Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodic tl gcwu 7*(hki-able or Appendixc*lk -( ihg7uw B.

Name several properties of materials that cou8)woz s;5uhz+ 1eyhik, p bf5nld be exploited to make a thermometerieh h, 5w8k5zpb1 +u)y;nfsoz.

Which is larger, 1 C g.vz l1 yqtj a+n37rv7bi /a)m$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrisdmebb. m+0(-d rg )hkum with system B, but B is not in thermal equiliem.)(+ bm 0dsbk-rd hgbrium with system C, what can you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to a strip of ir 6o.wal18yuvcdlq430kshvo. on. When heated, the strip will bend. Which metal will be on thao ycvqkdo8lu.6.w 3vh 4s1 l0e 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 coef 8d cgp4o)uai)ficient of linear 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 diagram of a simple h+uk oh)8r jo cz;zy p;ec if07/ht0-nthermostat used to control a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch is a glass vessel containing liquid mercury that conducts electricity when it can flow to touch both contact wires. Explain how this device controls the furnace and how it can be set at different temperatureoc0tkzz h87ypen+ r;hfj)cu h 0 /o;-is.

Long steam pipes that are fixed at the ends often have a section inzmd8q7+ ni9+ ft5hqui the shape ofnzi5 qqu 87+td9m+f ih a U. Why?

A flat, uniform cylinder of lead floats in merc 1fio:gr /9lm7pzx 8ncrhhur(/)q)r xury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometer is first(q 4nyoxvc :9rzf:1vc placed in a hot tub of water, the mercury initially descends a bit and then rises. Ercfn (xv:zo q91v4y:c xplain.

A glass container may break lla5b)jqv ,yc:qq 345x /iaikif one part of it is heated or cooled more rapidly than adjbl kj:vaq5x 4qa5l/ qcy 3),iiacent parts. Explain.

The principal virtue of Pyrex glass is that itsaaqnbn0jc ssik u .n --n(-92p coefficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrex. npsn n bc-.9(0 uqisa-k na-2j

Will a grandfather clock, accurate at 20 p/zhjvcp :kn )*o/0ju$^{\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 bulgey87rm4m3 u;1gg,,u8rf pia bv a)qado so badly the can will not stand up. What has 7, ar)ao b81qgdv, riu 8my;mp3ga4fu happened?

When a gas is rapidly compressed (say, by pushing down a pix lm2 /jlpti3cd) ,:roston), its temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperature using the kinetic theory, in particular noting what happens to the momentum of molecules when they strike tojlmr/d3, l :xc tpi)2he moving piston.

Will the buoyant force ona6pctaoxw10 hcoxj,7 sdkgx:6w) q j01vh3 2k an aluminum sphere submerged in water increase or decrease if the temperature is increased fr1dxw v30khj6toqjag, 2poxacs0 x7:)kc hw16om 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Chartsxlov+p zf) e0p.v/2les’s law follows from kinetic theory and the relation between average kinetic energy and2p/ v.of+zslx0) tv pe the absolute temperature.

Explain in words how Gay-Lus1/lri;zpy oys7:kaai*nlh;esqc2 u,g 5) x; w sac’s law follows from kinetic theory.

As you go higher in the Earth’s atmosphere, the ratio ofxc. xa 9os;rrh k sr1v-wb*p*4 $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed an obje eil mtv:u(1 i)vj4c3rct 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. Explain why the Moon has practica(13cir uiv4 ):evjtml lly no atmosphere.

Alcohol evaporates more quickly than water at room temperature. What can,y *sby3do lle(9,1ts pdgd;n you infer about the moleculy e,,t;9*dly(3sl ond pdb1gs ar properties of one relative to the other?

Explain why a hot humid day is far more uncom:1 mtdt660h03cft3hv 8xru+ gtvzrrz fortable than a hot dry day at the same temperattdh+ 1 0:0 htgzrtumvx zr3668tc fv3rure.

Is it possible to boil water at room tempera ih0cloldu 8;1bm)5ev tm 6*hhture (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the aik mhh,pjo6w6 p*e(o)o-ff 2w tr temperature is the same but the humidity is different. Which is more dense, the dry air or the humid air h- 6m6( fotwwfk),2h o *jeppoat the same T? Explain.

Explain why it is dangerous to open the radiator cap of a5w8ykuc8otgqn ;o - 3kn overheated automobile eng knuoo5gt8yc8 wk q3-;ine.

