Which has more atoms: 1 kg of iron o.vm a+em sh*2br 1 kg of aluminum? See the periodic table or 2m a.bve+msh *Appendix B.

Name several properties of materials that coz-k4mfh v4iv*xz 8v63tf t 1gould be exploited to make a thermometer 8f v*4tvmx4z3t zg hiko1vf6-.

Which is larger, 1 C 1s *qzbeb)rang da 9a b5i;59y$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B is not in thermal eqd3i 4 /whf+hdodvn4h 4hly cm1+t7h+(xtf-mcuilibrium with system C, w34ftl d /v4(n h1mdh4t c- +ic+fywhoh+dxmh7hat can you say about the temperatures of A, B, and C?

A flat bimetallic strip consists o:v3vo: p 5q oof tf7s65(wnffhf aluminum riveted to a strip of iron. When heated, the strip will bend. Wh5v5w ofq ff6ns:othvfp7(o : 3ich 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 coeo7lzn0j2vm/ 9ik n+y byd 86b-mokwn7fficient 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 used to control5sy kwyhp:3 l9cc s7r8cm90bd a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bondedkwsp ysccdrbchm5 7 9l 90:3y8 together. The electric switch is a glass vessel containing liquid mercury that conducts electricity when it can flow to touch both contact wires. Explain how this device controls the furnace and how it can be set at different temperatures.

Long steam pipes thagq:xu x+w- 9ij5z9j yxt are fixed at the ends often have a section in the shape of a U. Wh q9:xu+-9z j5xwxgjyi y?

A flat, uniform cylinder of lead floats .f iiczrm x14:in mercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometer is first placed in a hot tub of water, +gf0kosim pu3/v;ae .the mercury initialsau0me3v;/i.p kf go +ly descends a bit and then rises. Explain.

A glass container may break if one part of it is heated or cooled more r,v fv lcnz;,;lh*xc k3e;gf e67x4ii xapidly than adjacent parts. Explaizxex 4evxck, f,hg;l*fc;iln 7;6v3 in.

The principal virtue of Pyrex glass is that its coeffi4crsv - vv.vp-cient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain whcvvp-sr.- vv 4y this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accud q.,hgbu 02j/x zcci4rate 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 px*22p9otw,kg q-ka nf6a2m mwill cause its bottom and top to bulge so badly the can will not stand up. What hasato, q-mp2k962xk*wmpagfn 2 happened?

When a gas is rapidly oda znu.) qj0l m62.hw-j q0ve8z)dqrcompressed (say, by pushing down a piston), its temperature increases. When a ga)vmrq a62. h 0qju)dz 8ezn d0.qoj-lws 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 the moving piston.

Will the buoyant force on an aluminum sphere submergwcf(;+c2z:1 f l mpdieed in water increase or decrease if the temperature is increzdf+wlif1cm e2p:( c; ased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’+(*n05dqfoyuyzo9l oz3j qv 4+3nqei s law follows from kinetic theory and the relation between averaoejzynfonz oy5qq3q4+v9 + *( ud3li0ge kinetic energy and the absolute temperature.

Explain in words how Gay-Lusnl7wr-kmnr+wm3o +h, 8q:kob sac’s law follows from kinetic theory.

As you go higher in the Earthj)7jwwra 88wtg,:k6 j mxstkj-p* yd9 ’s atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed an object must havj .c-lk .he1ujrm00mp e to leave the Earth and never return. The escape velocity for trj1-lhp.m mc0. j euk0he 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 at room temaofa ,.me2 nunz *r -k/wgpo2.perature. What can you infer about the molecular properties of one r er* zomfk.o2nau.-/nag, p2welative to the other?

Explain why a hot humid day is(* t6 suw 6*u0qfds/ z4dfbtyi far more uncomfortable than a hot dry day at the same temperaturq6z(dtuf* s0wd bs4yt if6 /*ue.

Is it possible to boil water at room temperature (20 +; -/ p hxfglswup4xi,myl*e4$^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperatuw 5 cd06sbdm,ure is the same but the humidity is differeddcs6w 05m,bunt. Which is more dense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap of an kkys)mj-i- /fux0ax -0ejj 4ks7o+.fc x 7oploverheated automobile-/-kx 0jf+fk4lscj.po7xs70 aoiuk)m -exyj engine.

