Which has more atoms: 1 kg of iron or 1 kg of aluminum? Sesp9 vwr6 ef44pe the periodic table or4v9sefpr4pw6 Appendix B.

Name several propertiyw5uc f74+mzqyqz4aw( -ao3 oes of materials that could be exploited to make a thermometew5y c+ua47yao3 oq zfw4- mzq(r.

Which is larger, 1 C w ;p2 7;tzu9te n1nftb$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with syst 2z .eujhh4i(0xml1wmrwlk3vj 4 - o9cem B, but B is not in thermal equilibrium with system C, what can you say about the temperatures of Azrhjwk ilo.2w(cv10ml 9ue4mx 4-h 3j, B, and C?

A flat bimetallic strip consists of aluminum rikbpdk-g: b.rs,iy2me 4rmz * ap(g7+e veted to a strip of iron. When heated, the strip will bend. Whichrg *be.s, y27pk:ikgp- mm+arb4z( ed 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 coefficient of linear eh dtgkn ):z5/cxpansion $\alpha$ 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 thermostae,5wuhd qn)c8t used to control a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch is a glass vessel containing liquid mercury that conducts electricity when it can flow to touch both contact wires. Explain how this device c duheqc8,n)5 wontrols the furnace and how it can be set at different temperatures.

Long steam pipes that are fip 5eyiiu0t-vbf.)m: ixed at the ends often have a section in the shape of a U. Why0t:b -y p.ivimife)u5 ?

A flat, uniform cylinder of lead floats in mercury at xu .vrsgs,1f* 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass a e y -thjmjfjw6+3r16f,/ duqthermometer is first placed in a hot tub of water, themajqe t3ju1 rf6wf6h/ +ydj- , mercury initially descends a bit and then rises. Explain.

A glass container may break if 4 9 co95bfv8q )xghj +v+idl +sgk,rqcone part of it is heated or cooled more rapidly thahrbc fsvo g+gjqd94 +,+8lc9xikq5 v) n adjacent parts. Explain.

The principal virtue of Pyrex glass is that its coefficient of linear e7d*h6c , aiggvxpansion is much smaller than that for ordinary glass (Table 13–1). Explain7v*c6ag hdi g, why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurat4 ogdw5 jf0/4sks9qtle at 20 $^{\circ} $ C, run fast or slow on a hot day (30 $^{\circ} $ C)? Explain. The clock uses a pendulum supported on a long, thin brass rod.

Freezing a can of soda will cause its bottom and top to bulge so badly the )e6 n: tvxa7i:n)d-c 2 grjocican will not stand up. 67 r)gvd::n niatiexjo c )-2cWhat has happened?

When a gas is rapidly compressed (sobscy)f :. 7nvr s9 anm+jg+xxu* *r-way, by pushing down a piston), its temperature increases. When a nw- y7)ags.fvsxonj*9+ r cb+mu*xr :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.

Will the buoyant force on an aluminum sphere submerged ind;6i 1 /zbi jrhhaakg3:6 9ony water increase or decrease if the temperature isyaakh ndh/b36 r zoj9:1i ig6; increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theory cavn z2+.-q apand the relation between average kinetic energy and the abs qc2a+ avp-.znolute temperature.

Explain in words how Gay-Lussac’s law fgg . z .ysfup..x/qy,yollows from kinetic theory.

As you go higher in the Eun:z 43fhgznhr ::- dc-)vtpbarth’s atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Eart,g88f+vrl k e.1t6l5gy )cswbb rlnl9h refers to the minimum speed an object must have to leave the Earc8,lk ft+ 6r.5s9b8 en)yw bl vrlgl1gth and never return. The escape velocity for the Moon is about one-fifth what it is for the Earth due to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates morz0fkys c:sav/+)ag p+o1o wz;e quickly than water at room temperature. What can you infer about the molecular properties of o/p0vks ;gyc+wza :o+sf) 1 zaone relative to the other?

Explain why a hot humid day is far more uncomfortable than a 7m s-voet)no.hot dry day at the same tee) 7m. oo-stnvmperature.

Is it possible to boil water at room temperature (20q;)c dd69ebjqy 9dzun 9(a ;zz $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the5) biq;li4u rh humidity is different. Which is more dense, the dry aii5ri u)b;hq4l r or the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap of an overheate8/qa+q*; 1a,poiobsv )tswe od automobilesq;q/v+o) s1,bai* oa8o wp et engine.

