Which has more atoms: 1 kg of iron or 1 kg of al : b0rkz: sot))ypoa1huminum? See the periodic table or Appendix 0h)sor ak) tz: p:oy1bB.

Name several properties of materials that could be exploited to m-: ugpocu:g7q ake a thermometer.q: ouc7u g-g:p

Which is larger, 1 C 3(rxmq.kxudb ,gh 4 l;$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equ:ues )lvcr)a)gen1 f 0h:od+.g6dd ybilibrium with system B, but B is not in thermal equilibrium wv6d))f .drs::0+hnue ba)eyo gcl1d gith system C, what can you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to a strip of iron. cb.(eyb2jq-yg2 vz.y When heated, the strip will bend. Which metal will be on the outside of the curvejeb(yzygbcqv. 2-.y2? [Hint: See Table 13–1.] Why?

In the relation $\Delta$L = $\alpha$ $L_0$ $\Delta$T, should $L_0$ be the initial length, the final length, or does it matter? Explain.

The units for the coefficient of linear expa:dyz e(-6 ivv8 4qapipnsion $\alpha$ 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 aen k/8w75tl :in 7woqs diagram of 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 flowk5wns7 /nw7t: qiel8 o to touch both contact wires. Explain how this device controls the furnace and how it can be set at different temperatures.

Long steam pipes that are fixed at the ends often have a section in,a d4ec)hxh 6k the shape of ah e d6ca4)xh,k U. Why?

A flat, uniform cylinde cb*reu1i 5;kpfht,f(r of lead floats in mercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometer is first plactx .e dh k0+l9ubl3e,ced in a hot tub of water, the mercury initially descends uec,lb k3d+ h0lx9.e ta bit and then rises. Explain.

A glass container may break if one part of it is heated or coole67h qf4p txr.fd more rapidly than adjacent parts. Explainf.4q7 6xphf tr.

The principal virtue of Pyrex glass is that its r 22dvm gqn4ra3-k0ja coefficient of linear expansion is much smaller than that for ordinary glass (Tablen0d-r2 qv4a32 kgja mr 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurate a 3* mzxxkr2i :j;,gwddoh* yn4t 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 botwa(r rh.+3g:j-)aspb ui 5ruajtyr 7. tom and top to bulge so badly the can will not stand up. What uryh7wr.gt+.b3-: j 5asa rj)rp a (iuhas happened?

When a gas is rapidly compressed (say, by pushivz 50s3+ cbl gxcr/p5tng down a piston), its temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperature using the kinetic theory, in particular noting what happens to the momentum of molecules when they strike the moving piston.5bpcr 3c0tg zs +5lvx/

Will the buoyant force on an al jwfpx /n9:.7ssd4rc kuminum sphere submerged in water increase or decrease if the temperature is incrnwfkxs 4 rd:c9pj/7s .eased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theory anx41o b*g+ g h64zrgd+go 4hlsdd the relation betwo+gdzhx64d r* bgg44ogh +l1s een average kinetic energy and the absolute temperature.

Explain in words how Gay-Lus)kag)s7ar :eu sac’s law follows from kinetic theory.

As you go higher in ,ek20 f y)jra:i od2kothe Earth’s atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum -+x m *pde+17qq (fzeyn ibll3speed an object must have to leave the Earth and never return. The escape velocity for the Moon is about one-fifth what it is xe q* pe+bqln1y+ i7(m-ld fz3for the Earth due to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than waqrd76bt, agsiq/swe4ed cwvx8.*+4 h ter at room temperature. What can you infer about the molecular properties of one relative to thq*cv e6xt8b adi w.4wg/4srhs7 , qde+e other?

Explain why a hot humid day is far more uncomfortab: / 7 0,qoaokfpkw:zfwb8;is yph/g 1kle than a hot dry day at the same wk:wa: ofog/sypz; /1 8i pf7hk,qk0btemperature.

Is it possible to boil water at room temy *p0;/csehnif:u2al perature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature0s7*sd ce0vyly)r - cb is the same but the humidity is different. Which is more dense, the dry air or the humid air at trycsydb07s-v*) c e0lhe same T? Explain.

Explain why it is dangerous to open the rad oi17. j 6sw hfwr6cl52)fzgxziator cap of an overheated automobile wirxoj67f6)zf1sl .w2ch5z gengine.