Why does exhaled air appear as a little white cloud in the winter (Fig. 13–28)i)3 jdt9qfa whf/bj-f4l8tj1?

  How many atoms are there in a 3.4-gram copper penny?:cbbzr- a(s48d epo t+   $ \times10^{22}$ atoms of Cu

  How does the number of atoms; zq-d66; hoqmgmkv: u in a 26.5-gram gold ring compare to the number in a silver ring of;q :6oqhm d;v-u6gkmz the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is ::m x, +mo lpv,lr+g2gxdshr0often taken to be 68°F. What is this on the Celsius scale?rl0 :s x,r:ogpmm h+,v2l+dgx    $^{\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 lo( a,o r/nzuh y4q-8d; u4um0;tuklxf jwest 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, dqv:nx9 clu *6t,twl)the alcohol column has length 11.82 cm at 0.0tcu,dn:xv 6wll)t9q * $^{\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 (20p ;vc;zf 302kdl3 yjhc $^{\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. -t3 a9 h:xvlr r2ps)cp13–29) is built of wrought iron approximately 300 m tall. Estimate how much its height changes between July (average temcv psx h9arrt:p3-2l)perature 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, rivets that are larger than the rivethy6x7( d5nkgv 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 diameter a( y7d5h6gnxvkt 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 ay4:syqhj)i;)9- em i qvz siq4t 4 $^{\circ} $ C is $ 1\times10^{3 }kg/m^3$ What is water’s density at 94 $^{\circ} $ C?    kg/$m^3$

  A quartz sphere is 8.75 cm in diameter. What will be its change in volume if itq0sczm /nk,s jx1 a9j3 gvve*. is 0/e q1*vkj ,9 g 3mxsvc.ansjzheated from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled tao 8oipl2( z1ho the brim with 350.0 mL of water at 100.0$^{\circ} $ C. If the temperature decreased to 20.0 $^{\circ} $ C, how much water could be added to the glass?    mL

  It is observed that 55.50 mL of water at 2uanj x-:4wrj z::d ah :fd1k8d0 $^{\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 inlf(3bd94.ne bzx3 jrumiicpo3 .o7 2b a ring made of iron. At 20 $^{\circ} $ C, the diameter of the plug is 8.753 cm and that of the inside of the ring is 8.743 cm. They must both be brought to what common temperature in order to fit?    $^{\circ} $ C
(b) What if the plug were iron and the ring brass?    $^{\circ} $ C

If a fluid is contained in a long, narrow vessel so it can expand in essennb -)taoe((m ytially one direction on o()nbemty( -aly, show that the effective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the ch9jvq ycql1i-sqhq/v ;w9)( eaer;:z yange in the density $\rho$ of a substance, when the temperature changes by $\Delta$T is given by $\rho$ = -$\beta$$\rho$$\Delta$T
(b) What is the fractional change in density of a lead sphere whose temperature decreases from 25 $^{\circ} $ C to -40 $^{\circ} $ C？

A uniform rectangular plate of length l and width w has coefda.4qh uew 21as-2rikficient of linear expansiod1w .a hiu2aks-eq4 2rn $\alpha$ 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 sol9fxhi*:i o5ms id, $\beta$ = 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 perfect ti (:pxsx5 mkahg:x 7otj 2 egb-0q4mwp/me at 17pmo( t2eh: 7 :0 xpxkgxgmasq-b/5j4w $^{\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 the,u:/ .vujkb9 d pjq1ejrmometer has an inside diameter of 0.140 mm. The bulb has a volumed:j/ujq,pev 9k1b. ju of 0.255 $cm^3$ How far will the thread of mercury move when the temperature changes from 11.5 $^{\circ} $ C to 33.0 $^{\circ} $ C? Take into account expansion of the Pyrex glass.    cm(b) Determine a formula for the length of the mercury column in terms of relevant variables. Ignore tube volume compared to bulb volume.

