Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodic table o0t*8horm, :+t3 ipa is0 cfgwsr Appendix B.as m:8c+fwgpt * ts0 ,iri03ho

Name several properties of materiawbqmi 7/vj1a7ls that could be exploited to make a thermometerb1vq7j7im/aw .

Which is larger, 1 Cd ,jy-7eqhu- i $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with systee6qiim0e;ya9 m B, but B is not in thermal equilibrium with system C, what can you say about the temperatures of A, B, any6ee0;m i9aiq d C?

A flat bimetallic strip consists of aluminum riveted to a strip hd gj, z//jn;s.1do b3b l6ospof iron. When heated, the strip will bend. Which metal will be on the outside of the c;6 n3jpb,gls1bzs//h. dodo j urve? [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 linearq m/y7mlrlv8 : 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 diagreeyq.br7l ir on:0p b k1ws.15mb.u y;am 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 flow to touch both contact.b .:e5kr1b1iyq7sro yw n;m ube0.pl 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 :qudo bv8n em24h8du8 ends often have a section in the shape of a4: 28uo dmhe8n8bqdvu U. Why?

A flat, uniform cylinder of lead floats g*qk :h7rn1ma in mercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-vhf:07 b8yhimin-glass thermometer is first placed in a hot tub of water, the mercury initihmv8b 0f h7y:ially descends a bit and then rises. Explain.

A glass container may break if one part of it is heated or c8f+ ru 5) pgu,bkrs5)ic3yt iqv2tv 9booled more rapidly than adjace g9, r3uify5vu pt)bvtc8r) +2qkbis 5nt parts. Explain.

The principal virtue of Pyrex glass is that its cojlxdeol*zb 0e nf 7d 5,z;rn w1l w;x0t.+:tzyefficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this f0dtlnlozz ne7zb;wwt,*+j.xy rd 0 :x1e5l ;gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurate abvipk.s6k 2ut 5 ;l0gmt 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 1dyl+r6 gk yqlb,a:9wto bulge so badly the can will nok 1+dl9ar:, ylq6wybgt stand up. What has happened?

When a gas is rapidly compressed (say, by pushin ;viw2poz /g4jok0rv2g down a piston), its temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperature using the kpi vzrgj ;0w2k/oo2v4inetic 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 so 2kivw4mdo: 1 a.qsj.ubmerged in water increase or decrease if the tempeq : v.odksw a24mo1j.irature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Cha lyqt+4x0 7wju ugcc/:rles’s law follows from kinetic theory and the relation between average kinetic energy and theu 7jgxy/+q:0lcu4c tw absolute temperature.

Explain in words how Gay-Lussac’s 3 3(9k fts.vt ttru-3mjv (ocmlaw follows from kinetic theory.

As you go higher in thpcy; 0 ujd6/ p w f*yp8rqt8o,sm:q0dx.hb 8lme Earth’s atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for t5 h(caod v7*z4o- c7wo ik6vjthe Earth refers to the minimum speed an object must have to leave the Earth and never return. The escape velocity for the Moon is about one-fifth what it is for the Earth-joc (a c oi747wodt5v6h*zkv due to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at room temperature. What can ;gehv* m9,vtsyou infer about the molecular properties of one relam,v sg;t* veh9tive to the other?

Explain why a hot humid day is far more uncomforxzp */u7 b(cemtable than a hot dry day at the same te(zxcm/bp u7*e mperature.

Is it possible to boil water at room tn.rbcony/cms.2 m ,qu.,e t7 eemperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when th*-m9pzus+ jk te air temperature is the same but the humidity is different. Which is more dense, the dry air or the humid air at the ss 9ztj-p+ *kumame T? Explain.

Explain why it is dangerous to open the radiator cap of an overheated s0w-e6 xn iu5bautomobile engine.w 6-exbui s50n

Why does exhaled air appear as a little white cloud in the n)z; d-yk n1oke(/vntwinter (Fig. 13–28)?