Why does exhaled air appear as+2is p;w 64 3l4 t1n*6veotkbsnrmf lx a little white cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram copper penn (kjqhnz nni*8q w.:(sy?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold riy;7ot jn9 so*wv0ic)) xo i ea0-c/jwung compare to the number in a silver ring of ec;ios) jx j9/ct-*0o)0n7uwwov iya the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. Whatv qxovj3n 6-2s is this on the Celsius scale? vn x26ojs3-qv   $^{\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 temperatures recorded are 136r 0a v a p5c)d,9kjzp,kzx01t:be5wel $^{\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 thermomem,(lffazz602 (a uxdd8kh5f3hor5in ter, the alcohol column has length 11.82 cm at 0.0 3xur86(d5 f0oa2fifm z 5h nkhl dz,(a$^{\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 y1uyqve oo(6qbc k9c)u9f,6 w)w2m kpbuilt of slabs 12 m long (20 $^{\circ} $ C). How wide should the expansion cracks between the slabs be (at 20 $^{\circ} $ C) to prevent buckling if the range of temperature is -30 $^{\circ} $ C to +50 $^{\circ} $ C?    m

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

  The Eiffel Tower (Fig. 13–29) is built of wrought iron bmsp7+4 cyd4iy,r s1eapproximately 300 m tall. Estimate how much its height changes between July (averagys pmeyr 4+7c41s,bdie 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.nw nhr6r3r+jq;u yu, that are larger than the rivet hole are often used and the rivet is cooled (usually in dry ice) before it is placed in the hole. A 6u r3,jrq+;hwnr.y n usteel 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 gow 9ujy0g;o)of g va5w6dk pr./. hc*at 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 i4t3b5qm5fhz dl/h 2 aun diameter. What will be its change in volume if it is heated fr4/afzdhm25bu hq5 tl3 om 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 a8esxl t2d6tz2t 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.j1oy x5 u--htonih9*+pof gi650 mL of water at 20 $^{\circ} $ C completely fills a container to the brim. When the container and the water are heated to 60 $^{\circ} $ C, 0.35 g of water is lost. (a) What is the coefficient of volume expansion of the container?    $ \times10^{-5 }$ /$C^0$(b) What is the most likely material of the container? The density of water at 60°C is 0.98324g/ml.

  (a) A brass plug is to be placed in a ring made of m:/pw kcn5dj44kv fttp 65bz;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 v ed2ro/5lt9a ressel so it can expand in essentially one direction only, show that the effective coefficient t5a orr29/edlof linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the density h 5k4mvqvt,i;aq; jt2j1 ,v67y mvptb$\rho$ 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 coefw f67y; on0ba*bjwx: lficient of linear expans;xl:ab*0wwj76y o bnf ion $\alpha$ 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 so.ztce siv;ruv x+kw*x42cz 3 y5f 8ls6lid, $\beta$ = 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 time ati/(ccyyb h7z) 1/ zi7y (ybcch)7 $^{\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 thermomet+ 74w)pd 6t cgxxw/fljer has an inside diameter of 0.140 mm. The bulb has a volume of f7/pj xdcwl64g+)wtx0.255 $cm^3$ 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 cylin/) ozia/p-jj,y8qgf: pi 6hdgdrical wheel of radius 0.41 m is rotating about its axle on frictionless bearings with angular,i p /pfh-idag og)6zq8 /jy:j 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 lxnzfz);**z*n jk/x l9 mrjhm0ength when at 15°C. How much stress is required to keepn zfh0jxz ;*)mz*k9 j m/n*lxr it at this length if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-sectinw8e ote9se 87onal 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 diameterdds+(; o 8rnr jiw7a+w 134.122 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 temperatures on theiopj hj.b,.)e Kelvin scale:
(a) 86$^{\circ} $ C,    K
(b) 78$^{\circ} $F,    K
(c) -100$^{\circ} $C    K
(d) 5500°C,    K
(e) -459$^{\circ} $F    K

  Absolute zero is what temperature on the Fahrenhea t2 ne3t(lvtx0 b/oz*it scale?    $^{\circ} $ F

  Typical temperatures inf0mn 3mxjr+ )n the interior of the Earth and Sun are about 4000$^{\circ} $ C and $ \times10^{6 }$ $^{\circ} $ C respectively.
(a) What are these temperatures in kelvins?    K    $ \times10^{ 6}$K
(b) What percent error is made in each case if a person forgets to change $^{\circ} $ C to K? $\approx$    %(Round to the nearest integer) $\approx$    %(Round to three decimal places)

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

  In an internal combustio90z-m do jeaw0nmc1f2l8.ddt n engine, air at atmospheric pressure and a temperature of about 20-0d1 f 9nzmod0 ctw8d2ma.ejl$^{\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 awv.v5b ,df hr /2kk*+xadq55d(0lb m n-ufjkxt STP using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg ofbzvy0uusd+ *j5b gz07 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 qsh8x0+3uhz u contains 18.5 kg of nitrogen ($N_2$)
(a) What is the volume of the tank? $\approx$   $m^3$(“Round to one decimal places)
(b) What is the pressure if an additional 15.0 kg of nitrogen is added without changing the temperature?    $ \times10^{5 }$Pa    atm

