5.1$ \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 ejz1bsoq79 3g w n3d0)hj kmkh4ach 2.0-L breath you inhale that were also in the last breath Galileo took. [Hint: Assume the atmosphere ismwh7kn b3hd04)z1j3jq9osk g about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy oonv* qx,6,hga gko8;ont )k,af an oxygen molecule at STP? gvh;)k8, oaa,tk x* 6ooqgnn ,   $ \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+lnw+2 gd; wau miy)y+ atoms near the surface of the Sun at a temperature of about 6000 K. w)u+nl++wa 2dgi; ymy    m/s

  By what factor will the rms z i 9h) di(k+ho m)1dyyhab/a;speed of gas molecules increase if the temperature is increaseihk d/a19h+ob zm)iy;)y(h add 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 spee v fi4(4.tesfqds, given in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, ans.ev4q4t fi( fd 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at 2resrx7 ht72f6 .kely4z6lps 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 whiihwk5fl ux 8ty+qi/o av12- w.mood/+ le its volume is held constant, by what fty o1+ lv.mkafox oui+2ww hd5-q/8i/actor does $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is give wdrmh0zx t/y.-4/ vlvn 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 l - ;tfn),hasttwo gases at the same temperature, the ratio of their rms speeds is equal to the inverse ratio of the s an ,sh-;tl)ftquare roots of their molecular masses.

  What is the rms speed of nitroghm s,(g(q9yf1 5hpmyq en molecules contained in an 8.5$-m^3$ volume at 2.1 atm if the total amount of nitrogen is 1300 mol?    m/s

  Calculate (a) the rms speed of an oxy2dj(9zk r/,-olp fu bpgen 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 g il5 o(ea8s xwidw9 *(nic-7oSTP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whosjv:rq 9kx7.mr: kp.jd2pml.h e molecular mass is 89 u in a living cpkr9mjl..p: h.xv2j:7q kmr dell 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 wsjnce.9 r34)k 0vqgsbritten 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 e7 .-+*/ dzotiiy vu;6wnw-gb2xeqhduranium, $^{235}$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 pressmnq c rp)*wlf37tyu ./ure, 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 pressk kb. x ab5c58svg3;v.dyh-ult y0xsh.2 r jt+ure is 0.01 atm and the temperature is (a) 90bckxg t y;xv+..vk58th a sulrhj2d3.syb- 50 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximat b*vthilcz *u z7bavdq.39)r)ely) if the humidity is 50% on a day when the temperature is 25 zl7r buza hv)q3b)9ic*dv.t* $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water .vobyf-u / 7mk6p tth,boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a p* kvh )zzytdhw4)hn-1articular place in the mountains is 0.72 atm, estimate t h y1hzhtvzd-)nw) *4khe temperature at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the pc8zump) m8s9t c /ri6aartial pressure of water is 530 Pa and the relati)s8/mztc9cr pim6au 8ve humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of wataedgy 0:idew;r:bn n/m+ .1teer on a day when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure 8i(i8ojcnqo x 2e7)lj2u 5i mkinside a pressure cooker if the water is boiling a cko(q )ui7jme8ix2o2lj58 nit a temperature of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a dr9w00. m gfmhroom of volume 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 dec ; s;2- ogfs rb4 nps.52-cxy/kulzfiw 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 molecule (see T1p oon8 b6f;g 6)dbtmiable 13–4) to diffuse a distabdofg i61o6 mt; )b8npnce 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 ofd u:wpy2 3*go gv4li/v insects to the interior through tiny tubes called tracheae. An average trachea is about 2 mm lonu2*:/v4 ldv3ggop w iyg and has cross-sectional area of $ 2\times10^{-9 } m^2$ Assuming the concentration of oxygen inside is half what it is outside in the atmosphere,
(a) show that the concentration of oxygen in the air (assume 21% is oxygen) at 20$^{\circ} $ C is about 8.7 mol/$m^3$ then $\approx$    mol/$m^3$(Round to one decimal places)
(b) calculate the diffusion rate J,    $ \times10^{-11 }$ mol/s
(c) estimate the average time for a molecule to diffuse in. Assume the diffusion constant is $ 1\times10^{-5 } m^2/s$    s

