Which has more atoms: 1 kg of iron or 1 kg of aluminw m,y*.n mjfir,dn3 x(um? See the periodic table or Appjy(3in,fd.m wxm n,r *endix B.

Name several properties of materials that couldq;dho ; snbl:y.s k7e2 be exploited to make a thermometer. lbn :s;o2;ydqk.e sh7

Which is larger, 1 C u :rjafp 3+ul/$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thema apba6hopq 2g)- lxr2 pbq67 (/2fzarmal equilibrium with system B, but B is not in thermal equilibrium with system C,)qaxb6p(ofphl6z2 2/bpg aqa am-7r2 what can you say about the temperatures of A, B, and C?

A flat bimetallic strip consistsb d0 2o5 lzx/)dcsc2i /9hbo1nflo k4a of aluminum riveted to a strip of iron. When heatefol b1a2sxi l)dn/ 5 0b4ood9/kc2c zhd, the strip will bend. Which 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 dexevbno 1-c ox1 +yy 7ovdh-l(j-7.klinear 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 simplzvm/ t-+/8x zobbg1bye 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 mer -1tzzb/ob8v/bxmy+g cury 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 ha0igt rzzrglvyp j0r9 *4.kt 06ve a section in the shape of a U. 0 y0tk6zt0gvrr.jzlg94*ri p Why?

A flat, uniform cylinder of lead f 9ere8e6h,vdsloats in mercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thez.n,hq)y l ,ucnq* wp2gsx tc/f50ph ;rmometer is first placed in a hot tub of water, the mercury initially descends a bit and t )sz c0x*5ny.pqu,,th fcgpnw2/qhl;hen rises. Explain.

A glass container may break if one pe(pg4g19is fv . x:)xjd,ulooart of it is heated or cooled more rapidly than adjacent parts. Expl9vosjgf.u)i41dp eogx x (:,lain.

The principal virtue of Pyrex glass is that its coef3iqh; jo.ncb 1/ u1kie;uecjl.h, 5hz ficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise tel5uzejbj;h/;3cnh,kou h11 i..qc i o the increased heat resistance of Pyrex.

Will a grandfather clock, accurate at hid+yc-do.pv0eai.6 * l+hx k 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 c .6yuhepk8il4 ause its bottom and top to bulge so badly the can willyiuhlp6k8 .4e not stand up. What has happened?

When a gas is rapidly compressed (say, bys 1fjt*lpt,/u pushing down a piston), its temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperature using the kinetic theory, p 1*futjls,t/ in particular noting what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force on an aluminum sph. mbo+ (gk8v6 ftvuk1lere submerged in water increase or decrease if 8 btkf+v6k l.(omugv1the temperature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theory and the relatiox4 g9 e , ,+dfprpeo.x1ff)rqi-ud wx3n between average kinetic energy and eff, 9-fp)xi +,owq rxdp4r.dg u1x3ethe absolute temperature.

Explain in words how Gay-Lussac’s law follows from ktyoh7)0ead 4 c*ks z6ainetic theory.

As you go higher in the Earth’s aozlad n4b9/(o4 h lu(6i5p qmstmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed an p r t*h1,qik o,pjw5c2object 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 2ij tokppc1r wh,q, 5*smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly tq2 p-jh( pmb8o*8y;uw 7yddd rhan water at room temperature. What can you infer about the molecular prohmr -;78ypjb2 duqw( 8 yddop*perties of one relative to the other?

Explain why a hot humid day is far more uncomfortable than a hot dry day (eab43u: pjz tnu)pm+ at the same temperature)3t:pa+ubp zm u (n4je.

Is it possible to boil water at/1ejtw7j ba k;1 l(fkjg 6 gr)tp0t0fj room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is ft 9dg(i3c)d t)obzi.the same but the humidity is different. Which is mico9 gt.i )(bt3ddzf)ore dense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap of an overhv7ls,lpmxq :u znp5 px /:;oo6eated automobile engx npp/u;vl::,l5m7zxo o6 ps qine.