Why does exhaled air appear as a little white cloud in th+o9 p*vlc. xnoe winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram coppe)1pbic/ b6xb jr penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare to the nums)jz2i85up i bber in a silver ring of tui)z2i sj bp85he same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this on the Celsius s o t 2,g:47k n8djx+awjchp2.mx(zdng cale? pxnmxdhc2g24dt:g j.(na7,k zo8+wj    $^{\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 tei 8hj7 f1::hyd -jhvjqmperatures 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 y.ko0 8(kaz8q 3 ihclecolumn has length 11.82 cm at 0.e(l 0.h8ki koyzc3a8 q0 $^{\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 (2l y: lcux7kt/x)de1s1 ,dxxw20 $^{\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 approx g8*mu3tb1gt+ ndw,ox imately 300 m tall. Estimate how much its height1+u dgwo mtt3nxg,b 8* changes between July (average temperature of 25°C) and January (average temperature of 2 $^{\circ} $ C). Ignore the angles of the iron beams, and treat the tower as a vertical beam.    m

  To make a secure fit, rivets that are 77tx c-gp)6yrjdsr wg,-94g f.fwz zz larger than the rivet hole are often used and the rivet is cooled (usually in dry ice) before it is plwgc-6fzfy7zrjx)g4rs,7 -g9 tw dzp. aced 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 aa+/z:a 8o-plff l t-1fjc(zd kt 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 5lik-rvs* /n-,pvmdh cm in diameter. What will be its change in volume if it is heated frompldm- h *5vr/-nv,iks 30 $^{\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 100.0a)sa/ g;+ lb 6ihbl2s y(de7lm$^{\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 55.5 *q v.i2e7hqjs0 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 ikci)8 v)d .ujwn 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 containezlxpd 6( k9t,p4rox (bd in a long, narrow vessel so it can expand in essentially one direction only, show that the effective coefficient of linear expansion is approximately equal to the coefficient of volumox krpz(d x4p6,l b9(te expansion $\beta$.

(a) Show that the change in the densityf v3t9tv99zbtec p p73 $\rho$ 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 of linear6i t;cm r:4gzs expacgmt;4s6i :rznsion $\alpha$ 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 solidclv7jw6 ,tm:dly v-i-, $\beta$ = 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 l+*1 flyd z)dvvd7biwzevs,(25 aye9 clock is made of brass and keeps perfect time at 1zv zvl2d*b5de(i,+s ly91 a edw )fyv77 $^{\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 thermo.:i7of*y1avkce 0y o8ur ywm.meter has an inside diameter of 0.140 mm. The bulb hac.:m7 *u1 kefo. yry8ivywo0a s a volume 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 0.4(igj a)he d9vgf3 pv6)1 m is rotating about itspf) vgvd3)hi9jega(6 axle on frictionless 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 requihrhh p*yu 0kh(x tyeg6x)0h,6 red to keep it at this length if the temperature0yh kyuph gex (rhx6*06h,)th increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel zy-(ik0 6l4- 2p jdseb so(mulI-beam of cross-sectional area 0.041$m^2$ is rigidly connected to two vertical steel girders. If the beam was installed when the temperature was 30$^{\circ} $ C, what stress is developed in the beam when the temperature drops to -30 $^{\circ} $ C (b) Is the ultimate strength of the steel exceeded? (c) What stress is developed if the beam is concrete and has a cross-sectional area of 0.13$m^2$ Will it fracture?

  A barrel of diameter 13+hqm, iza0l,r1( f- jqv dk,jb4.122 cm at 20$^{\circ} $ C is to be enclosed by an iron band. The circular band has an inside diameter of 134.110 cm at 20$^{\circ} $ C. It is 7.4 cm wide and 0.65 cm thick.
(a) To what temperature must the band be heated so that it will fit over the barrel? $\approx$   $^{\circ} $ C(Round to the nearest integer)
(b) What will be the tension in the band when it cools to 20$^{\circ} $ C?    N