  How many atoms are there in a 3.4-gramr6ieb., gq cr* copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare to tgp,oi*d,;zzlc* yes6he number in a si is6,z*dle;g *yzo ,cplver ring of the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this on the Celsiusez9xu93vomk wren).4 scale?3.e kmu9zve4r9 )wonx    $^{\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 and0k klvu2tht833cor- mhi 6pn9 lowest temperatures recorded are 136 $^{\circ} $F in the Libyan desert and -129 $^{\circ} $F in Antarctica. What are these temperatures on the Celsius scale?high =    $^{\circ} $ C
low =    $^{\circ} $ C

  (a) 15 $^{\circ} $ below zero on the Celsius scale is what Fahrenheit temperature?    $^{\circ} $ F
(b) 15 $^{\circ} $ below zero on the Fahrenheit scale is what Celsius temperature?   $^{\circ} $ C

  In an alcohol-in-glass thermometer, the alcohol column has length 11.82 1bg gwjn;ibz7br hy(7d+:(tdx)x bz )cm at 0.+; :hntrb))i1 7(gybjzd7wxbd gzb (x0 $^{\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 slabsudl*u4 kzu1v t2ce 1,n 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 approximately 300 mzogt o y/c k;o)/h98:n ig(fma tall. Estimate how much its height changes between July (average temperah8) ogki:/gnmtoa(cz o9y ;f /ture 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,iz.2enqitx2a)ve9- 1 p fnfjxi 8na(3 rivets 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. Axaziq(3jve2 ie tpi9 a)-81n xffn n2. 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 al4sq zf6 6h46 kgkkjq0t 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 diaqt z ,+ +ondiz+5j8jus)yh3;sfola+xmeter. What will be its change in volume if it is ht ;is,j f5u)++n ja38zdyxs lz+oqoh+eated from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 3hqf*n 34y.l5 n .brcnk50.0 mL of water at 100.0$^{\circ} $ C. If the temperature decreased to 20.0 $^{\circ} $ C, how much water could be added to the glass?    mL

  It is observed that 55.50 mL of wat vhkmm/k, e30xt-s v;jer 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 irom/:w l1d1ghkcwt0 :lm j7;afpn. 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 c zi 5kke3 hy;ul0rrg,5an expand in essentially one direction only, show that the e 0k;zr uhig5k3l, er5yffective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the)m( caf w;e5br density $\rho$ of a substance, when the temperature changes by $\Delta$T is given by $\rho$ = -$\beta$$\rho$$\Delta$T
(b) What is the fractional change in density of a lead sphere whose temperature decreases from 25 $^{\circ} $ C to -40 $^{\circ} $ C？

A uniform rectangular 93d89ekmm /g4qt:z u4t ir(rvxdroi* plate of length l and width w has coefficient of linear exi* tdo z(/uix44 d93r:98rerm mgtvk qpansion $\alpha$ 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 isotrop1dm(bf7san c*ym + l8nwo im57ic 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 perfemxz e1 hn6,j:zct time at 17 mxn6: zhz1e,j$^{\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 thermometerf(a4f;eu/;m s ku;fxs *xvw*h has an inside diameter of 0.140 mm. The bulb has a volume of 0.(4suh ;;/m xxkuefv* fafw*; s255 $cm^3$ How far will the thread of mercury move when the temperature changes from 11.5 $^{\circ} $ C to 33.0 $^{\circ} $ C? Take into account expansion of the Pyrex glass.    cm(b) Determine a formula for the length of the mercury column in terms of relevant variables. Ignore tube volume compared to bulb volume.

  A 23.4-kg solid aluminum cylindrical wheel of radius 0.41 m is rotatinaj o)tzn0h;:peaa 34r g about its aah n:0)4 zjapa3tore;xle 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 req:c1n-w m)i1p*phq.lh d f7oneuired to keep it at th -nlq.phh)1efpi*1 :wmod7c nis length if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of ce85hx nh3e 6anross-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 134.122 cmzscp;whzj(b+2 7: tei 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 thecdd8i38g0 9hv xwafg: 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 Fahren n pk;kwozv,,-heit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun arei, swyc p+po ;md.mnwyw)92a- 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 atmo eq som7pv8;ksa(vz,6spheric pressure and a temperature of aboue,av (8 kop;7msv6zq st 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 ocwc-uocwu, )6xygen at STP using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6u7 wb,sems p(3 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 STrq366ypxit u*P 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 is+cv mqn8 hi (ic3d//+lw a;c2i3cpdp x 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 insideo w7papet(l4s/c .g7n a 35.0-L container holding 105.0 kg of argon gas at ol g/. t(e7n74psw cpa385 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg of tdxf* uh)g)5v $O_2$ gas at a gauge pressure of 8.70 atm. If the oxygen is replaced by helium, how many kilograms of the latter will be needed to produce a gauge pressure of 7.00 atm?    kg He