  If 18.75 mol of helium gas*;o.q3ou .fy gfgm omijf)ke 35rye81 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 insid +-k :1cjo*fghpk z9j rb82hpye a 35.0-L container holding 105.0 kg of argon gas at 3kcp bz+81p2hfo :9jhrykg*-j 85 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg of :e-u;vk opjv-w3*rzg $O_2$ 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 sof 0v 82an)roby heating the air inside the balloon, which makes it less dense than the air outside. Supposf8r0van o s2)oe 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 at 9c:5jl1 edl72nbccfl 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 x k*dj)v*n ;he0y h7bsat 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 escapes a c mqp jfr34qs/m c)+k8 u33gfezhild’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 molecule,i;j dj )wxg7m*.d7)xfo gabm s / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 nxh6e vw f/*9gL? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) yr 3di54fnh*kmoles,    $ \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 volumey0k,iro+r +v c 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 fv* * m)27cyg5ku wldnair are in each 2.0-L breath you inhale that were also in the last breath Galileo took. [Hint: Assume the atmosphere is about 10 km high and of constant dyvncuwg* m*dlk 72)f5ensity.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energyzfjyj : .;skc2k*v( ew of an oxygen molecule at STP:k k( 2v*w yfzjs.cj;e?    $ \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./h ptfhe7a-3dky4+ a( bd sva surface of the Sun at a temperature of about 6000 K. apt3-hd /a+7 (sh bdfvk.e y4a   m/s

  By what factor will the rms speed of gas molecules increase if the temperaturd) ,ukx*db t49a kkc4pe is increased fpc9bd4x *kt kdu4a)k,rom 0 $^{\circ} $ C to 100 $^{\circ} $ C?   

  A gas is at 20 $^{\circ} $ C. To what temperature must it be raised to double the rms speed of its molecules?    $^{\circ} $ C

  Twelve molecules have the following speeds, given in units of km/s: 6, 2, 4,)vxvyy5j/cv k wb o-0*nsp3+i 6, 0, 4, 1, 8, 5, 3, 7, and 8. Cal5ip-/n3bskvx*0c w y+jy vvo)culate the rms speed. $v_{rms}$ =    km/s

  The rms speed of moleo+*djb y d4,chmi0-b. 1bz;dftlyk 8ucules in a gas at 20.0 $^{\circ} $ C is to be increased by 1.0%. To what temperature must it be raised?    $^{\circ} $ C

  If the pressure of a g-wu kkpz. hu;m2q8fwe/s+9ge as is doubled while its volume is held constant, by what factor 98 kw.zgeem w-/phu2k;uf+qs does $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is given 9 y6n ki6zeu+yby $v_{rms}$ = $\sqrt{3P\\rho}$ 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 tet: zs5bl ;k ;wgnii,5nmperature, the ratio of their rms speeds is ,ib 5:5gkwiz s;l;ntnequal to the inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen molecules c rhqp coo f1ov;,57gs9o+ zzixbn ;a07ontained in an 8.5$-m^3$ volume at 2.1 atm if the total amount of nitrogen is 1300 mol?    m/s

  Calculate (a) the rms speed of an oxygen moleculp iv)3qhpx4d 2e 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 qa(4 0wum4kj,mkp 7 mlmolecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular mass is 89m;-74u2tun* d(q7qz6pf 4rjxf xi qxn u in a liv m7; jp2nu-(rq4xx4qi7td zf*6qfux ning cell at 37 $^{\circ} $ C.    m/s
(b) What would be the rms speed of a protein of molecular mass 50,000 u at 37 $^{\circ} $ C?    m/s