  What are the following temperature ul 8f2z ,dye+3/cijjv5tgh k8s 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 temperatw)j05n ,eszdw -n1z xture on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun bv+i jwam70s3jz h7-dare 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 ecl+3*qn9 cx wsngine, air at atmospheric pressure and a temperature of about wnxc9q3l *cs+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 dh/k)4bu ;z:dea- h2gzbc2pu oxygen at STP using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of nitr9kmjfwro exj g;ns-((a5w clvp)7+5x ogen ($N_2$) 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 8qm gvo1+*wsjof 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 fd)31jokc3i 4lw u dy4gas 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 holding 105.0 kg d1m8+1u9olph. m s kiw/bow-e of argon gas at 385 K . pu8k+hob9ew11olmi -dmw/s ?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg v7,3 j8o0rfw pj*sjj mof $O_2$ 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 heg4h fva0hos23ating the air inside the balloon, whghso42 a3v0hf ich makes 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 air(a - .i 7bi*tbn g:in,mlz9dxvf8a9ix 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 p-t*l *ca n9ekh*8wcy at 18.0 $^{\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 escapkx67ots c*,44vbisbf es 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 / hyky.,-9et+qll6o zg,n 0a hz$m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of watvl:;*9jb biweer are there in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) moles k35t ;*oir/xzv2m+ qyprhb s (t)2p boxs+5ay,    $ \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 5sa( :(tcmss(; lgt( pd.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 o6qy n o-:cfs0ef air are in each 2.0-L breath you inhale that were also in the lasfc ne:-6qy0 ost breath Galileo took. [Hint: Assume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translatip 5a(cbyr* c1jonal kinetic energy of an oxygen molecule at STP5c a* 1rbcj(py?    $ \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 neas/.9bju+t88nu za1h1q ibzr y r the surface of the Sun at a temperature of about 6000 Ku8.zrqy/bs iz+ 1b9jh u8atn1 .    m/s

  By what factor will the rms speed of gas molecules inbdq7u bqf 03y)crease if the temperature is increased0qbfdb7q ) yu3 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 followinxsl51*s* p0iy o)k c o/znc+quph:;ung speeds, given in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. +h lu1:zny csq*np cko /0i;ox)s*up5Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at 20.0 -* rkxync2 0iytvn9u 3ehpl5 8$^{\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 h1)(prv*fxm6 ndw*0dz )pwgl keld constant, by what factor do(*dk*)lgmx 0wrv6ndfp 1pzw )es $v_{rms}$ change?   

Show that the rms speed of moleculzs1.v9g6u /p8e nt,6nbh ca aees 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 mixtureyz c.bl)mtz82 of two gases at the same temperature, the ratio of their rms speeds is equal to the inversezmy2ztc8l . b) ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen molecules co(z vwt ;+.wey1df)vy2d. r mgontained 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 speedtvev/o/lb a8n q*9efsa m 7w6* of 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 mkl iank6 j-i4vr4+f ;solecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular masb0798ettu yuijt ): oys is 89 u in a living cell at 3t: y y)80b9iuoj7eutt 7 $^{\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 gam*who q)flx/4 s 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 uranium85 7zw q(-svoltja eud0ma,-a, $^{235}$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 phaseox;t 1n).tu ;o jg erpn7/e,tzm0+ mfrs can $CO_2$ exist? (b) For what range of pressures and temperatures can $CO_2$ be a liquid? Refer to Fig. 13–21.

Water is in which phase when the pressure is 0.01 atm and the temperaturea6o:n5 ufzt* a/zlv 9;.bdymdia96 jn is (a) 90 tlba. :dmuz56va ad *9 in;o 6f9jzyn/$^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity is 50% on a day when the m;/ddj sz00 mm5f m( ,ew7sw.wjjw s1utemperature is 25 mw7 z.jmws ujse;,w 00/dfdjm 5swm1( $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a plac;t/ yepzw/yo/*)oa yle where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in tp.7gf ;d fa(ko; 8gnjrgyqqv y 8i1k:8he mountains is 0.72 atm, estimate the temyrfjg8;7q .( dfyqi 8k8v o:pg1 gkna;perature at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day whir:1yl9lftkh e./ wr))x6 koyul y /y4en the partial pressure of water is 530 Pa and the relative humid6uxlky/ 1.yfk tye:rl49)y/ riol) hwity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the tempekyl1zon;:q t .470-ep6c f yukc/z whfrature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressur.j98 m h4twhzq9bluf5 e inside a pressure cooker if the water is boiling at a te9zw98h5u .lj qbfmht4mperature of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room of volume 68jvgg,l z/x y/b 1r7gc*0$m^3$ at 25 $^{\circ} $ C is 80%, what mass of water can still evaporate from an open pan?    kg

