Which has more atoms: 1 kg of iron osbz71q +-f jvz0/qun 05 ahlysr 1 kg of aluminum? See the periodic table or Appendia1b u07jzn ssf 5hlq0z/-vy+q x B.

Name several properties of materials that could be exploited to make a ther07t cq ;n.gudimometer..ud q;gnit 0c7

Which is larger, 1 C ie n)b3b;k qrv+qn.mb5ghk0 -6 /mirt $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with krpahp jw e2ux : zs5k63op:7zm2j63hsystem B, but B is not in thermal equilibrium with system wh jr2zsz pjoe:k2kh763 pm u :36a5xpC, what can you say about the temperatures of A, B, and C?

A flat bimetallic strip con9id vxkh -31fgus.-z+exnm6m sists of aluminum riveted to a strip of iron. When heated, the strip will bend. Wi-k+xgvdze fsn-1.xm 36 9hmuhich 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 linearas0fco/ w pfi7:, b1zw 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 diagramfp, 5r )csgkg. 4a2xdw 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 merc24r xkw, g )c5agpfds.ury 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 are fixed at the ends often cmncor ):.- iwu0c vxw( 2gj6ehave a section in the shape of a U. ) owx6rgv-cm0 u.en2icw:(c jWhy?

A flat, uniform cylinder of lead floats in mercury at/ a6+ xswemt;y 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometer is first placed in a hot tubvdib1 qa5zffy ly))p,ert: 4 d0 w:by(pqwa3( of water, the mercw:5yfl,4eb3 zv: y taqpywid1(a pd()r 0b fq)ury initially descends a bit and then rises. Explain.

A glass container may break iq .hzyd.laws 1ruvp d1-x6 h,8f one part of it is heated or cooled more rapidly than adjacentq6hs,. h8lpva.d1 1-x wrzyud parts. Explain.

The principal virtue of Pyrex glass isl6o jx c7+v-u)u :ctcd 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 resistanc j l:c uovt-c6)xcdu+7e of Pyrex.

Will a grandfather clock, accurate * ot+ijd t y.+ica;oo;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 causejfv1)mdnth: 4 its bottom and top to bulge so badly the can will not stand up. What has htf:hn41 d m)vjappened?

When a gas is rapidly compressed (say, by p h.muovc3q:)mn fo n*1;av:y tushing down a piston), its temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperature using the kinetic theory, in particular noting what happensoytvha 13n).m;:ufn vm*: oqc to the momentum of molecules when they strike the moving piston.

Will the buoyant force on an aluminum sphere submerged in watehtj;a ;t de;,kr increase or decrease if the temperatukda t,;et;jh; re is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows z6ir sx)1tq+q from kinetic theory and the relation between average kinetr+ s itqz)6q1xic energy and the absolute temperature.

Explain in words how Gay-Lussac’s law follows fd a: 1 7el(nf2mnm:ezrrom kinetic theory.

As you go higher in the Earth’s atmospher 5vxin8zd. as3e, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed an object to,no0hj7ol) bijj hft.)z 76 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 due to the Moon’s smaller mass. Ex7jn z 760f)o.tj)ib,jhlo htoplain why the Moon has practically no atmosphere.

Alcohol evaporates morq;;(bb+sac6,6sag 1 3b a 3jgrs jkhbre quickly than water at room temperature. What can you infers a+rjbc3rb,gbja1a3;q; ks6(b hg 6s about the molecular properties of one relative to the other?

Explain why a hot humid day is far more uncomfortable t5edne;:(j xh lhan a hot dry day at the same tempera(ehe5nxjd: ;lture.

Is it possible to boil water at : x(yp v qsh+:fbfhl.0room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when tc4 qzgk;1h6x px3g4 8bwg-fj4d2u pzwuhl 4p/he air temperature is the same but the humidity is different. Which is more dense, the dry air or the humid air at the sam4hwu ppxz6/- udcbl434h w pz4j2xqg81gfg;k e T? Explain.

Explain why it is dangerouetr2,htf* ww 8jzla1bi eh)67s to open the radiator cap of an overheated automobile engineb7ih wtaezj2) 1r, el8*6tfwh.