Show that the pressure P of a gas can be i zgi0zc7ru(6 axv7z: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 uraniwscz+w kbc( q,x;,5yb6,l ieg.k:oot um, $^{235}$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 phases canxg49)l1)hlp1 s fdwddl 6x( jp $CO_2$ 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 batj,m(dl 5mm 5*u1oh the temperature is (a)jod(lam1umb 5m th ,*5 90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the iek p*mm8;3zfv7y/dt humidity is 50% on a day when the temper;p vkz*7md3t /i m8efyature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a plu3)u z6g6 k yyovw9u5m pb-c)idi aj25ace where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is 0.72 atm, estimyglk a g*s:q 8gv* oe8)j4o:ojate the temperature at which water boils.*vq og)gyl *8ja8 jk:ego :4so $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when th 6,eq-pj 8yomae partial pressure of water is 530 Pa and the relative humidity is jyea-86mpq,o40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when xb; 5 h rnjf/an:*xz9mthe 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 i6iy+gfgb, v 3whn5o+ zwx 4l(boiling at a t3n4x6ovw ,b+gwh5 l +izigf y(emperature 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 oosq(;i tmxsmo e*z*1fc ap):.f 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 drqd1s70raf.t:a/ ta/kd e*mu x zeul27 )z-nq ew 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 Table 13–4) w,ra3 w9,xmyy to diffuse a dist,xry3mw w a9,yance 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 i 0cxj3q y5x,5 l,ntffgnsects to the interior through tiny tubes called tracheae. An average trachea is about 2 mm long and has cross-sectiyc ,gjn535fx0, qtxlfonal 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 bi/;8shi yitey). -zcgeen calibrated at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A precise steel tape measure has been ca7dopvw y9w:y8 tsf8x7zh 2 bs3librated 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 temperajwpx6h9a x5.eture. How much error will be made in a recipe call5 x p9a.exj6whing for 300 mL 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 gas cylinder is initially 28 atm. After t*8r( m-y:yv6sretefmany balloons haveyr mv t-etf6*e 8:r(ys been 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 molecules itke.ux0 u2u-3lmk 6knn a room of length 6.5 m, width 3.1 m, and 2ueuk. 0l nmk3u kt-x6height 2.5 m. Assume the temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is about one atom pern/ 8 9 i9u5gxznkmnbbr 0/6m*pl gxmg. $cm^3$ 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 83s so+ulk n7dusing the best available vacuum techniques is about 873n+uslksod $10^{-12} N/m^2$ 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 b,dp v)x;j(eg yelow the surface, to what volume would his lungs expand if he quickly rose to the surfac x(,e)y jpvd;ge? Is this advisable?    L

  A space vehicle returning from d*qvk :m5/n ssthe Moon enters Earth’s atmosphere at a speed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this speed correspond to what temperature? (Because of this high 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 reentryd:ssn k* /v5qm.)    K

  The temperature of an ideal gas is increased from t c-l:z./qr fakl/r6i 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 ofadene) ;r qez )q + 9a/rai(i5c6v.sof 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 * l,x itvgpz85(zr :goof atmospheric pressure at the surface of the Earth, estimate the :rz vgzlpig(*, x8 t5ototal number of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contained in a 7.6q:)4 j ed*ns-iusxp3 n*k d8ye$-m^3$ volume at 4.2 atm if the total amount of nitrogen is 1800 mol?    m/s

  A standard cylinder of oxjnc-r-8uzol, a6dc ;qygen used in a hospital has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measure6,nro cq - z8ldj-;aucd at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of ,3p b3vjjd3 lhzqmb7+ liquid mercury at 0$^{\circ} $C. (a) If the temperature is raised to 25$^{\circ} $C, will the cube float higher or lower in the mercury? ----待选择----lowerheigher 
(b) By what percent will the fraction of volume submerged change?    %

  The density of gasoline nw5khc// e t5nat 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 l()xr*2rz ecy60vbr +aotc e3equator at 25$^{\circ} $C, but then was heated to 45$^{\circ} $C, how high above the Earth would the band be (assume equal everywhere)?    m

  A brass lid screws tightly onto a glass jar avkc q19: 1gpwot 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, adopted in thtb ,purx ,m ho4:2a)ite 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 chard.3 wc+r mth)+u r1djtd-9uwzged, has a pressure of 195 atm at 20$^{\circ} $C. The volume of the tank is 11.3 L.
(a) What would the volume of the air be at 1.00 atm and at the same temperature?    L
(b) Before entering the water, a person consumes 2.0 L of air in each breath, and breathes 12 times a minute. At this rate, how long would the tank last?    min
(c) At a depth of 20.0 m of sea water and temperature of 10$^{\circ} $C, how long would the same tank last assuming the breathing rate does not change?    min

  The escape speed from the Earth i rldk zxf0ucsk,.1 x6y7tif 5i)1rg8vs $ 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 emt5x 32y7v6,bzf6 twy9e b kois suspended against gravity by tennis balls thrown vertically upward at itbov fm76 93w62 5txyk,zebyet. 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 (sphericaqru(2h gd-bvieib(z (bd- ; /yl) 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. Howeb;/r(u(vdqb b ihi- zd(g 2y- large is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure in the air on tjz yk.fb ir)iy p;/;x/kou+ 0she following two days: y.up;z x0y+/k;oi rbj/fi )ks
(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 m0l p+gkfwn7*o8s;rz STP, and when it is a solid deep in toz8r+lgkw0 *pn ;f7mshe 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 ,r 6ncd7wmpm ;gas at constant pressure, the coefficient of volume expan6w7mcm nrpd,; sion 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 prev)dgajh(anb .vk -bry70lwawz/bmg689 2v p 8rent rot and mildew. If thb8 k) l7a6gy w9wb2 jnarm/a-z8v0v ( dgphr.be 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