Why does exhaled air appear as a little whi1 mt*gmc.m c;+d 5bopqte cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram copper penny?8vksv z)s8x:d    $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.53 lcn4fvy x3 w2c1c(fi-gram gold ring compare to the number in a silver ring of the same mn2wv4xf 1i(y lc33fc cass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is thqm f nzw8j79.8pga6ik tasz: )jl;o.his on the Celsius scale?9s. mpgjlji68f)nk zoh.wza8atq : 7 ;   $^{\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 low)a-2.j5gd le xwwxe2qest 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 alcoholudg12*+z j w 6r;irnxm cx(j):cde2f mh7y,jm column has length 11.82 cm at 0.0 j *d2njr 1 dgzyj+muie,x(crm)cx7w6mh :2 ;f $^{\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 bj2i3ncslcbzzu k-6 a;2 ,c/)zq 9kvfx uilt of slabs 12 m long (20 $^{\circ} $ C). How wide should the expansion cracks between the slabs be (at 20 $^{\circ} $ C) to prevent buckling if the range of temperature is -30 $^{\circ} $ C to +50 $^{\circ} $ C?    m

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

  The Eiffel Tower (Fig. 13–29) is built of wrought iron appro+cr8ub 54c lc 3rc;prbximately 300 m tall. Estimate how much its height changes between July (average u;l 3pr+bccb4 8rrcc5temperature 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 larger than the rivet - wrj8ooh 8bl)hole are often used and the rivet is cooled (usually in dry ice) before it is placed in the8ro lh-j)8bow 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 atu vqvo3mf1c 5cg9b,86.exgg w 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 ber-z.84ht/vvl 4xb c ub its change in volume if it is hea4 ub.bzvtlh/c8xr -v4 ted from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass isyszyciau0i/:+h s r7*kr* j2 l filled 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 mL of water at 296 mmtm1 bhdy6k tbg1h (o6cymaf2)o: 0 $^{\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 iron. At 20y. / tup(v*bmr-hm7s2xb jk3 p $^{\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, ny d/ nmovr qhxe;bk6u. b121a9arrow vessel so it can expand in essentially one direct2n1 /x1kvramyd6oeq;.uhbb 9ion only, show that the effective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in ther/x:m cd8 :h+ qcw.bw/wmfw6x 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 coeffd6lcix1 /w utpjfm,f (r*h,,w icient of linear exxm(u ifwd6w/c,phj1,,r lt f*pansion $\alpha$ 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 isotrotkyjy 6shx34p a s67s7jlf06ipic 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 is8mli3i 4 qqgu; made of brass and keeps perfect time at 17 quqg l4im8i;3$^{\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 insid+kwb--kua7-k fs tno3e diameter of 0.140 mm. The bulb has a v-ntsw- k3ka7 f+obku-olume of 0.255 $cm^3$ How far will the thread of mercury move when the temperature changes from 11.5 $^{\circ} $ C to 33.0 $^{\circ} $ C? Take into account expansion of the Pyrex glass.    cm(b) Determine a formula for the length of the mercury column in terms of relevant variables. Ignore tube volume compared to bulb volume.

  A 23.4-kg solid aluminum cylindrical wheel of radius 0.41 m is ; 7k7fnv9 m-mnhx0aqg2 9;mgjew4,fisfsx,wrotating about its axle on frictionless bearg 7qmamnf9v;,fjxi7;nemw- 0wfh9 24gx, k ssings 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 relasb 4u/mv6 df(1-pt+ dx/v jiquired to keep it at this length if the temperature increases to t6iv41-d( p+sxvbuald/m / fj35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cros oij .xyyw /nsc97z8x k)0kts)s-sectional area 0.041$m^2$ is rigidly connected to two vertical steel girders. If the beam was installed when the temperature was 30$^{\circ} $ C, what stress is developed in the beam when the temperature drops to -30 $^{\circ} $ C (b) Is the ultimate strength of the steel exceeded? (c) What stress is developed if the beam is concrete and has a cross-sectional area of 0.13$m^2$ Will it fracture?

  A barrel of diameter 13 2 6tswua9s(2jx* b ywpqwyt::4.122 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 scalea0uv )y-ydavu8bve 96)hfo c5 :
(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 Fahrenheit scyce05n ee+ (yxale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth z;.fsf a(qz7ynk9aa to+ .*pu 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 combus lb1las ujowuv0o4j 1mm6-x6 rh+4b 8htion engine, air at atmospheric pressure and a temperature of h8-x1jlvub 6mus +01 64roohajbm4wl 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 oxygen at STP using the ideal ry1v np tg*96vgas law.    kg/$m^3$

  A storage tank contain8 wya;1uor w 4 rar19 )v*us;pj2vdsbls 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 contaor2e/ 2mhz6i jins 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.a(5s,llo r6e byzj*2z 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 10e jx1,p m1o9au5.0 kg of argon gas at 385 K?j 11mau ep,xo9   $ \times10^{ 8}$Pa

