Which has more atoms: 1 kg of iron or 1 lzd,5z 7k: k7hnb2 khrkg of aluminum? See the periodic table o7rkd5nk,z:b2zh h lk 7r Appendix B.

Name several properties of materials that ch0ljxgo2 pifky827 )hould be exploited to make a thermomet ) o ykhgf7i0jxlhp822er.

Which is larger, 1 C b9-ue)d x-khv$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, bb.1ft1usro t1ut B is not in thermal equilibrium with system C, what can you say about the temperatures of A, B, and1 .uotrftb11s C?

A flat bimetallic strip consists of aluminum riveted +xaxylz5y*j 0to a strip of iron. When heated, the strip will bend. Which metal will be on the outside of the curve? [Hi*0xayjy+x 5zl nt: 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 coeffic-xust, im4z) dient 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 thermostat used to control a fu znaege 4kk77,rnace (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 diffezk,n ge7ake47 rent temperatures.

Long steam pipes that are fixed at the ends often have a sectionvk.n7bj,q nn6 k,*cyh in the shape of a U. Wh,k,bc7jqn* nn6k vh .yy?

A flat, uniform cylinder of lead floats in mercury at 04 rmw m0)jkma; $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometer is first p gckdyz /.u-an**jwxz u1x/p*laced in a hot tub of water, the mercury initially descends a bit 1ugz ucp * /wk/- x**dzxj.anyand then rises. Explain.

A glass container may break if one part of it is heated or cooled more rapidl+wh+ 8ub7a1ieq lv*d+ fs. nhly tqvs1fhli+d 8*a.b+ w7hen+luhan adjacent parts. Explain.

The principal virtue of Pyrex /drbb m6*l;nfcl 0 ;p ir:of2aglass is that its coefficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rispr*/;afo2i c;lbm dnr:l0b6 f e to the increased heat resistance of Pyrex.

Will a grandfather clo4 b+1-pjd epcrck, accurate at 20 $^{\circ} $ C, run fast or slow on a hot day (30 $^{\circ} $ C)? Explain. The clock uses a pendulum supported on a long, thin brass rod.

Freezing a can of soda will cause its bottom an;irnbc5fn t9 1rzdz38 om cuqg;w +-7wd top to bulge so badly the can will not stand up. What has happened;+ 79 ziwo zcbr ntwd3c15m rq-fgn8u;?

When a gas is rapidly compressc1,4oauho+ vtgr:vvxl b:. 2 sh vcq4ubm+ (o;ed (say, by pushing down a piston), its temperature increases. When a gas expands against a h1: g,( :cv; ruhvasblu4.+ octm 42vv o+qboxpiston, it cools. Explain these changes in temperature using the kinetic theory, in particular noting what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force ont99ot w*kftaae:q 03ha e31z o an aluminum sphere submerged in water increase or decrease if the temperature io9q 3f w*eo0az 3k h91:teatats increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law followo3rn7w 1o/ac x+ulhx-s from kinetic theory and the relation between average kinetic energy and the absolute temperr/w - l 7xohnoxcau1+3ature.

Explain in words how Gay-Lussac’ lwrex9hl9,a(a3p 1c0vw a :54eq vculs law follows from kinetic theory.

As you go higher in the Earth’s o7v5zlu k.2dd atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speef6fasbdnh.;h xt +c:)/ spq (ld an object must have to leave the Earth and never return. The escape velocity for the Moonqs;f )pc(+lafb./dth: hx6sn is about one-fifth what it is for the Earth due to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at tqy1x4tf r;d vj8d eo()d/vt +room temperature. What can you infer about the molecular properties o8/ qyod dx4)+ ttvfvjt (e;rd1f one relative to the other?

Explain why a hot humid day is far more uncomfortable than a hot dry daye;og bl:myh(;dbzw97 at the same tempera9;l yhd wbo;z(7: mgebture.

Is it possible to boil water at room temperature (20 fl .nbxnu;f4gs*j47r $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the hu9u c()gw 6rx 9tg9k)3c/*hpzaoyn whumidity is different. Which is more dense, the dry air or the humid air at thehzow/ux p h9tgc)n6 uc9r(ayk 3 w9)g* same T? Explain.

Explain why it is dangerous to open the radiator cap of an overheated auto(:og;9:ib-qk4omxnb g cxv1mw es +9dmobile eng1oo g:cq99vwg:neb -dm 4 k+sbx;x(imine.

Why does exhaled air appear as a little white clozl 7 t2cy-3xpyud in the winter (Fig. 13–28)?