  A precise steel tape measure has been calie;(ze ;qxrl 3gbrated 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 m*:n55dsr: pv-vg uhl neasure 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 normal room temperature. How muchkh54;au zt qx n;ub+b( error will be made in a recipe calling for 300 mhbx ubz;kq n4u(;a5+ tL 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 (rrq0* xq jc-zgm6 u g7u(ojx/d.r/cegas cylinder is initially 28 atm. After many balloons have been blown up, the gauge pressurj/c c0/r( 67.qq u m j-ugdx*(gerozxre has decreased to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air molecules in 7) h+o-:ldqpwa sim+7(egjs q a room of length 6.5 m, width 3.1 m, and height 2.5 m. Assume the temperature il:hq7 si( +s+jp7edowm gq)-as 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is about one atom per aynr/w tw)(4q $cm^3$ 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)mv+0tl j-dg l e(9qpj techniques is about +g0ve ll9(jjm) -qt dp$10^{-12} N/m^2$ 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 58szcx8( x bay8 9ne 9ni7dyonim+2,jy .5 L when 10 m below the surface, to what volume would his lungs expand if he quickly rose to the sd8i an9mby,yn2y( cseo x 9j+i87xn z8urface? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmotf8ur-7oif9n ezgr yfe,z2+8 na5l 0e sphere 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, the nose of a space vehicle must ze-or20ar il,8tgze785n+euf9nyffbe 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 is increased fromm.x2d9 7 rq zt*muf5z/9hg* wc 7yrlko 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 770epl (k a3+2xgmm$^2$ (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 Earrbs a 7qi6a6d6th, estimate t7 ba66das6q rihe total number of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen moleu6zly-nk-w5 1cci y,c cules contained in a 7.6$-m^3$ volume at 4.2 atm if the total amount of nitrogen is 1800 mol?    m/s

  A standard cylinder of oxygen used in a hospital has gauge pres1)*tu.4 gvw1cf1 vimz o )tfqhsure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if th)f4 z11 vw.fc1hvmit* gout) qe flow rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liquid merc9x5bl ahok- a/no) ip86h1yeq ury 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 gasol27g j1eh )i)ajstk,z,rw-g wj ine 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 snugly around the Earth’s equator at 2c9ya )rb wg*ik2w(g ;-j3mysh 5$^{\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 tightlyloaa:+lyr oyj7o1) 2k onto 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 standar-1hbw.tc )n vwtqfb0m j8 i7u5d, adopted in the 18$^{th}$ century, was a platinum bar with two very fine marks separated by what was defined to be exactly 1 m. If this standard bar was to be accurate to within $\pm1.0 \mu m$ how carefully would the trustees have needed to control the temperature? The coefficient of linear expansion for platinum is $ 9\times10^{ -6}C/^{-1}$. $\pm$ =    C$^{\circ} $

  A scuba tank, when fully charged, has a pressure of 195 atm ar p8p ntkj(ie9dt) x7*t 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 z w.gril/v3d;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 suspended against gravity by tennis ball.+ ithuw9q gt-s thrown verticallywu9 . qh-+gtit upward at it. How many tennis balls per second must rebound from the lid elastically, assuming they have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter (spherical) bubble of air fromjcoch+y2 +*uwaf2b 8p/s 6mow a depth of 14.0 m in wwm28uo+ f6+b*osca2y h/pj ca lake. Assume the temperature is constant 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 fo;z 0uaea-ih+u llowing two days: hu 0z;uaeia+-
(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 iro),vw7llyd ppj4k ajsdh:d+7;n at STP, and when it is a solid deep in the Earth where the temperature is 27a+jp) 7,d:dskp j4wvh lydl;000$^{\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 gak v6-21baxqu gs law to show that, for an ideal gas at constant pressure, the coeffik21u 6 v-bxgaqcient of volume expansion is equal to $\beta$ = 1/T where T is the temperature in kelvins. Compare to Table 13–1 for gases at T = 293K (b) Show that the bulk modulus (Section 9–5) for an ideal gas held at constant temperature is B = P where P is the pressure.

  In humid climates, people constantly dehumidify their cellars to preveb9 t-1fjsd8j * wk8*d 4fknvlrl(d a4znt rot and mildewl4jw9a v j1dff*brl8k nz4sdkt -8d(*. If the cellar in a house (kept at 20$^{\circ} $C) has 95 $m^2$ of floor space and a ceiling height of 2.8 m, what is the mass of water that must be removed from it to drop the humidity from 95% to a more reasonable 30%?    kg