Why does exhaled air appear as a little wdg1rd 4jgfkna 2j k.8*hite cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram gkh*7;y65nszi y*jodlb mv- ,copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold rin9 kkqt cz1h3,ig compare to the number in a silver ring o9t3 ci,qkzk1hf the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°Ff c3iz*smn4gr j-7tna k*y6l1krva *(. What is this on the Celsius scale? tva* 7l jkmn6y1a*izrgsc3(frkn4- *   $^{\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 bk i:ha 2c9 5.dlmow,nr/7ozr 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,sp6e jbpi mio bk+cc *.69i 9xa.dh8:q the alcohol column has length 11.82 cm at 0.0 qbikdo ic.xs6mphai 6:+ c9b 8p.9 ej*$^{\circ} $ C and length 22.85 cm at 100.0 $^{\circ} $ C. What is the temperature if the column has length
(a) 16.70 cm,    $^{\circ} $ C
(b) 20.50 cm?    $^{\circ} $ C

  A concrete highway is built of slabs 12 m long (20 bn /j 1r j2ew s2.o47fn1elljy$^{\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 approxim/8w f5 egib/pmately 300 m tall. Estimate how much its hei5mbie fg/8/ pwght changes between July (average temperature of 25°C) and January (average temperature of 2 $^{\circ} $ C). Ignore the angles of the iron beams, and treat the tower as a vertical beam.    m

  To make a secure fit, rivets that are .hw21s z ofl9hlarger than the rivet hole are often used and the riv l.w1sho 9h2zfet is cooled (usually in dry ice) before it is placed in the hole. A steel rivet 1.871 cm in diameter is to be placed in a hole 1.869 cm in diameter 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 /w:k;a+oe ef(hje 8rn 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. Whatp *peay:5 oa-lp 5j(2snhuzo5 will be its change in volume if it is heated fryu ej*hp 5:a55aozs p(-2n polom 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350* yv9oxx+*s cns3ny9j.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 o/r 1+ p mah-i zo4gb3dpz2ha3gf 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 irore aq0f/ah4++ ncsk /yn. 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 1/q:gqms i:/ ,bb ynazze*rd28 jvdc5it can expand in essentially one direction only, show that the effective coefficient of linear expansion is approximately equal to the coefficient ofj/z dqmnc1i:vze5s g *b 82br:, a/ydq volume expansion $\beta$.

(a) Show that the change cx s.najo ds; )/*4srcin the density $\rho$ of a substance, when the temperature changes by $\Delta$T is given by $\rho$ = -$\beta$$\rho$$\Delta$T
(b) What is the fractional change in density of a lead sphere whose temperature decreases from 25 $^{\circ} $ C to -40 $^{\circ} $ C？

A uniform rectangular plate of length l and width w has coefficient of6vd8gg cx 7nbcye3/1c linear expaced73/cnyg1 8 6xvb cgnsion $\alpha$ 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 sopqre /)yqjp8+lid, $\beta$ = 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 clockqhs 51dl b:y3y is made of brass and keeps perfect time at 17 :3qly1sh5b yd$^{\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 thermometer has an inside diameter of 0.1s ud7 b3,jx(0i8afygu40 mm. The bulb has a volume o0,ixgb(udsy f3a78 ujf 0.255 $cm^3$ How far will the thread of mercury move when the temperature changes from 11.5 $^{\circ} $ C to 33.0 $^{\circ} $ C? Take into account expansion of the Pyrex glass.    cm(b) Determine a formula for the length of the mercury column in terms of relevant variables. Ignore tube volume compared to bulb volume.

  A 23.4-kg solid aluminum cylindrical wheel of radius 0.41 m is rotating about 0nak.txl c-2yits axle on fr0- cnxl.yakt 2ictionless 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 1951ep: qy tukgikt, 7h5°C. How much stress is required to keep it at this length if the temperature k5ty,eg 7u9: ptqk1ih increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cro01i ,, 5d48t ov6bcbd e4k bkml1xvnmfss-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 1d- zrvjg*p a emmwy:h n8rk9 y/-+rf/234.122 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 the Kelvin+*gjhfz2w0xw b1whv9 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 Fg: npdun qj:/miclh/6w y)tz 8n .e(-4nda g:rahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Eartr xyqw: atf;t6uo45h+ h 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 press 4 a4;r(pwodhrure and a temperature of a4 wr4hrdp; o(about 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 o)jqywx;vws8tr v qe5x*)5t:hxygen at STP using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of nitrogem2cn*zg(a :4 ;qaqcxq+ w:xf in ($N_2$) at an absolute pressure of 3.65 atm. What will the pressure be if the nitrogen is replaced by an equal mass of $CO_2$    atm