  A tank contains 26.0 /66it /ninuopli tg, /kg 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 achieves its buoyant lift b. m 5y+bc71t)mnfvgm vy heating the air inside the balloon, which makesvbt mnc )1vmy5fgm.+7 it less dense than the air outside. Suppose the volume of a balloon is 1800 $m^3$ and the required lift is 2700 N (rough estimate of the weight of the equipment and passenger). Calculate the temperature of the air inside the balloon which will produce the required lift. Assume that the outside air temperature is 0 $^{\circ} $ C and that air is an ideal gas under these conditions. What factors limit the maximum altitude attainable by this method for a given load? (Neglect variables like wind.) $\approx$    $^{\circ} $ C(Round to the nearest integer)

  A tire is filled with air at 1g1z0ayh wq,o w2ed3-y 5 $^{\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 bn98kz qyq4qlxact46gl* 2d;$^{\circ} $ C and an absolute pressure of 2.45 atm are compressed to 48.8 L and at the same time the temperature is raised to 50.0°C, what will the new pressure be?    atm

  A helium-filled balloon escapes a child’s hand at t q a 22txqig)21jtyvhg3hi/ql9c36t sea level and 20.0 $^{\circ} $ C. When it reaches an altitude of 3000 m, where the temperature is 5.0 $^{\circ} $ C and the pressure is only 0.70 atm, how will its volume compare to that at sea level?    times the original volume

  Calculate the number of molecules / 2fqnrlnm2wb3tp 21 w6f; r 4xj$m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L?z+h z0(5v nohndv) c1e How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) moles, -v7x smd5l0u*l9jnm i    $ \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 5wbrc *:dhd 4r8.1$ \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 you inhale7r ywsus0l ,ru 6a3jzou8h;4h that were also in the last 8 s,jh4u7rural;0 zo3u shyw6breath Galileo 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 molecule a;utx : tqt5q8s(ve0gst STP? qse5t; vtt: s(0quxg 8   $ \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 kateej( 3 f,n.l08i; gy kz)rothe surface of the Sun at a temperature k;e l r8t,iya)e(gnz0f. j3ok of about 6000 K.    m/s

  By what factor will the )-u60;vgm yp9zefvf-lj 6 aujr +lm9irms speed of gas molecules increase if the temperature is increased fruj9 ajfr6p-lyv fm 9- ;lu60v)emiz+g om 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 f5n id0bd(:uv km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calculate the(fd0v b 5nuid: rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at 20.0 s0iejbb;c /s2 $^{\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 dou/8n.q+78)a 6 uxryyv kuzddyabled while its volume is held constant, by what factor7a8 yxn)v yz+/dua. quydr 86k does $v_{rms}$ change?   

Show that the rms speed of moleculeskhl1zz :tgd14pg l:t6(lrtei7 +b/ ut2 zsc2 s 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 2zqg-cn/rw )ojvb:w3w:,,hb ea e mr/of two gases at the same temperature, the ratio of their rms speeds is vb,3h qnzwejr :/b wr)w,/ m-2:gaceoequal to the inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen molecules chcxfb)x*+nw6 yk mq jjyi) :xc3e:l*0ontained 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 spx zb)zt4(zr wa.lo;a1 eed of an oxygen molecule at 0 $^{\circ} $ C    m/s
(b) determine how many times per second it would move back and forth across a 7.0-m-long room on the average, assuming it made very few collisions with other molecules.    round trips per sec

  What is the average distance between nitrogen molec ayb,rid+-7o kak.yxz a 70*bvules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an aminx hrl0b 4).bk mzj,v+lo acid whose molecular mass is 89 u in a living cell at 3z rv4m+j klb0b.l)x ,h7 $^{\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 pressur5 iy06r co+okplnp 5n0e P of a gas can be written P = $\frac(1)(3)\rho v^2$ where $\rho$ is the density of the gas and v is the rms speed of the molecules.