  How many atoms are there in azo.- :z73pdmctw ft/z(8dtyc 3.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare tomk) p:pbd,5 ep the number in a silver ring of kbppd5)me: p, the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this on the Celsius scale y;v 6m q32 4f;vurumx*/edehz?hv/uz34 f ; ed2ymv*m u6eqxr;   $^{\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 recordeiec)x;ddo ,d 8d 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 xj.z28 cjpe8hcolumn has length 11.82 cm at 0.0pjhx 2ej8 8zc. $^{\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 bu8:eh 8qmnb xmvmd- q5+ilt 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 aw6o(clc:sd(gxj al 23tz(g1 spproximately 300 m tall. Estimate how much its height changes between July (average temperature of 25°C) and Jal:wo(g 2 da(s 1cj 3xgtl(c6zsnuary (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; udn9s78 29sa bylswc, 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. A 8bs9sn w2y l7;dsua c9steel 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 at6pln7 :o/yf7spr2ufp 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 mnkp:,e/9 qse in diameter. What will be its change in volume if it is heatenpmkq:9e s/,e d from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350.0 mL of water at 10ir3(j/h jg. 0zc6jy lf0.0$^{\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 hun(g 78f;zo9:czf ti20 $^{\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 rio:km kpni 2h1pq:+ dg)ng made of iron. At 20 $^{\circ} $ C, the diameter of the plug is 8.753 cm and that of the inside of the ring is 8.743 cm. They must both be brought to what common temperature in order to fit?    $^{\circ} $ C
(b) What if the plug were iron and the ring brass?    $^{\circ} $ C

If a fluid is contained in a long, narrow v 6lqjgbq)00;ccrf9m hessel so it can expand in essentially one direction only, show that the effective coefficient of linear expansion is approximately equal to the 96 hlcjc)0m0qfqbg r;coefficient of volume expansion $\beta$.

(a) Show that the change in theawa8g0f1f 2j f 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 len:e fsi7j*1ok ygth l and width w has coefficient of linear expansioy7ij e*s1:k ofn $\alpha$ 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 isotrop6e9uv;aic(y su ij/) eic 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 o ui 4l:.w9u-lq,s4v uzc;ydmo f brass and keeps perfect time at 17 -uo9. lu m;q, dwus44z:lyciv $^{\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 0.140 mm. The bga/z 5l/f6tt*8k xa f5dj5vs(du+xgu ulb has a volume of *l5u5f /( 8xv t ak5af/dsux6ztjdg+g 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 cyl-t j5w siwml98indrical wheel of radius 0.41 m is rotating about its axle on frictionless-jls8ti5wmw 9 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 th1y 1rr9tvzgck d;,tqp3xa 18l e desired length when at 15°C. How much stress is required to keep it at this length if the t v1ld;ck3artrzyq91 xpg, 81temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-sj ;pgq.hkoq1me, ,re:ectional 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 cm at9am (*hcnrd1kpbq( ko (be) k)76u ouv 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 tempei 2p5px6-ho xzratures on the Kelvin scale:
(a) 86$^{\circ} $ C,    K
(b) 78$^{\circ} $F,    K
(c) -100$^{\circ} $C    K
(d) 5500°C,    K
(e) -459$^{\circ} $F    K

  Absolute zero is what temperature on mkic7;/u7p pj the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth an7 d. hoakd03zj gey(p*d 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 pressure and a temp l,ms ,9bi.zuz*xfk pir m);tc,c5kt0erature of abk*mulrmctckps 5,)9 ,zi; 0 iz.bxf,tout 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 STPqu7g /i)2q e( 1mzo)ca5eijiw using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg ofenzp5h m*5hlq 3 bs+a8 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 contains 18.5 b4)0-/ax 2 jm trgsyyqst/6sukg 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 itc 8af.-6hufl-p1mtoos z a03 s 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 inside a 35.0-L container hol-(,-gxhu*mg ssmg6b r ding 105.0 kg of argon gas at 3 *gg6 ms-ubs -ghxrm,(85 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg of bgoo.76d q6 itba r.2 pd5zwxh23zk9t $O_2$ 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 sh. y ln*)z/z-lyo*rk its buoyant lift by heating the air inside the balloon, which makes it less de osy/yn * lrk).*-hzzlnse 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 wittqx24:cdikseh*g q75ej.o *vfi , b*yh 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 18.0sgxpr. vl+7+j8x 7so2 sl bsi( $^{\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 fi+2 lfuqb*;jj9pf;c 1 /algosea 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 moleuy . fh7h0jl:ibvqx*hqx6b (1 cules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How many molecules?a/ l3t,wjfvp*    mol    $ \times10^{25 }$ molecules