Why does exhaled air appear as a little whiteu0d s wgunh /f3r2/4r naltj94 cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram coppeozb+x,o 0k-ruelps83mc;* pfr penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare to the number in a vh l3/tn*iv+k silver ring of the slvkit *n3 /h+vame mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is ofter4dymh p: x6o5n taken to be 68°F. What is this on the Celsius scale?6o prd 5hy:4mx   $^{\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 recordeu iie1 3t*roc u1,cgs,d are 136 $^{\circ} $F in the Libyan desert and -129 $^{\circ} $F in Antarctica. What are these temperatures on the Celsius scale?high =    $^{\circ} $ C
low =    $^{\circ} $ C

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

  In an alcohol-in-glass thermometer, the alcoh fo8h/e/ktxa-ol column has length 11.82 cm at 0.0ktx a-ef/ 8/ho $^{\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/:dbuu8hh i; m 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 ap/.crodrc;rov 2 w08wc proximately 300 m tall. Estimate how much its height changes rcocwrd vw0o82cr.; /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 fitvcml*xx-t 0+b, rivets that are larger than the rivet hole are often used and the rivet is cooled (usually in dry ice) before it is pla+ xlm*v0cbt-x ced 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 /etr, k ad,myg )o;ul3at 4 $^{\circ} $ C is $ 1\times10^{3 }kg/m^3$ What is water’s density at 94 $^{\circ} $ C?    kg/$m^3$

  A quartz sphere is 8.75 cm in diameter. What will be its change in volume if s u2s1tjyuiysj,6 3 .ait is heated sau, .i36jyss2u1ty jfrom 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is fillqpdk+bpd2p55viqvf: (p n q*4 ed 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 wateru:z vt wncknx0,9(- c/xp9gsj 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 ouclc.tcy1yzj 0az/e9l , ei:.:tr+zto be placed in a ring made of iron. At 20 $^{\circ} $ C, the diameter of the plug is 8.753 cm and that of the inside of the ring is 8.743 cm. They must both be brought to what common temperature in order to fit?    $^{\circ} $ C
(b) What if the plug were iron and the ring brass?    $^{\circ} $ C

If a fluid is contained in a long, narrow46wqtb, t fek/ vessel so it can expand in essentially one direction only, show that the effective coeffbe 64wt ,fqt/kicient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the.7onnk. ng m;ahh6 p6 st9,qwj 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 of linearvh6tbak 4c.n )a;(ow2 i3az77c. gydvcgp(bf expansiona (nz .bt gyk)7 co3wb vg2.p(;cva4diah7fc6 $\alpha$ 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 s jjl8tk4i1n 8t4g e9 abvr/c(jolid, $\beta$ = 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 cl6m n1 ,/89aqkmpkvia cock is made of brass and keeps perfect time at 1qkma,ki p m8a6/91 vnc7 $^{\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 th8p/zqt f 7ois3ermometer has an inside diameter of 0.140 mm. The bulb has a volume z 7q3f8o its/pof 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 cyv xk)c+i sk rc/n;g79( g*cvj6gc8cke lindrical wheel of radius 0.41 m is rotating about its axle on frictio*c(vkrn 8/ccce 76gkg 9iv;xkc+ j)gs nless bearings with angular velocity $\omega$ = 32.8 rad/s If its temperature is now raised from 20.0 $^{\circ} $ C to 75.0 $^{\circ} $ C, what is the fractional change in $\omega$?   

  An aluminum bar has the desired length when at 15°C. How much stress is require94syn2geo .wt6r7vto p1 gw,xcdjr1 ;d to keep it at this length if the temperature increases twcxg,67to2r o1t1 pgyv9 d j4s.ne;wro 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-sectional aq5qz62,1ybxw f: psx; e qsmb)rea 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 134.1lhibc, :frsdrpsz(0j 4zj+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 Kelvitr 8n4ukj kiv* ski,s1nb+*(tn 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 Fahrenheit sce3wnm so+ e td;a;d96jale?    $^{\circ} $ F

  Typical temperatures in the interiog2va rstca - v,oz x/dq(841xnr of the Earth and Sun are about 4000$^{\circ} $ C and $ \times10^{6 }$ $^{\circ} $ C respectively.
(a) What are these temperatures in kelvins?    K    $ \times10^{ 6}$K
(b) What percent error is made in each case if a person forgets to change $^{\circ} $ C to K? $\approx$    %(Round to the nearest integer) $\approx$    %(Round to three decimal places)

  If 3 $m^2$ of a gas initially at STP is placed under a pressure of 3.20 atm, the temperature of the gas rises to 38.0$^{\circ} $ C. What is the volume?    $m^3$

  In an internal combustion enh5wxv+ :av5q +wuw6a ggine, air at atmospheric pressure and a temperature hg6 a5 wwa++wvxuv5:q of 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 9qz4uvhc*xap3t q0,zz mm5c 5at STP using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of nidtf:k 5au 2r8jtrogen ($N_2$) 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 containholn*j6p 6pmt. t1id68(wo zg s 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 atoqwxgmx 1 ;)4b 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 holding 105.0 kg of argon gas ezbjgnb;*:wd)2x2,+k a5mf t oos( nzat 385 K?k2bnd z() jws :to+f5*ez,2a;gmbnxo    $ \times10^{ 8}$Pa