  A hot-air balloon achieves its buoyant lift by heating the air inside9(4blh og+1j3lrstrab,*tj h the balloon, which makes it less dense than the air outside. Suppose the volume of a ballrt(sg bo +91ljl3 ahhb*rtj4,oon 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 4bz qt)ptq psf5+2f)o6 e; ld z2( e-cfod1jxuair 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 18.0 dyadpm:zyewhf f;o * 4e 2c7z58wk3/t $^{\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 balloi+ 1pp fpnsyv :jf2,hsrhq .1.on 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 molsbvwo plnv5t+4t5 ttcj412:4 8an2 kxq.gocqecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of watefpyp5j.; hslh;-5e ab3 ejf6s r are there in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) )yy2d f fdx;dew:/,m mmoles,    $ \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 volumex uh+..0yq v(g9d yupe 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 air are in each 26)4f z a*pvfte.0-L breath you inhale that were also in the last breath Galileo took. [Hint: Assume the atmosphere is about 10 km hit)fv z fa6pe4*gh and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic 0oj p:/mri0 yhdv kkfbd:7w 89energy of an oxygen molecule at STPdmo:v/p r9kijfw : y8bk7hd00?    $ \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 0k s ommhe *9etoj(ea .;df1fp -fb.+fsurface of the Sun at a temperature of about 600*h +sjemk9f a0oebote;. pmdf1-(ff.0 K.    m/s

  By what factor will the rms speed of gas mc/2 c+m ao l:plsttf*-olecules increase if the temperature is inc-ctsptal:c* mfo2 + l/reased from 0 $^{\circ} $ C to 100 $^{\circ} $ C?   

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

  Twelve molecules have the following speeds, given in units of kb jjj,.p /tf4nm/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calculjjpb /f4n. j,tate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules icw3gp )x5q0ga , 2nfn3k bmjb*n 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 gas is doublel4idr g9a*re.d while its volume is held constant, by what factor doi4 .a*lrd9 rgees $v_{rms}$ change?   

Show that the rms speed of molecxev(.d 1jzzk+r /j5i bules 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, the ratio of t, r,/ yn-hnv5k lken.dttd0v8 heir rms speeds is equal to the inverse ratio of the square roots of their molecular m0,.d5/ yt dv h8-k nknvrnl,teasses.

  What is the rms speed of nitrogen molecules contained in a2u dt- -d8kmu hx2j,fbn 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 molecule k)-m.s.c w krfat 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 nitrogn6t) al70ac62ave: tpkdcoj4en molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecul vjha92 7wtsb0ar mass is 89 u in a living wa s097vtj2hbcell 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 wg* 0kaj uxx;w8ritten 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 uraniumss: 8 ri/ 2foe-/owohb, $^{235}$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 phase qhri35tgfoqhnzia c :l- 1r8l84y :-ts 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 temperature is (agyv0uzd(m)qblw)9;( 8vq p0ts8 tvte) 90 y;mtgs q8q(0vv )0e bdutvpzlw 9t8() $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the9, 5 jxvefz 8smzoj,:n humidity is 50% on a day when the temperature ozs, jfzj, 9vex :8mn5is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water boils at+a+.nj/**;v1y rbdfowtv osz 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a par*avzu4x( ex.d ticular place in the mountains is 0.72 atm, estimate dz .xuex*(a4vthe temperature at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the pao. ri5mq r+oe)rtial pressure of water is 530 Pa and the relatmor5qi )oe+r.ive humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the ten. t*bl ssm3,bmperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cooker if the water is b3;bvb jz2y5cj 1hetuzm : 3+proiling at a temperature of 12+ cthzp:v25zr 3 ye b13jmu;jb0 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room of volum84vbfod , 4ua7eg adp;e 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 point of*mj8ukq4 jyn3 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 Tablson+sf5yld :z + 15jxze 13–4) to diffuse a distance ox+y +5 zn: jz15dflossf 15 $\mu m$ in water at 20$^{\circ} $ C if its concentration varies over that distance from 1 mol/$m^3$ to 0.4 mol/$m^3$ Compare this “speed” to its rms (thermal) speed. The molecular mass of glycine is about 75 u. t $\approx$    s ([color=rgba(0, 0, 0, 0.85)]Round to one decimal places) $v_{diffuse}$    $ \times10^{ -5}$ m/s
$v_{rms}$    m/s

