Which has more atoms: 1 kg of iron or 1 z8n,7/ 1p9bymugc t 3hak:p drkg of aluminum? See the periodic table ort:8u3pnhbd g9 7 cza,ympr1k/ Appendix B.

Name several properties of materials that could be exploited0o-2hn9mn(6 bnw ot96 qmsimbq3uz8w to make a thermometer.9iuo03qt9n nzsq wb28mw-(ob66 nmm h

Which is larger, 1 Cbhe atk-g +t-1 $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B is not in thermal iqy+ql-l2x2 jequilibrium with system C, wj2+xq2yq l li-hat can you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum rivetw ek33tk;8khigo91e jt+o+b bed to a strip of iron. When heated, the strip will bend. Which metal will be on the outside of the curve? [Hint: See Table hibj+to3 ek9o;ewk 8k 3t+b1g13–1.] 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 linea6 llsz45c1b2l2zkbxmt 2 na7jxd/h a 2r 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 itk7nn9i zv;j( gh5-ddiagram of a simple thermostat used to control a furnace (or other heating or cooling system). The bimetallic si(itdvzhjn; 5gk n-79 trip 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 controls the furnace and how it can be set at different temperatures.

Long steam pipes that arq ii- t 2ypstb15v8kh/e fixed at the ends often have a section in the shape ofq/18ii5 tbt2hpys - kv a U. Why?

A flat, uniform cylinder ofok7s5dzo hh7/ 4uf .x)a onn4u 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 thermometer3o8wju ndo7cjg8 c l95 is first placed in a hot tub of water, the mercury initially descends a 3jc9c g5unjlo7 8wd8o bit and then rises. Explain.

A glass container may break if one part of it is heated or cooleaf mtag/ )bu,tn)c:q -d more rapidly than adjacent parts.t,c )nm aqt:a)/gb- fu Explain.

The principal virtue of Pyrex glass ikjm6xo, o lhf(1*/k1l)kn b qis that its coefficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat res6li*njo/fobhmx, (k1q k k)1 listance of Pyrex.

Will a grandfather clcsjws6p/b xjxk 18.r)dzk93;yk b )r kock, accurate 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 c tyazds3 :;pb*gsbv-v*i5s ; ban will not stand up. What has 3ivgdsat svsbyb-* *pb:;z5;happened?

When a gas is rapidly compressed (say, by pushing down a phrf d6cug).j 8iston), its temperature incgdju8rfc .h6) reases. 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.

Will the buoyant force on an aluminum sphere tinaqw,2 4 ox l;0p zrl,69amzsubmerged in water increase or decrease if the temperature is increas 2na x 90qw;lrzoam46ptl,iz,ed from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follow,4.kzf 1paz lrhwdvi ztwnv:zy3.8/)s from kinetic theory and the relation between average kinetic energy and the absolute t zik3v. ,/zzn)z1:hrf4vw td ylpa8w.emperature.

Explain in words how Gay-Lussac’s law f37nlkz5c )sil ry en v:t.b18kollows from kinetic theory.

As you go higher in the Earth’s atmosphere, w8(di e wm,b6sthe ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the mim un j4n/u/fz,nimum speed an object must have to leave the Earth and never return. The escape velocitz jm/u,n/n f4uy for the Moon is about one-fifth what it is for the Earth due to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly thazl7( 3ifsv9g gn water at room temperature. What can you infer about the molecular prope39if7s(gvgl zrties of one relative to the other?

Explain why a hot humid day is far more uncomfortable than a hot dry dat9n+/6 upjb,3qv0;t ubme ;s mtyh1zu y at the same tej,s ;pyu;z 1 69tmvt q+0et/3uubnbmh mperature.

Is it possible to boil water at ndk(;nm i1w- zroom temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the (vq756hxida022 tj 67jf lg6 jg- xlw4xog oigsame but the humidity is different. Which is more dense, the dry air or the humid air at ti j6q5 o 2j x0g7x47hjog2 wt-l6a6 vxgldgi(fhe same T? Explain.

Explain why it is dangerous to open the radiator cap oc+djdg* 8-nt wf an overheated automobile en cg8w+*d-djn tgine.

Why does exhaled air appear as a little white cloud in the winte9- pbljhwift:4 b/gd5 tr9+ujr (Fig. 13–28)?