  A storage tank at STP contains 18.5 kg of nitrogenu0nf0z7 tu 3tl2vh(n/;w knn c ($N_2$)
(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. 4wxfj wm7fe*n /0w6mc0$^{\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 containevrg u6 ;oultj6,y.p i(r holding 105.0 kg of argon gas at 36 g ,o(lp .ujrv6uy;it85 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 * rm5 o0pgtmxo/tf,uhke(httt(3 3(lkg of $O_2$ gas at a gauge pressure of 8.70 atm. If the oxygen is replaced by helium, how many kilograms of the latter will be needed to produce a gauge pressure of 7.00 atm?    kg He

  A hot-air balloon ach)kw7v39 wkcq fulh4nj1p -c 8yieves its buoyant lift by heating the air inside the balloon, which makes it less dense than the air outside. Supv8jnkycqp hl 7w13u9 f- )ck4wpose 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 wit1-i5 6revw jheh 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 18.0 5j8yvo8z+d hq$^{\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 esca hvnr(fl3u1d0f 2 mjs9pes 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 molec21hswu ;nl v 8/caxn.sules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How many mo e2g i*;qgwv;plecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of- rrsyoh u*5n; (a) moles,    $ \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 58-l epcj)ks8k m(s z2y+j -mrgifo*x:.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 2.0-L breath wgkz ldz,bz* y :lva 8l4zx)-z wwy4,4you inhale that were also in the last breath Gall w zwk:,44zz,*8lz yzxdw-yaglb )v4ileo took. [Hint: Assume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of an oxygen moleculej(jwa ra3n5qb j8c35t at STP?3 n(awca53j8rtjq 5 jb    $ \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 z **es8w*a0 5h s8etxyfeyq+ia temperature of a zf0eya* 88h5is*w+y teqsex* bout 6000 K.    m/s

  By what factor will the g oz0 *jj0:c,1r kzjeurms speed of gas molecules increase if the temperature is increased froejj: gru1c* 0z zkjo0,m 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, p;ylvooh2:kk () 5ag vgiven in units of km/s: 6, 2, 4, 6, 0, 4, kvg)hooa25kl;p v y:(1, 8, 5, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at 20.0y dao )q*iqav6u3 ck-ecs,7*w $^{\circ} $ C is to be increased by 1.0%. To what temperature must it be raised?    $^{\circ} $ C

  If the pressure of a gas is doubled while its volumeop(+ixv a,4e l is held constant, by what fa iv 4pe(+xalo,ctor does $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is6.iyn ,gdvq *i 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 qsu j99oxzsrijix ,8 8m4 cj38of two gases at the same temperature, the ratio of their rms speeds is equal to the inverse ratio of the squx x8r8i,q jcziuo 9s9jsj 8m34are roots of their molecular masses.

  What is the rms speed of nitrogen molecules co(u,( 3g gyclbm2 x:gvontained 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 mol sva r,k/dpg nqocu*h )gmm51tz4 , e90/oitr-ecule 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 mo47( 4t+ivmsescp dq s8lecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed od,l, 5i b,t 96hhzxzljf an amino acid whose molecular mass is 89 u in a living cell b,h, ,l9zthxd6i5zj l 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 written P )psm/m wtwpaoagj1vx j/,)92 = $\frac(1)(3)\rho v^2$ where $\rho$ is the density of the gas and v is the rms speed of the molecules.