  A 23.4-kg solid aluminum cylindrical wheel of radius 0.41 m is rotatibt evjq3 )ylp:nx / 1*8 w(.xslndf0miit*be8ng about its axle on id81qtxpsi )njv 0. b/etm elw8:yxf3*bn*( lfrictionless bearings with angular velocity $\omega$ = 32.8 rad/s If its temperature is now raised from 20.0 $^{\circ} $ C to 75.0 $^{\circ} $ C, what is the fractional change in $\omega$?   

  An aluminum bar has the desired length when at 15°C. How much stress is reqtsdqqlok78c;gglkqo2,8w0 9-rv 1 d fuired to keep it at this length if the temperature,kq lkws2q t-c8rgd9dq1 of vgl;078o increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-szx-lmr4)e, w*adet7e ectional area 0.041$m^2$ is rigidly connected to two vertical steel girders. If the beam was installed when the temperature was 30$^{\circ} $ C, what stress is developed in the beam when the temperature drops to -30 $^{\circ} $ C (b) Is the ultimate strength of the steel exceeded? (c) What stress is developed if the beam is concrete and has a cross-sectional area of 0.13$m^2$ Will it fracture?

  A barrel of diameter 134.122 cm at 2k gp:ac2 p1lixrk3d/ t-i.zj20$^{\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 teg.im ms/3 sfx)0vx,f mmperatures 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 whaa:70f(chu x)we1v +:yjml lwwl +i h:ft temperature on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the int edr 6tui;bk;et.iy:n9pmyc l3-l, 6xerior of the Earth and Sun are about 4000$^{\circ} $ C and $ \times10^{6 }$ $^{\circ} $ C respectively.
(a) What are these temperatures in kelvins?    K    $ \times10^{ 6}$K
(b) What percent error is made in each case if a person forgets to change $^{\circ} $ C to K? $\approx$    %(Round to the nearest integer) $\approx$    %(Round to three decimal places)

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

  In an internal combustion engine, air at atmospheric pressurecae +yjj0tm w,s(/,ya and a temperature of aboua+myws t j(0 /y,ecaj,t 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 ST+ kj9knh+f49pt3mk:ateiax 3 P using the ideal gas law.    kg/$m^3$

  A storage tank contains 2 g(q. 7vy3rnebk9uw7r1.6 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 kg of 42 np*vph9vr xnitrogen ($N_2$)
(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 i0 h(-zlfdq; x5 sbjz apsd;eq)n,pe).s 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 35.0-09jsh obxq+ y ei6-g1pp1yb 7gL container holding 105.0 kg of argon gas at 385gp7j9biphsyyx16-+1 q e 0ogb K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kf8n bnleqv5l(11 xbc 9g 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 by heating a4c)i -3rizz *zzda: 2yfvv 3 g4xnkm7the air inside the balloon, which makes it less dense than the air outside. Suppose the vzx4a*drgzzm3 4k7 3c-f2 a)yi zn:ivv olume 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 :cb /cqrm1*+.jepyza hr2 - bdair 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 t.hqm gdc3q/rn 0rzx8ox1k.418.0 $^{\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 ,5alac06jbb 3jkp39 vsyf 8 esydyd+ f 5tt+j/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 molecules (th9ku5rd smzt64 d*a / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of wateru. qmyzk*8 2mlbm) 0cr are there in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) molev:0ac) ,be(j rlp,a qgs,    $ \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 volumeyxx, 4kx a f6t9jit2q0 5.1$ \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 mwj9wz dbg93u1095wlo8zlot1b5 r rjair are in each 2.0-L breath you inhale that were also in the last brj5d19ol91or 3 jbt8rm5w90wuzw zg bleath Galileo took. [Hint: Assume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of an oxygen molecule at h**rg du 4fsqm,nla5k b2 wih 5u;foyur2/22 zST4 nhus uuk *5a; l h2gfiqr2yzb, df/2r5m*2owP?    $ \times10^{-21 }$ J
(b) What is the total translational kinetic energy of 2.0 mol of $O_2$ molecules at 20 $^{\circ} $ C?   $ \times10^{3 }$ J

  Calculate the rms speed of helium atoms near the surface of the Sun atvvs .c2h qeb4, a temperature of about eb,cqv2 .vhs 46000 K.    m/s