  How many atoms are there in a 3.4-gr2j5(gtflh 9 ai jjo,3pam copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring comparlkdm2:s8d zdjkc7 jac0 g b97)e to the number in a silver ring of tzd)mcgl: j 9k2c0d 77bd8ajks he same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this on the Celsius scalggyg r.t ls85*e?s*8ygg .5gl tr   $^{\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 rec,rj uv,0l3wi vorded 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 alcoh f -q5q4wl95-7p gijyk(mlhvool column has length 11.82 cm at 0.0h 97y p4-l5jqf l5oi(wkm-v qg $^{\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 1pgws8m4b f/jem;2fko tj2 t5(w 8 o;xz2 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. 13–29q7s (0ul1v hty) is built of wrought iron approximately 300 m tall. Estimate how much its height changes between July (average temperature of 25°C) and Jtyql v 10uhs(7anuary (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 ymik* +f78zuq 8u9gmfthan the rivet 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 1.8ufgi mu k9z88 f7*qmy+69 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 ytx47unzh o(eqoc/wgy* b -.7 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 in diameter. What will be its chang6tdvw+zg7pf ftfx7 7h o5m,w)e in volume if it is heated from 3 wd)ftm 756ovpf ,x7wg+h7t fz0 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filljss,*n: wg40g x)dwgeed to 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 m3pwt rtd9/ckl7a8-y ;uyn,np L 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 bsz,gdh2nh,7l 75vpn be placed in 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 in8wsaveq4u lu y(pck* 6+ pu9-w essentially one direction only, show that the effective coefficient of linear expansion is approximately eqs9l6pu k ea(*p4wyuc+wu-q v 8ual to the coefficient of volume expansion $\beta$.

(a) Show that the change in the densica0md( s00kcjb t oh11ty $\rho$ 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 coek 0bs.zb24hcy oj7e bkggc9 7(fficient of linear expan7gy jheb92k(z c g.bsc k70bo4sion $\alpha$ 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 isotrop:f tx /n//ycwoic solid, $\beta$ = 3$\alpha$ if the amount of expansion is small. $\beta$ and $\alpha$ are the coefficients of volume and linear expansion, respectively. [Hint: Consider a cubical solid, and neglect very small quantities. See also Problem 18 and Fig. 13–30.]

  The pendulum in a grandfather clock is made of brass and keeps perfect time aji8 + 51ychlszt 1y1ic5sj8 hzl+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 mercurqed xluhc ;rc+ca, qr4+-dr,;htf9c9y thermometer has an inside diameter of 0.140 mm. The bulrdr t+4xf+h,;rca ;qc dcce, lhq9u-9 b has 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 rryl0c,9s+qm;h*; bcd lh-zw y adius 0.41 m is rotating about its axle on frictionless bearings with angular -r b* 9hyzlmdl;hwc+y c,0q;svelocity $\omega$ = 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 wh )a4z *zhgm -av;qj6gzen at 15°C. How much stress is required to keep it at this z-; *h q6gagm4 )zjazvlength if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steeq2*saee+0a aiekqx.4 s - xwwx9x.g8g l I-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 134.15)qw o)jx:;lbnxn3 jo22 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 temperatuy3yh9d8 pqp3ql gj. :lres on the Kelvin scale:
(a) 86$^{\circ} $ C,    K
(b) 78$^{\circ} $F,    K
(c) -100$^{\circ} $C    K
(d) 5500°C,    K
(e) -459$^{\circ} $F    K

  Absolute zero is what temperature on the 42eah ks-wxot51rh g(Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior offx rj80tw*0 vjgo/:vv 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 pressub4lnsah(9 er7re and a temperature of about 4lsre(nab h7920$^{\circ} $C is compressed in the cylinder by a piston to $\frac{1}{9}$ of its original volume (compression ratio = 9.0). Estimate the temperature of the compressed air, assuming the pressure reaches 40 atm.    $^{\circ} $ C

  Calculate the density of oxygen at STP using the ideal x q9*c1*4fcjg)v ae wmgas law.    kg/$m^3$

  A storage tank containst qm2/zgei35r ;t1sbe l8a 5hq c+-lrf 21.6 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 contf9v yv5w ,. vo3+ud yea53dwjgains 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 is at 10 1phd9a*h6ei j;:shzz.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 of argon gas4oj lw e +*m4tks5x gpw;vm3y* at 385 K vpx*kmlww mg4 ;ojyes*3+t 54?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg of ag10 l1 q5b e+4o dyd8njnq:ah$O_2$ 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 achievesb (qqy,qh8iixr2kk (. its buoyant lift by heating the air inside the balloon, which makes it less dense than the ai( y bhix(k8 qi.qqk2,rr 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;+, xw0cr d5djj ytx-y air 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 18./ ( i(hrtfl* ht:ixw0v0 $^{\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 balloonq4, ml+ sn,wnm escapes a child’s hand at sea level and 20.0 $^{\circ} $ C. When it reaches an altitude of 3000 m, where the temperature is 5.0 $^{\circ} $ C and the pressure is only 0.70 atm, how will its volume compare to that at sea level?    times the original volume