  Oxygen diffuses from the surface of insects to the interior through tiny tubeso v9a+y(nl km4m qjt+e) dy0(h called tracheae. An average trachea is about 2 m0+y 9jm+atohvn yle 4(dm)kq(m 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 2d2lei7p9 a/vnyh subo3i6 2*n0$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A precise steel tape m rrv c2kno; nf54c8;im ipp)z+easure 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 cal7 ;ckhoftz ,r d8i6/pnibrated at normal room temperature. How much error will be made in a recipe calling for 300 mL of cool water, if the wh8r7;k /tn ,fido6zcpater 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 inittaby k90fa6a9myr/ bfing*61 f q* ht tj7::wgially 28 atm. After many balloons have bthm t*/9 *bnab7k:wrq6 a ya:fgj0ff1gt9iy6een 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 in a room of length 6.5 p(/he (/zft5v+daz a.cycu y 0m, width 3.1 m, and height 2.5 m. Assume th cfdv(ay5zu.a/cez0htp +(/y e temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of mk5u3 +eg,zvud atter 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 best available vacuum techniques u z5m 9ozc8 qrxk(0u2upzfjvp6y1y5.is about2rf1p(8qcp5 v zouyxu.m5k9zj6 0yuz $10^{-12} N/m^2$ 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 olv6//oxf xiq brf4c*yy)4o 4wf 5.5 L when 10 m below the surface, to what volume would his lungs expand if he quickly rose to the surface? Is this advf4 /c r4/l)6y4xyoovbf*xqi wisable?    L

  A space vehicle returning from the Moon enters Earth’s atmosphere+0 r:qw4epv q:wu30zhdw iu4i at a speed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle uqwu4h0 i 0rw i: wz+ve:pdq43with 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 4 qe +qcq,ug6n 2k1mr 6qssjy/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 of5cl5qywoq r2cl ec7zxi8f6 *ex8si,; 770m$^2$ (a) What is the total mass of air inside the house at 20$^{\circ} $C?    kg
(b) If the temperature drops to -10$^{\circ} $C what mass of air enters or leaves the house?    kg

  From the known value of avhpih4 nf82yku,-1 g7* 2rokomupe, ptmospheric pressure at the surface of the Earth, estimate the fi 2o8u epp,h2-mk1n v*ukh yp4,7ro gtotal number of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules cont pd92qwwsn(q5ained in a 7.6$-m^3$ volume at 4.2 atm if the total amount of nitrogen is 1800 mol?    m/s

  A standard cylinder of oxygen used in a hospital has gauge pressure = 20 hf)bxnm 0wf4800 psi (13,800 kPa) and at T = 259K How long wi)8bfn4h mxf 0wll the cylinder last if the flow rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats 7e-aoyn n .:.rn/m ltuin 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 yxw yg55wl54qi8 ox l/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’sta).r o ml w8o oze++c/3unh8o equator at 25$^{\circ} $C, but then was heated to 45$^{\circ} $C, how high above the Earth would the band be (assume equal everywhere)?    m

  A brass lid screws tightly onto a glass jarr1x4a n ,s bos+w.dwg/ 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 stand;-s (.u* xo4wr);b: hdmyja*l bfi rpeard, 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 l n+u/om3yks k z2f9a;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 the4o+opm4 ml tzid)3hbxgd .30 m 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 suspen(j ok y 5q8l8/gsr(ffnded against gravity by tennis balls thrown vertically upward at it.rkl8(f 8j/fn5ogy s(q 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.oz5n +),uwp xe00-cm-diameter (spherical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the air behaves as a perfect gas. How large is thou,nw +) exz5pe bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure in the air on the following two days: f1g (vg n6zqmvzc/xf1w q+04i,)v iup 0iqxi 6 vg1vff1cwmu+n (4zpg) /vz,q
(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 differjp et(7;o.jz nence in the density of iron at STP, and when it is a solid deep in the Earth where the ttjeo j7;(zp .nemperature 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,pvz,*zb 6ij4o0 kb;xp the coefficient of vbj o p0*kixzb4zp 6;,volume expansion is equal to $\beta$ = 1/T where T is the temperature in kelvins. Compare to Table 13–1 for gases at T = 293K (b) Show that the bulk modulus (Section 9–5) for an ideal gas held at constant temperature is B = P where P is the pressure.

  In humid climates, people constantly dehumidie3,yi+nl 0vul fy their cellars to prevent rot and mildew. If the cellar in a house (kl,i +l 30yevnuept 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