  A tank contains 26.0 kg of 5a6rpcx 9f7pdorr1t ;$O_2$ gas at a gauge pressure of 8.70 atm. If the oxygen is replaced by helium, how many kilograms of the latter will be needed to produce a gauge pressure of 7.00 atm?    kg He

  A hot-air balloon achieves its buoyant lift by heating the air ins 5btytmj+*f xx- .6acysrv2i3ide the balloon, which makes it less dense t xc6y5 ay3xms.v2* rif +-btjthan 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 a/fn hda2v7(9 c-9mlkbi: tgj n+nmcr:ir 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 vp9ykks3ww,wt5w m,+at 18.0 $^{\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 +if;- ttvtg y1at 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 zt/ ok71-sj /dzllr -a/ $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water r6rex/j 08zasywgybdt5 -,9lare there in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) mol g 53fwk,l-izges,    $ \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 +w 6jpsd:nwqs e7 8ts3cix7f; 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 i.f+uc0j e g.;7iuacqe7qs5k1 cw c(j each 2.0-L breath you inhale that were also in the last breath Galileo took. [Hint: Assume the atmosphere is aboui(sq ec .0ge5 wk17q cuc. fu;+ca7jijt 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translatiomu j2zdprf,9. nal kinetic energy of an oxygen molecule at ST.p ru,jfzd 29mP?    $ \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 hej4 :ub2h*vs uqd 1ae,jlium atoms near the surface of the Sun at a temperature of about 6000 Kj,1d2bqaj*e :s4v u hu.    m/s

  By what factor will the rms speed of gas molecules increase if the tempera (ffs/1l-aeki ture is increased fif1(-ska e /lfrom 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 speewzazxg+/ fh6 ; ckx3ghs q+;8bds, given in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Csxcwxq f+3hg6g+ ka/z 8 ;hzb;alculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of moles,a(g,aapb9 xcules in a gas at 20.0 $^{\circ} $ C is to be increased by 1.0%. To what temperature must it be raised?    $^{\circ} $ C

  If the pressure of a gas is doubled while its volume is held cons.piuv ya +jbx4z6g x2j*m;7letant, by what factor diu4xlj vaz672ybg*j xe + m.p;oes $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is ql ib2wr;v8uwkakt4y 04hf* wb 2pd6( hyq+b3given by $v_{rms}$ = $\sqrt{3P\\rho}$ where P is the pressure in the gas, and $\rho$ is the gas density.

Show that for a mixture of two gases at the same teg.9 brydzbc *+mperature, the ratio of their rms speeds is equal to the inverse ratio of theb*ygd.9 c+bzr square roots of their molecular masses.

  What is the rms speed of nitrk32n)c1 ddub logen molecules contained in an 8.5$-m^3$ volume at 2.1 atm if the total amount of nitrogen is 1300 mol?    m/s

  Calculate (a) the rms speedzqzc ui*e **h( bwmghe.0o;n1 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 molqs7,,0 6ryvw t3i -hhteendg n0w7* qnecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms spey2*zto* 2wk 9q*wz) zccf ,syn80 fviped of an amino acid whose molecular mass is 89 u in a living cell9is)w*z y0cfc2 z8of* zknp q2*wy,tv 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 by.hxe4- ag1 )x2qal7)n wwi0qma0 fhne 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 urilg8i uv +p(gv/zx7u(:y4f cqanium, $^{235}$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 pr8 99: jc:ucvnc 6bhueressure, 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 is6s, b ) urk;nuxt7cu8uyewy 7, 0.01 atm and the temperature is (a)k77c8yrt ub; unyu, ,xwu6 es) 90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximato9 iv:5a3gl khbks0cr f(k2n3ely) if the humidity is 50% on a day when the temperatur3a( 9lco53ikb hfg20: kv knrse is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water boij3lohsp;o/un kh; 7k;ls at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mon0cyd2n 6zfmajjeoyyf6 olz8- 2 ,4 n4untains is 0.72 atm, estimate the temperaj48oyy4 6-moj,z elnfy df 062a cn2nzture at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pres wo f3vwr5pc h/6aeoul0,8 feh es68e:sure of water is 530 Pa and thhe3 pva50 f e8urf/w6o 6,osechlew:8e relative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the temperatuxcu 0 wzv)48exre is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure i a91(opxz)0 z-3stj/ zxmcbesnside a pressure cooker if the water is boiling a01s so/t3zbmjx(exp9 - )zczat a temperature of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room of volum3hlcb:w ml;jv /rrp/ /e 680$m^3$ at 25 $^{\circ} $ C is 80%, what mass of water can still evaporate from an open pan?    kg