  By what factor will the rms speed of gas molecules increase il6)r-g2 uq q xl:wxlwhm x9s;,f the temperature ism hrx:l; 9q6,x)2lxsu-lqw wg increased 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 gox i :*edzy l+7,l8klkm/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. *k 7ylgo,z +ll8 x:ideCalculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gg( zsim*v3rv dl( vv:;c1;umzas 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 aw-8;+rthsx sb gas is doubled while its volume is held constant, by what factor do+sthwb 8r ;-sxes $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is give0+qvo00o/;hjoekp wh, - mek nn 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 temperature4bne9kg,6 e5ec1sbjr , the ratio of their rms speeds is equal crbb,9 e1sk gee6 n5j4to the inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen v:qd.q bd*+ d5*8nrm(uzrje r 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 oxy4mglmyrerpc+gdcch 83l3u7mdl( 7+1 gen 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 STP6*hv1vnsk6b7zk 9 u wh?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular mass is 89 u in a lih4. xs2ms6dmqylb 8 e8vi8ms8hd.b sx m64ly2qe ng 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 g9*zi j1xc/ b/wpk7 a.ke3w wvtas 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 ur2 v3s ylcr14+r3 bbhtv be5kd*anium, $^{235}$U and $^{238}$U (the superscripts refer to their atomic mass), can be separated by a gas-diffusion process by combining them with fluorine to make the gaseous compound UF$_6$ Calculate the ratio of the rms speeds of these molecules for the two isotopes, at constant T.   

(a) At atmospheric pressure, in what phasle.z6h fkuc -6es 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 q - .j3ae9ql,errbd09b3j luvand the temperature is (a) 90u9-b3 ea,qvdr0beq9 lr .jj3l $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humie ,:x /p4esayzoh )9wedity is 50% on a day when the temperature x,/h ya)eoez : weps49is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place whw25hk0z-xqu1b y kp9p ere water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a parn4e7q /pt j3e1*dd .j7xch 6i3cf lxe,dr /fjsticular place in the mountains is 0.72 atm, estimate the temperature at which water boils frf/ej , hixjd 7tlje4c3ds3n1*/ pqcedx76.. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure dd;.k(ghd ys2, hqj y3z92g7oo;+cdxipdz )d of water is 530 Pa and the relative humidq,g 2 hc)oz h(; s xi;ddddyk.p9+7zgjo23dydity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial press36l.qd :pl w 3umkaeq:ure of water 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 the water is bo1swfw82u 8w/yqe)3fk0 ws g zhiling at a temperature88fsez3u1fw) q yww w2g0kh/ s 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 voluq4bzz3qnz/pc 2)n wtih 22ij1 me 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 drta ku8eqr i/, tmq j9u-z 85-mxfdw27ew 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 Tabzy )d4kpln rs -bqzt0b7mrd y50* tl:/le 13–4) to diffuse a dip :z rknz5bmb)slyl ydt-/ t*qd4007rstance of 15 $\mu m$ in water at 20$^{\circ} $ C if its concentration varies over that distance from 1 mol/$m^3$ to 0.4 mol/$m^3$ Compare this “speed” to its rms (thermal) speed. The molecular mass of glycine is about 75 u. t $\approx$    s ([color=rgba(0, 0, 0, 0.85)]Round to one decimal places) $v_{diffuse}$    $ \times10^{ -5}$ m/s
$v_{rms}$    m/s

  Oxygen diffuses from the surface of insects to the interior through tiny tubes cd1w ubj +rg1;lr-ept3 alled tracheae. An average trachea is abuwljebrg -dr3+; 11tpout 2 mm long and has cross-sectional area of $ 2\times10^{-9 } m^2$ Assuming the concentration of oxygen inside is half what it is outside in the atmosphere,
(a) show that the concentration of oxygen in the air (assume 21% is oxygen) at 20$^{\circ} $ C is about 8.7 mol/$m^3$ then $\approx$    mol/$m^3$(Round to one decimal places)
(b) calculate the diffusion rate J,    $ \times10^{-11 }$ mol/s
(c) estimate the average time for a molecule to diffuse in. Assume the diffusion constant is $ 1\times10^{-5 } m^2/s$    s