  Air that is at its dew e5dt/u a,phb0xo fn9a lzo(14point 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 mol b (8y-b6coavkecule (see Table 13–4) to diffuse a distance 6by(-caokvb8 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 sur-xe h-4 2m4/*ird rfnghh fzxjm n.u//face of insects to the interior through tiny tubes called tracheae. An averageg4 hn m-z xrn4ihjfm/rhx2. -/ d*f/eu trachea is about 2 mm long and has cross-sectional area of $ 2\times10^{-9 } m^2$ Assuming the concentration of oxygen inside is half what it is outside in the atmosphere,
(a) show that the concentration of oxygen in the air (assume 21% is oxygen) at 20$^{\circ} $ C is about 8.7 mol/$m^3$ then $\approx$    mol/$m^3$(Round to one decimal places)
(b) calculate the diffusion rate J,    $ \times10^{-11 }$ mol/s
(c) estimate the average time for a molecule to diffuse in. Assume the diffusion constant is $ 1\times10^{-5 } m^2/s$    s

  A precise steel tape measure has been calibrated at 2r)ijfcrqm4 16 0$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A precise steel tape measure has been calibrated atqxyei+ns+lf82c6h.n2zp+0y ii i+m n 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 noroigdf,;c 8pt /-i3kz td)fv7r mal room temperature. How much error will be made in a recipe calling for 300 mL of cool ic rtzd/v pogd )k;f7ift, -83water, if the water and the cup are hot, at 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in a helium gas cylinder is initially 28 atm. After many b(bm-2iog c v*ojp1t )oalloons have been *vc1ibjomg-o )tpo 2(blown up, the gauge pressure has decreased to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air mot)yyn, mn r),xlecules in a room of length 6.5 m, width 3.1 m, and height 2.5 m. Assume the temperat), ym,n txyn)rure is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is about one atomt,;:raza+ - q,mxpv0uphl; u p per $cm^3$ mainly hydrogen atoms, and the temperature is about 2.7 K. Calculate the rms speed of these hydrogen atoms, and the pressure (in atmospheres).$v_{rms}$ =    m/s    $ \times10^{-22 }$ atm

  The lowest pressure attainable using the best available vacuum techniques is ab xg9ngofknaxx8fdn(wi pojz) j-.- 1yi *43d-oudz-j-9n.3 ij4 f xx- opkw(ynad xo8*i 1ngf)gt $10^{-12} N/m^2$ 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)gebla5b9kk*u+d 0c a .5 L when 10 m below the surface, to what volume would his lungs expand i0aucb+glk 5e *)abdk9 f he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moon eiw k ,0wj+e7a.jsom6izu1 d3snters Earth’s atmosphere at a speed of about j .6d3u0az, jwsi 7emwi+kso140,000 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 reentry.)    K

  The temperature of an ideal gas is increased from 1;*)v: y j,j/ukauk.e;yt blsh10$^{\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 770m;:g* ae btk2if$^2$ (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, estxszc o47,)u jpimate the total number of air molecules in the Earth’s atx oz4 7jc,)supmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecwnm cc4rt4we *w*rbjno 7c,2+ ules 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 use1hdxb1 t-:-ecw +tcfvd in a hospital has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmospherd1fx -t:etb1+- vcw hcic pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liquid;b3s akq, 1ros 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 gasoli9kq7aj p3u2as ua6m*cne 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’0)srbit r23v; kkc4hcdx;+81va l kxy 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 tig+9j* a(-x8ia ut quyfihtly 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 sta5kb5fo kgx z1q* c0 pr.:lft4yndard, 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 atkf8dkrwh, +7v xbqb05)( b8gv rfu ci8m 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 Earth is:x,t 9 dew:nokhd ;x7j $ 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 gravit(xzsm /neu0x gytp; 6o2 we*,;hqfl*oy by tennis balls thrown vertically upward at it. How many tennis balls per second must rebound from the lid elxn w*/e, (um;y*hogf o t2q6pzxe0l;sastically, 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 from a dep m+s.tnl2gwm(*vj/co9r x.e lth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the air behaves as tlre 2(v gwns+..ojx9m/lm c *a perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure i 3kosjm0f8z.m q0 nlw:n the air on the following two days: :wolskmf 00mnq. z83j
(a) a hot summer day, with the temperature 30$^{\circ} $C and the relative humidity at 40%;    Pa
(b) a cold winter day, with the temperature 5$^{\circ} $C and the relative humidity at 80%.    Pa

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

  Estimate the percent difference in the density of iron at STP, and wh13hz7vbrbe 6q; 9mfb wn6wt :qen it is a solid deep in the Earth where qe w1;v9bmfwb r:tz7b3h q6n6the 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 vgl xg/dknoaw6 6i*+0that, for an ideal gas at constant pressure, the coefficient of volume expansion is equal tkwli0+vg / go*dnax66 o $\beta$ = 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.