  The two isotopes of uranium,v d99vem oy3h5o,bt. l $^{235}$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 pressurei:td g5o++lm z, 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 ph c(.4g06p5s yaoj drgdase when the pressure is 0.01 atm and the temperature is (a) 90oy5pg.s r4 0jgcadd( 6 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approxihs 7a/ pzufi :4l-,qtf 4rl9iqt0uy,9wei : pcmately) if the humidity is 50% on a day when the te:t q7, i lyi:rpu4 uqs f9z,9ew4ipct/l ahf-0mperature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a p(-,dk ic* xg9n-f*g pskn 5bjlv u2m(elace where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains 4/8x (lql t wph1xoz,dcpa f-:is 0.72 atm, estimate the tfpoc/dq4lp: wl,za h tx-1x(8emperature at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partiaey-w.2.xdn :an/8 1mwx 8k jkxis2p,x7 qtgl fl pressure of water is 530 Pa and the relative humidity is 40m.syn8d :wx.ag 1j2e7xpl,qx2n fwt8 i /- kxk%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressuxz+/xg6p sh7c re of water on a 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 thx r,w ,t2n2hate water is boiling at a temperat 2nx twt,2rh,aure of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room of volume 68;;/9/ 8 s d+glyjcw2xkwws 1plrgc+q0i6lwjd0$m^3$ 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 xqtf+0 ds2n:xof 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 foc j4tb0r9r +gvgsxo- ;z3wg*xr a glycine molecule (see Table 13–4) to diffuse a distance ofgrg-cx+ vjgx0*4 rb9;3zw sot 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 in-2rmu lj29;nc by t+taterior through tiny tubes called tracheae. An average trachea is about 2 mm lrj- mn tbtc+292a l;yuong 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 measur;xeetz/e kyqrgby617 c: qo)31 qyha8e 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 precise steel tape measure has been calibrated at c-c;+gbk:b k 15loal b20$^{\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 cn9ztq*l+o (f vuha4 bcih, a.r/ank67alibrated at normal room temperature. How much error will be made in a recipe calling for 300 mL of cool wate46alhk zhaf +.7i,u ct(nb9n*o raqv/ r, 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 fm4,i(wcfz 3rgas cylinder is initially 28 atm. After many balloons have been blown up, the gauge pressure has d(3 4fiw,zcf rmecreased 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 m, width 3.zh g3r u 0h6eywo0;tr81 m, and height 2.5 m. Assume the temperaturth w60re;8y0z3gh uroe is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is about onra1 q w 9+io3vqtty* avtc6()ne 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 vacd5/z:gk2 )j y/k vxfhluum techniques is about2z)xvg/ /fyh5d: kjkl $10^{-12} N/m^2$ 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 belowvxyg :l3sbx/v.q p b95 a3)* gwwqx/ch the surface, to what volulbxv*:3vh5x wgw) x3g./9q sqbypa/c me would his lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning f.u;jc en 9.bgdr27bdarom the Moon enters Earth’s atmosphere at a speed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this speed correspond to what temperature? (Because of this high temperature, the no rudaced97gj.bn .2;b se 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 ga) xvku u5l/9q r1qy;2.pxrchas is increased 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 volumei1(hfea6k kb8 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 of atmospheric pressure at the surface of thef ywt es mzp/,4j3(7t6j3gzon Earth, estimate thej 3st7 , (4/m wtzpo6nzjyf3ge total number of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contv r+wduf 7w27jained 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 pressura,r 1zl.r qm(re = 2000 psi (13,800 kPa) a.lr1m,ra( zq rnd at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liquid mercury af+km l,syyk .s9n 5f0et 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 b/:x 38ic07 o 1 l+mtaffylzfqat 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 /b1 ycd v3qbnw*if(5bui-bed .h6e p6to fit snugly around 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 tightly onto a g2-+8n2suxbnmm-ziisfa .t w(h2pi g /lass 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, adopteid55 s/i;:r5 xqr csk gci/j+qd 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*j43n dii) yd u2vu;xz pressure of 195 atm at 20$^{\circ} $C. The volume of the tank is 11.3 L.
(a) What would the volume of the air be at 1.00 atm and at the same temperature?    L
(b) Before entering the water, a person consumes 2.0 L of air in each breath, and breathes 12 times a minute. At this rate, how long would the tank last?    min
(c) At a depth of 20.0 m of sea water and temperature of 10$^{\circ} $C, how long would the same tank last assuming the breathing rate does not change?    min

  The escape speed from the Eartie cmhz0v79i 6wxti m1b-:y904vru eb 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 lid is suspendq(k1 fw *2wv mpchc/fx3zsks; - i*:v 5xu;amyed against gravity by tennis balls thrown vertically upward at it. How many tennis balls per second must rebound from the lid elastically, ; s* av23suvw(mfw-c h f ;/ x:5*ciykkmpzx1qassuming 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 (buzcc8i25 ee x 8w;o-yspherical) 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 o-wi;bzc58xuy2c8 e eas 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 folm 4dzi9fqpx1mxrr4) rq5jm/ *lowing two days: mp*qd 1)rxmq454z9/rx f irjm
(a) a hot summer day, with the temperature 30$^{\circ} $C and the relative humidity at 40%;    Pa
(b) a cold winter day, with the temperature 5$^{\circ} $C and the relative humidity at 80%.    Pa

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

  Estimate the percent difference in the density of iron at STP, and when it is v38lm 5yk.btmv4e 3krjfj 4m 6a solid deep in k5vt3 ykm 44efl8.r6jm3jbvm the 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 za2xzu5 w1d0s show that, for an ideal gas at constant pressure, the coefsdx2 1auw05 zzficient 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.