  Calculate the number of molecfpy w4w,xgvygv: (9j ,ules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of wat0. .p3 6vrtx6pkbg h3k8cxp yxer are there in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) molkz* dlf6i*fsqz1j6 z ,es,    $ \times10^{22 }$ moles and (b) molecules of water in all the Earth’s oceans. Assume water covers 75% of the Earth to an average depth of 3 km. $\approx$    $ \times10^{46 }$ molecules

  A cubic box of volume 5.1f r9se(v f2t8b$ \times10^{ -2}m^3$ is filled with air at atmospheric pressure at 20 $^{\circ} $ C. The box is closed and heated to 180 $^{\circ} $ C. What is the net force on each side of the box?    N

  Estimate how many molecules of air are in each 2.0-L breath you inhale tm ,uprdg8 .331abww ashat were also in the last breath Galileo took. [b m13, wpa d8asur3.gwHint: Assume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translati6qun:1 yhag sur p:xm7(5d4w ponal kinetic energy of an oxygen molecule at STP?pu: d:4hpsu7ygnxra 6w 1mq(5    $ \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 at a temperayw7gz:i4b7y o.ee e+sture of abog7eo 4z7y bey+: sewi.ut 6000 K.    m/s

  By what factor will the rms speed of gas molecules inc wrm b8l,,lzi1rease if the temperature is increasebw rzm8 ,l1il,d 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 mn-s7g8auo4*k wu h;ein units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3,8ghu;*w o nuke4s m7-a 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a ;wy3 aj)35e ,w ; stjgwxaxf(ugas at 20.0 $^{\circ} $ C is to be increased by 1.0%. To what temperature must it be raised?    $^{\circ} $ C

  If the pressure of a gas is doubled while i23tpbfs v16ru ts volume is held constant, by what factor do ptbusf26vr31 es $v_{rms}$ change?   

Show that the rms speed of molecul b-v6vur m/z(pes in a gas is given by $v_{rms}$ = $\sqrt{3P\\rho}$ where P is the pressure in the gas, and $\rho$ is the gas density.

Show that for a mixture of two gases at the same temperature,5dbi1r p(/ 9hc ao0dh0 tjbvn: the ratio of their rms:(1bn odacdt0h ijrb59v0/ph speeds is equal to the inverse ratio of the square roots of their molecular masses.

  What is the rms speed ofo4jt2w ij(cky 9i1 my ila-+m: nitrogen 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 oxygen mq:-u2 lfu1cj kolecule 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 molece -ym hwmd2s 6/.ql8tsules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms z9+yhm 3wfdj49 r +s kg(ea5tvspeed of an amino acid whose molecular mass is 89 u in a living cel+3dr9f5v zymh js (ag 9w+4tekl 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 c zp ef1o-se0 1*b5ftc p)w7uucan 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 pl;l0y+hko1d uranium, $^{235}$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, * da9)xpmqf;s-utoo8in what phases can $CO_2$ exist? (b) For what range of pressures and temperatures can $CO_2$ be a liquid? Refer to Fig. 13–21.

Water is in which phase when the pressure is 0.01 atm and the tempetmzfd 9s(id 6r1 6j)kirature is (a)6jirti) kdm 6(s91zfd 90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidityv62k5 8n v*jizb3ue b/sht j;c is 50% on a day when the temperatzn8 j*kh5uvbes6tb c3 i;2jv/ure is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water b:fnf7ou e8ih s- 8gm3joils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure :,3/sfvf) upfkg0ntlh ;e)yx at a particular place in the mountains is 0.72 atm, estimate the temperat:g np) u 0)sk fvxf3ft;hy/,leure at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of water is 53lyn 1ylj (2di3swd 8bg47 lu4 x6alja60 Pa and the relative humiu ij6sjw14l7 d a6dlyx8l4y2 bla(g3ndity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a daszlblqoqx*r)a867jp56 vy(m y when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure insjmd85f9nx- bdg +kw1uoia: r5ide a pressure cooker if the water is boiling 15i9: fj8kdnw ao bu gm+5xr-dat a temperature of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room ou7;rhr oj5y r 0.cihj*ci. +qqf 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 dew poihe*prmhtyjy+ w7i - +/nt 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) to diffuse hs: b ziuv;:8 s9v6rmia distance of 15r : ss8v:;ivh6uimz9 b $\mu m$ 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 fromxu4g9i 42jawu-:l99m 9vcme pcg4zto the surface of insects to the interior through tiny tubes called tracheae. An average trachea is about 2 mm long and has crwl tm2ip e9zgg 4ua-9c o4xm4ju9:cv 9oss-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 2k-cttvb/; y:t1gi g(o0$^{\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 meo lcbz ,u 8k6ifnj()2,jott w+asure has been calibrated at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A Pyrex measuring cup was calibrated at normal room temperatureiu il0;,moe: *timv4x. How much error will be made in a recipe calling for 300 mL of cool water, if the water and the cup are hto,vii 0 4 mmx:;uil*eot, 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. 2:t8hghewlk y5s 7.ouAfter many balloons have been blown up, t gks:.h7he ou528ltywhe gauge pressure has decreased to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air molecules vd3z xi:y:gvcc /1l+ win a room of length 6.5 m, width 3.1 m, and height 2.5 m. Assume the temperyi: cz/vdwlc3xv+ 1: gature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the dens-t(sglnyu ;p(j 4x h,iity of matter is about one atom per $cm^3$ mainly hydrogen atoms, and the temperature is about 2.7 K. Calculate the rms speed of these hydrogen atoms, and the pressure (in atmospheres).$v_{rms}$ =    m/s    $ \times10^{-22 }$ atm