  The two isotopes of ur8xw)abz vj, wiyv :pvj/kz 02yvn,8/sanium, $^{235}$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,8f*e afb+ str /sgu i7)lo2/hn in 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 isfeb1d a+t:f 4j 0.01 atm and the temperature is (a) 90a1e+4tj:db f f $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity is 50% on a day when th.ba d1c 2ct)sle temperature i)2 a.tl s1bdccs 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place whez 5.jex3 ji:)feh a3icre water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the moun0;) nthtz htv.tains is 0.72 atm, estimate the temperature at which water boilsz vnt th;t.0)h. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of water is 5m8rua om1;g*a 30 Pa ana1ar8* muo;m gd the relative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on ap l7-e udg4jm. day when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cooker if the water is boils5,8z0z yvib oing at a temper szy,z oi0bv58ature of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room of volumiu yz(i( 2;4bpo hi8iee 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 dewx+ anc7 :6*.f.nfbnn zz6qhh m 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 for3 51boobdp*6 30f xhzg8x unsa a glycine molecule (see Table 13–4) to diffuse a distance ofo5s u0p3 zhxogb 8dxa *1n63bf 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 tinyz(r zzdr4j)l jn)wetnn-9;n, tubes called tracheae. An average trachea is about 2 mm long and has crlrjn ;)w,z9z) nnz4tj-er d( noss-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 hapa i,ey8nvc.jro3y7 ( s been calibrated at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A precise steel tape measure has been calibrated at 20dm;c -j t fvm(+q mf4k0wlotod8; r73b$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A Pyrex measuring cup was calibrated at normal room temperature.pirsos;;v18ro zpy b7,i +xf4 How much error will be made in a recipe calling for i;sopyz78; r fo4rs1bxp+iv ,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 init flh4vi yy,:0fk: ekf6ially 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of the original gas remains in the cylindf y,4:eyvlik:k0 fh6f er?   

  Estimate the number of air molecules in a room of length 6.5 m,cfq,-v feqr-*q2 -fqn width 3.1 m, and hqq* 2f ,qq-vf --ncfereight 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 magl)-w4r+poo ficvo7 * ;s 8opftter 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 best3;0a.x;998t yjtafi eh3 zvh7n9h dj oaf)enm available vacuum techniques is aboutxj9jhinn m .aa33f; yeh7v8)eo 0z9f ttha9d; $10^{-12} N/m^2$ 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 bepc/k0)rsf wa9 -gp 2jylow the surface, to what volume would his lungs expand if he quicrcfp- )g/p wyj02k9askly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmosphere at a speed a b3rxlo3 a :bwv6k9z0g)ctr.of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this speed correspond to what temperature? (Because of thi x tr3 oglac)kazb.0b: v9w36rs 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. 3x br4p ob5:oy5q itleww45d 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 volumemxvpq k fcbdc m.31v fe9)6,k) of 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 i .8tqgupw-+i(pa lx xw,j 1v3of atmospheric pressure at the surface of the Earth, estimate the total number of air molecules in the Ear w-3.pp wx iq(gl+av1 tux,ji8th’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen ,-r:(y gg pz- whjfoka2y4-whmolecules contained in a 7.6$-m^3$ volume at 4.2 atm if the total amount of nitrogen is 1800 mol?    m/s

  A standard cylinder of oxygen used in a hospital has gauge pressure = ;+ 2ki /t0ovf;xnbe ui2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure, fnbuvxie /;;k+0oti2 is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl ofa* ah3j3te2mkxe 9 * lvlbm4g4 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 0iiha fw om9k-i 0en.r pg7 bsc0vz):/8$^{\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 equator a k24f81 nuz xzq5c7aukt 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 at edt b+:bw3 wq3/ (mqqy20$^{\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 fbx/ 4q.l yn/vthe 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 atyb(no(19mowot 4 dlp3 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 Eart3ih a;ntws(e3 h 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 li-;xwc.a 6qezrc: thjvj+5 6se d is suspended against gravity by tennis balls thrown vertically upward at it. How many tennis balls per second must rebound from+jtvh. e 6c6wr:xej-qz; sca 5 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 (sph,rv jyubtppea a1w.acr; l1 r8, 3p*g-erical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the ae1g,ylp*bru,r.1j caar- p3v;tpw8air behaves as a perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure in the air on the following two du3r .i( vnjwl0ays: . l3 0vrwj(uin
(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 tg zw h5(lu,rd6yhw.j:he density of iron at STP, and when it is a solid deep in l.5wdhrju gh6, (z w:ythe 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 sho( - )jmcsgqw6sw that, for an ideal gas at constant pressure, the coefficienms)jg-s( 6cq wt of volume expansion is equal to $\beta$ = 1/T where T is the temperature in kelvins. Compare to Table 13–1 for gases at T = 293K (b) Show that the bulk modulus (Section 9–5) for an ideal gas held at constant temperature is B = P where P is the pressure.

  In humid climates, people constantly dehu6w u5(s:v1dqda/mwt.vui4y p/e4 iu tmidify their cellars to prevent rot and mildew. If the cellar in a t/y:( ua e v/tm4wuu4ii. d 56s1vpdqwhouse (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