  Air that is at its dew point of 5s :zdg+;q6-f f7pxqs,d lpc iu+(ly5n $^{\circ} $ C is drawn into a building where it is heated to 25. What will be the relative humidity at this temperature? Assume constant pressure of 1.0 atm. Take into account the expansion of the air.    %

  Estimate the time needed for a glycine molecule (see Table 13–4) to difkztm0a/ o/ yc3fuse a distance okzy0a/ mc3to/ f 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 tfc)hp 4-ab8 rihc,z) yo the interior through tiny tubes called tracheae. An average trachea is about 2 mm long and has a8bpc)-z,) yrci4fhh 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 measqrnh7lg*) cdpwx h*c 9r k, y-y.mr-+fng/gg6ure 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 measur7 .d1wh6nu xfde has been calibrated at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A Pyrex measuring cup was calgs0k0+12m dybaldokj d t9t(;ibrated at normal room temperature. How much error will be made in a recipe call( 1k0dd0gly9obt2 +;msjtdka ing for 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 isz y; 6- ;- 9igs0nppoxhcbn5rv initially 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 cylinde- v5pg;r9;zybi 6-cnn sx0 ophr?   

  Estimate the number of air molecules in a room of length 6.5 m, width 3.1 m,7 ro3b0ortn1w 0 tj05gaii.ru and height 2.5 0r 3tui1.o7ai jrno0 gb5wr0tm. 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 is about oebk1yd j6ax:.3yz,hy 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 usint/ifomed 3fu/xqqgofpkn 1: e ( .(;,kg the best available vacuum techniques is about gm q/oufe(po1;x:kf e/ i.fdk,3(t nq$10^{-12} N/m^2$ 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 lun8:d*axv sfs*tq w2a0rgs to full capacity of 5.5 L when 10 m below the surface, to what volume would his lungs expand if he quickly rosewdtvq 2x*sf0: as*r8a to the surface? Is this advisable?    L

  A space vehicle returning feb,)j4+j dqyk ;tmm/hrom 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 nose of a space vehicle must be made of special materials; inmt),d b ej/ymh;qj+4k deed, part of it does vaporize, and this is seen as a bright blaze upon reentry.)    K

  The temperature of an92 zrh -h/c3wmxd:; aiks8kzb 5+ xmhm ideal gas 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 volumejjy- x726hm2cqubr -w 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 the Earth, estim0mxkm k b)5m qbiia)a9 -1q7wyate the total number of air molecules in the Earth’7 qiam iq) 95wkbyk)-bam0x m1s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogey+y/nfuhe sww *8ia 1mccv6(8 n molecules 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 hospitazd hf0yoh4 ;xc +5etody.5b x/l has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow 4x /zfhx0o c t5bd+y.ey5 h;dorate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liquid mercury a( j+. zdlo,i8p3e vpvft 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 erl;z8x p1ff83k pnh(5qw6 pj0$^{\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 6q.7ft,gtn iuo,2x3 e,csaho 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 ont9t es41td3zs lo a glass jar at 20$^{\circ} $C. To help open the jar, it can be placed into a bath of hot water. After this treatment, the temperatures of the lid and the jar are both 60$^{\circ} $C. The inside diameter of the lid is 8.0 cm at 20$^{\circ} $C. Find the size of the gap (difference in radius) that develops by this procedure.    cm

  The first length standard, adopted in )rs1dh9 yaa7cthe 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 full86e0r8r dt 9pwlakl /my charged, 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 Earth is kn .0rslgcqe 5+rfhde-,7- go $ 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 susuiz h;;6 ylc/ipended against gravity by tennis balls thrown vertically 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 thrownh ; ;li/zc6uiy at 12m/s   balls/s

  A scuba diver releases a 3.,;-yvijjrx,z uoy.ck24* sh n00-cm-diameter (spherical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the air behaves as a perfect gas. How large is the bubble when it reaches tr 4,xu.okjn h, cvys;-zjy*2i he surface?    cm

  Calculate the total water vapor pressure in b /y;wztx.og4u g*u 2fthe air on the following two days: woytz./ g2fu gbu;x4*
(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 avo r6dbs )lo 5,jagf8, solid deep in the grb as5djo),olv68f, 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 show that, ko(pohay 8qnv8g/ca 4dt (8/hfor an ideal gas at constant pressure, the coefficie8h(y ogck8o p/8( ha vntq4/dant 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 consddc.jm 6+0 q;is7d enktantly dehumidify their cellars to prevent rot and mildew. I cd d;k 0m+e7si.d6jnqf 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