  Estimate the number of (,*gsru 1iqx,b8ql j,ua) 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 volummomln7by4 :v .e 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 2.0-L breathd s ;hwhon3h3m0uy*e i4haa,+ you inhale that were also in the la, ihmoad* wy 3n0hh h4;3a+eusst breath 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 o8x(.5gldzskx q:cp5 q*ud 3yof an oxygen molecule at STPx 38pqc*oz: 5lsquy x5(dkd.g ?    $ \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 heliump+d u,jptpl,5 atoms near the surface of the Sun at a temperature of about 600ulj,dp ,+ 5ptp0 K.    m/s

  By what factor will the rms speed of gas molecules increase if th0d0g gm2mq 6qpe temperature is increased fromg0gmq6q 0dm2 p 0 $^{\circ} $ C to 100 $^{\circ} $ C?   

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

  Twelve molecules have the following speeds, given in units of km/s: 6, 2, 4, :0 s y9m dl(qii-ob8ogq r3;ygh7qn u/6, 0, 4, 1, 8,irq i9 8b(3go0 my7g/:snuhd oq ly-q; 5, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at 20.6c imh,c- 9fub0 $^{\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 whoi tsx9swxhv28m gy7 n3 *r(:pile its volume is held constant, by what fact3vom7 x r:t9gxi hs 8ws*yn(p2or does $v_{rms}$ change?   

Show that the rms speed of molecules in ai8 /mgt llj8,n 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 t1(6w an)vacp peb;8 oawo gases at the same temperature, the ratio of their rms speeds is equal (aa;) bv 86pwconap1e to the inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen mol s3ql7l ;a3m uy7.mqh8wv.dsvq*f4 l cecules contained in an 8.5$-m^3$ volume at 2.1 atm if the total amount of nitrogen is 1300 mol?    m/s

  Calculate (a) the rms speedd qh(4k lix4i: i9)fja 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 molecubdikuic-te-1b 4 5f-ples at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed o :b+yn.1x6hill4fixsg ) bp5b 2xit1af an amino acid whose molecular mass is 89 u in a living cell aa sb px:htn i+1i6 xx52yl4b1.fgil)bt 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 writry ( +pjasld+hn;/7b pten 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 uraniu gw07jkkuc.g(-t3j gu6bd+bmm, $^{235}$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,7fv)gzy )he e; 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 pr60 4h k n4te4ygy jm;e3x4fcngessure is 0.01 atm and the temperature is (a) 0ejm64tn;yy4f geh k43cgn 4x90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidi2m iveq+s gr;lxce8+9ty is 50% on a day when the temperate rm 2sgi;+lq +v9cex8ure is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where mn + xt5a+4rgfwater boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is 0.72 atm, e cwz+bdd2a6 9o o61fbhstimate the temperature at which wat b+c6o26ah1f bwd z9oder boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when; b ymr4o8phh3 the partial pressure of water is 530 Pa and the relative humidity ;83rhy4phm obis 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when thevi-; rrbd/o:v7+t xati6 fqf7i;qgj * 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 boiliii.add klah+( , p-5+rlvt*aa ng at a temperature of 120t- apd,ii kal+ald (*h+v a5r. $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room of vol stzii.b 0d:.ssf m(:nume 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 5n l +,sam-,qxl $^{\circ} $ C is drawn into a building where it is heated to 25. What will be the relative humidity at this temperature? Assume constant pressure of 1.0 atm. Take into account the expansion of the air.    %

  Estimate the time needed for a glycine molecule (see Table 13–4) *:u6 h j.3wvdt qrchvc;3 o6ni p62qlkto diffuse a distance 36rli.vot2j3w6 :dqv*q; knu6chhcp of 15 $\mu m$ in water at 20$^{\circ} $ C if its concentration varies over that distance from 1 mol/$m^3$ to 0.4 mol/$m^3$ Compare this “speed” to its rms (thermal) speed. The molecular mass of glycine is about 75 u. t $\approx$    s ([color=rgba(0, 0, 0, 0.85)]Round to one decimal places) $v_{diffuse}$    $ \times10^{ -5}$ m/s
$v_{rms}$    m/s