  A precise steel tape mfp2af(j) h(yab,u 4x beasure 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 tape4w14+*6tzzbf e +v ypnkwvy:o measure 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 much er.r5)*(x z1jjo5 pazfv,h ;xblxg 4xjeror will be made in a recipe calling for 300 mL of cool water, ifr, z;p)(gxxaj 1jobvxzjx.*ehfl554 the water and the cup are hot, at 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in a helium gas iu0-htv9r(r g cylinder is initially 28 atm. After many balloons have been g r ir0h-9v(utblown up, the gauge pressure has decreased to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air moleculw8 9xjcec2. sq3cdyi- dsaw.4es in a room of length 6.5 m, width 3.1 m, and height 2.5 m. Assu9s2 -x.ws4d wcj acq3cide.y8 me the temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter i1x ,a t5wlz) lo8w.ft1mre sb2s 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 csiukf,3v* 8 xvacuum techniques is abou 8fs*iuc3vx, kt $10^{-12} N/m^2$ 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 th rie-0 x4 ti;xy m0bserq:cb3in;8zz3e surface, to what volume would his lungs expand if he quickly rose to -ieenb qist3rci0b: yrm;xx 83 zz4;0the surface? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmosphere at a speed o*k1huw go.um950ff ax 5x1v jcf 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 special materials; indeed, part of it does vaporize, and this is seen as a bright blaze upon reento5a hv1x.j mu f0*wx9k5g u1fcry.)    K

  The temperature of an ideal gas is increasey)n1)*jstcg bvy 9 tgzc aqf0*,1j;bgd from 110$^{\circ} $C to 360$^{\circ} $C while the volume and the number of moles stay constant. By what factor does the pressure change? By what factor does $v_{rms}$ change?$\frac{P_2}{P_1}$ =    $\frac{(v_{rms})_2}{(v_{rms})_1}$ =   

  A house has a volume of(ip*thz+podpk8kj1y w le/;;y +e 0lq 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 surface of the Earth,h e//b,tgi bqew,.o. e estimate the total number of air molecules in the Earth’s atmos / oe,w,.htbge/be.iq phere.    $ \times10^{44 }$ molecules

  What is the rms speedkngldsjy y) 1m-nl5(, of nitrogen molecules 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 ); -eesjtsot1 a hospital has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will theeost; 1t) js-e 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 x 7 w lyvq3*:5 b)rz kaxlxg8hd(g.-aeliquid mercury at 0$^{\circ} $C. (a) If the temperature is raised to 25$^{\circ} $C, will the cube float higher or lower in the mercury? ----待选择----lowerheigher 
(b) By what percent will the fraction of volume submerged change?    %

  The density of gasoline at 9+l0sb mdmer.wz5 ;m .i:ybhe0$^{\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 tbfameu 3157nb 7)oodk he 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 4i;cl,;tvakgj+gu4 bu w/s.cglass 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, adoptedpv7n*-6xzkz5 hc+pj z3 ,ebdq 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 pressurz4g t 4c+dq)+zyb(mbd e 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 thaac7ibff( u i1e/9jp :e 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 x k-o 9yfomrx,t-.zi*tennis balls thrown vertically upward at it. How many tennis balls per second must rebound from the lid xr9y-ox t.,m-kioz*f 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-diaztdhvtqq d ,w/y) mdw27 3,us(meter (spherical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the air behaves as a perfect gas. How large is the bubble when it h ,m2/tsywdwqqv3(z d7 d,tu)reaches the surface?    cm

  Calculate the total water vapor pressure in the air on the following two daytgdzi88b6 cd8 s: 8tdid688zcg b
(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 in1;4oec oi,bwa the density of iron at STP, and when it is a solid deepb, ooaw;4 i1ce in 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 zo07cz07asgt 4iy qjcrg 42u;gas at constant pressure, the cu4tocgjs2 z4ya ;7 z0qg0ci7roefficient 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 thei9/c(l*(z iou,oadwuwo a gb e ,ecfoh,r8g0/ :r cellars to prevent rot and mildew. If the ouia/9 o(e* ,,z ofor w u8c,c:whbggaeld(/0cellar 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