  The lowest pressure attainable using the b5rj7cqrq4 ra xr1k f4s14ew(lfw,rf 9 est available vacuum techniques is about j,( lq9 74f wkx51fqr4raecrwf 1rr s4$10^{-12} N/m^2$ 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 capa :ejud xu3tr+:city of 5.5 L when 10 m below the surfu t+: :jue3xrdace, to what volume would his lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Mo2v y-s) w7hbarqe1g0v on 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? (Becausvy0 v2) wrh1s7-a egbqe 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 ix edgv4 dad--; 9x eheh5 h/.pk77usuancreased 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 770 lu ))eolz -j )k2ou km0.idq-dtztg0-m$^2$ (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/ hybbwsczd /r/9d ;(e Earth, estimate the total number of;r(c/bdydhs /9zeb /w air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contained in a 7.6 w 1ps; a sg666s-**loob(lzmvazmq;fd x4h2f$-m^3$ volume at 4.2 atm if the total amount of nitrogen is 1800 mol?    m/s

  A standard cylinder of oxygen used in a hospital has gauge pre7w2f r 7q *f((;tyclukj/- k ,u; zoawgzmc6fossure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure, is zo;6/ oau7wrulf,(qgfj 7*w2f m;y cktz -c(kconstant at 2.4 L/min. $\approx$    hour

  An iron cube floats 3hj7fd /d) zjx3ujmr) in a bowl of 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 at lpf lfib7:kgc3:lzt u- :z2w 2geh7m00$^{\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 arou/l96ff8 py-twy) u;qkg9.o v tsb 5pwmnd the Earth’s equator at 25$^{\circ} $C, but then was heated to 45$^{\circ} $C, how high above the Earth would the band be (assume equal everywhere)?    m

  A brass lid screws tightlgkkbp.y:ktfk1; ;.m )zj :z98aqzhg ky 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 standard) 5hvqo.ayxf0 sw+7ap, adopted in the 18$^{th}$ century, was a platinum bar with two very fine marks separated by what was defined to be exactly 1 m. If this standard bar was to be accurate to within $\pm1.0 \mu m$ how carefully would the trustees have needed to control the temperature? The coefficient of linear expansion for platinum is $ 9\times10^{ -6}C/^{-1}$. $\pm$ =    C$^{\circ} $

  A scuba tank, when fully charged, has a pressure of 195 atm at 2tocw: 7b4i9a9)ix2brq3 lz0w j ku)ge0$^{\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 tgyi*tvb:f o czj6 v+xcn 5mb a9m1/g-:he 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 gro g6;o;)2yf;,7sskg v2zcg i vxsc yu7avity by tennis balls thrown vertically upward at it. How many tennis balls per s7)fyc 2 v;ky;osi2gvz7;oss,cx6 gg uecond must rebound from the lid elastically, assuming they have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter (spherical) bubble of air mvf5b 3n2l9xcb(yj *uk*ry 4 gfrom a depth of 14.0 m in a lake. Assume the temperature is constlm(ubf 5j92k*yr 4 *ncbgvy3x ant at 298 K, and the air behaves as a perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total qb2 hzii6jw q)0m8az)water vapor pressure in the air on the following two days: w)6) qzi2h qibm8z0 ja
(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 ofi8y9eqj7g)ffbo:k 0r)sg7hv iron at STP, and when it is a solid deep in the Earthk9f gioey)fg8:h7 sj)rb v7q0 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 gas at constant pressure, y za:*0+xnipns30 vuu the coefficient of volumen+sxzuu y i*0n pa0v3: expansion is equal to $\beta$ = 1/T where T is the temperature in kelvins. Compare to Table 13–1 for gases at T = 293K (b) Show that the bulk modulus (Section 9–5) for an ideal gas held at constant temperature is B = P where P is the pressure.

  In humid climates, people constantly dehumidify their cellars to prevent ror b0ku ,s o4v(i*rj.*cz;xdo pt and mildew. If the cellar io**,rj4 xpv.;zu orcks0ibd (n 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