  Oxygen diffuses from the surface of insects to the interior thrq 9.vk/-:yd dcxrpq .0e7uyeuough tiny tubes cax . yeqq:.9uv/c0ek dyp- dur7lled tracheae. An average trachea is about 2 mm 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 c,ffdp (imu b 7f..0whmeasure 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 bea1v say3 i3ktbfy/ 85xen 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 w wnd.rryq7 zy/*ut39* kbh4fras calibrated at normal room temperature. How much error will be made in a recipe calling for 300 mL of cool water, if thebfd**urk t9.3n yqrwry 7/zh4 water and the cup are hot, at 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in a helium gas cylinder is initially 28 atm. After many bal(b:q5gm; y ltg3c3 dlsloons have been blown up, th: ;ql3d3g5glstcb ( mye 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 m, width 3.1 m, andcy7 t,uq o/g* els9j*sqc /*s*et9oj l,y7gus height 2.5 m. Assume the temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter 7 gyvuzq.w3jl 5wuuv639d; ka 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 bvu1bp.usyq0, th,4 xu z(c8 llest available vacuum techniques is aboutb.c1,sply4q u th ,l08vuxzu( $10^{-12} N/m^2$ 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./fy uphs fhy9h;;36 gnb2q6/qpld, qz5 L when 10 m below the surface, to what volume would his lungs expand i; ;nqz6q9pqhd /6h /f3lpsugy ,2fbyhf he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from thqxj mi/8z cv(;e 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 correspon (;mcivxj/zq8 d 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 incv6 78tzu (pjnfreased 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 volumevi37jenar: w;k z3.)t 1 bjxjid6w jn: 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 in.hpbjc70 hf5)gcy - zl/irp: dpy46the Earth, estimate the total nu45id/7)-j zphry yfc:.p gpcbh i6l n0mber of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules to - ce i g/;o93*h5dfu:qcmrrcontained 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 =n1 cq 7fliliedm7 7-p f/(+xpp 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmosphe- nfp/xi q 1p7ml(cflp +7dei7ric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of(:o m:r 2vhvxk 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 0 tn4 jrp :d(:p)ppi+bg$^{\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 atk1e g375l glnm 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 o: 6zqjx/cia+ 1j chld4nto a glass jar at 20$^{\circ} $C. To help open the jar, it can be placed into a bath of hot water. After this treatment, the temperatures of the lid and the jar are both 60$^{\circ} $C. The inside diameter of the lid is 8.0 cm at 20$^{\circ} $C. Find the size of the gap (difference in radius) that develops by this procedure.    cm

  The first length stae3mr b *z /.svjezr/i5u.nhk7ndard, 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 charge )/g.aayzcg9sn7vr/ +sx;hj cd, has a pressure of 195 atm at 20$^{\circ} $C. The volume of the tank is 11.3 L.
(a) What would the volume of the air be at 1.00 atm and at the same temperature?    L
(b) Before entering the water, a person consumes 2.0 L of air in each breath, and breathes 12 times a minute. At this rate, how long would the tank last?    min
(c) At a depth of 20.0 m of sea water and temperature of 10$^{\circ} $C, how long would the same tank last assuming the breathing rate does not change?    min

  The escape speed from the Eart8ekln5 -4v atljpy+.gh is $ 1.12\times10^{4 } m/s$ so a gas molecule travelling away from Earth near the outer boundary of the Earth’s atmosphere would, at this speed, be able to escape from the Earth’s gravitational field. At what temperature is the average speed of
(a) oxygen molecules,    $ \times10^{5 }$K
(b) helium atoms equal to $ 1.12\times10^{4 } m/s$    $ \times10^{4}$K
(c) Can you see why our atmosphere contains oxygen but not helium?

  A 1.0-kg trash-can lid is suspended againstyz4fryio n e s, j/w25ychs4/. gravity by tennis balls thrown verticallyn z/f4w ,4 o2 y/.sieyjch5sry upward at it. 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 ar3 8pyz6 ,wyns 3.00-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 bez,w s3 8pryy6nhaves 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 yzdh /fog,o(v.eu; b1following two days: oh1;v, b/z.efguo(dy
(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 o5adk a5lje );rf iron at STP, and when it is a solid deep in the Earth where ;k)r eaj l5da5the 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 shozp6nbl3(g 6mg 9ns*7 e8rdt ufw that, for an ideal gas at constant pressure, the coefficient of volume expansion is equa 3(8 n g*fu6lsrnmtbe6d 7zgp9l to $\beta$ = 1/T where T is the temperature in kelvins. Compare to Table 13–1 for gases at T = 293K (b) Show that the bulk modulus (Section 9–5) for an ideal gas held at constant temperature is B = P where P is the pressure.

  In humid climates, people constantly dehumidify their cellars to preve1y 2 e7pds3/nigumt,8oxv t:unt rot and mildew. If7g/iuoun sep3xt8:y12v md t, the cellar in a house (kept at 20$^{\circ} $C) has 95 $m^2$ of floor space and a ceiling height of 2.8 m, what is the mass of water that must be removed from it to drop the humidity from 95% to a more reasonable 30%?    kg