Which has more atoms: 1 kmbs548xi r sjrs6aq; 5g of iron or 1 kg of aluminum? See the periodic table or Appendix Ba4;56r5sirjbx msq s 8.

Name several properties of materials that could be exploitvf+be 4 ,82pfzu per(rpe-9n hed to make a thermometer.2-e9fp8 f z+uv 4re ,brhpp(en

Which is larger, 1 C gey7fx5nl kz z00td9,$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with se 6r7u y15w9k-oumd8gdgl c)6xlp/oiystem B, but B is not in thermal equilibrium with system C, what can you say about the temperatures gylg d9xi6cu6/urlok)1m-p 87dw5 eo of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to a strip of iron. .+el db 16koq7/d mmbrWhen heated, the strip will bend. Which metal will be on the outside ofqb/m.ok ed l 7b+rd61m 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 linear expansion be7-l7mies 1l $\alpha$ 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 r .fcc9qdpix jht7yn87+2ru7 control a furnace (or other heating or coolf2i.xr8jdqc r79cynt 7uh+p7 ing 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 temperatures.

Long steam pipes that are fixe;z3qinrkr l () 5r(xdud at the ends often have a section in the shape of a U. Why?rldkqi)u(rxr z3 n; (5

A flat, uniform cylinder of lead floats :n)k v.k(m npb5cg-rlin mercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometekz k(4cdby- 2gr is first placed in a hot tub of water, the mkb ck dzg(y-24ercury initially descends a bit and then rises. Explain.

A glass container may break if one part of it) (swmkjur n4 2r1v:7l+yagmh is heated or cooled more rapidly than adjk 2:un(+ar lv4mr17jy)gsm hwacent parts. Explain.

The principal virtue of Pyrex glass is that its coefficient yutvpx-0a p:1 lu2eezl-tyfy 0f969i 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 :l-yay-p 2t1pue0 9yxvfz 9lei60ftuPyrex.

Will a grandfather clock, accuratml:b3e oys*cb. bf 4(,dqj7 xhe 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 and top to bulge so badly th9 f/ rit4:8avn,x3c igg*nkbr e can will not standr , r9i*gbv n8a43nfitk /cgx: up. What has happened?

When a gas is rapidly compre mv6;zag tr a.d2bmn,yuczq7) vz 923essed (say, by pushing down a piston), its temperature increases. When a gas expands against a piston, ayzv grb)63tnd,qmc e.u22;79zav zm 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 on an aluminum * 7xttjg+h ag:sphere submerged in water increase or decrease if the tempe*a:7jg+ txhtg rature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theory 6 rz qkb:xmj1ccohj2b261z )i and the relation between average kinetic energy and the absolute t 6bb)h z:i61cm2q 1z xc2rkjojemperature.

Explain in words how Gay-Lussac’s law follows from kineticmk d3 u.(rh-:x.mpmlhhwlw + 8 theory.

As you go higher in the Earth’s atmosphere, the rayl he(ts5 ih,zc r,dx): 2 7t z4oizmz:kg,n+xtio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed an object must ,5t6 g7lexxct5 u 4kqvlotc42ayhf08have 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 practically n x78futt54g 2,0 qol6vtc5klca ehx4yo atmosphere.

Alcohol evaporates more quickly than water at room temperature. What can yg tjaw:9/ xb8zp af.xar(j m0.ou infer about the molecular properties of one relative to the other?.m:ajpt a9 jg/ z0xxrwfa .b8(

Explain why a hot humid day is far more unco-t; i t-ez8;wgiechl 5qc0m 5n1: -muismhlz*mfortable than a hot dry day at the same temperature1eictzll hz t-*:ci55mm-u- si0n8m q h;;wge.

Is it possible to boil *gd +5jdu c 0mxllv76cjx30xowater at room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air tema rd8ks2,c+.rzci+* nzoogr6perature is the same but the humidity is different. Which is more densesr+ d6zg ocz*o8+, nrar.k ic2, the dry air or the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap of an overheated automobill:l/v1gz, cj :d26ktz9uu wuze enginec69t :2/wujugd zlzl zkvu1:,.

Why does exhaled air appear as a little white cloud in the wyzetxtps m- v)/he-s9p x 0zs5 n8.-jcinter (Fig. 13–28)?

  How many atoms are there inlt dtxtf65xnfft0 r/8jv3mo 1cl*h8 ) a 3.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare to theyjt3-f :z2b mn7hd qj* number in a silv3* qdft b-jmn :j7zy2her ring of the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. Whatrh3z:wkip5+9*u unzh( :bkx c is this on the Celsius scale?w9kh z:*3+:(5 uphiz kcnrubx   $^{\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 recorde0t44 jy8lbx kdd 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 columntyx(xqa; vp3* has length 11.82 cm at 0.0 qv py(*; xat3x$^{\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 bu5 gqrn ndfx040zlpmh4c2/b;x7vk sm5 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 je,h8kux5y* w:qqd 7t of wrought iron approximately 300 m tall. Estimate how much its height x7eq ju8 *:kdh w5y,qtchanges between July (average temperature of 25°C) and January (average temperature of 2 $^{\circ} $ C). Ignore the angles of the iron beams, and treat the tower as a vertical beam.    m

  To make a secure fit, rivets that are lmm4:v) v3vqy ifj/tixb. 4nl.arger than the rivet hole are often used and the rivet is cooled (usually in dry ice) before it is placed in the hole. A steel rivet 1.871 cm in diameter is to be placed in a hole 1.y:. li./m4xn mi) 3vtjqv b4fv869 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 watergtwud .ka (co o 79w)/0,indyr at 4 $^{\circ} $ C is $ 1\times10^{3 }kg/m^3$ What is water’s density at 94 $^{\circ} $ C?    kg/$m^3$

  A quartz sphere is 8.7q.9a4 naoil l(5 cm in diameter. What will be its change in volume if it is oql( aa.4n9l iheated 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 100.fvt opdw5 z,+*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 k-e inb.*jfc 8mL of water at 20 $^{\circ} $ C completely fills a container to the brim. When the container and the water are heated to 60 $^{\circ} $ C, 0.35 g of water is lost. (a) What is the coefficient of volume expansion of the container?    $ \times10^{-5 }$ /$C^0$(b) What is the most likely material of the container? The density of water at 60°C is 0.98324g/ml.

  (a) A brass plug is to be placed in (w5nkm)mpz t;ehjg , 2a 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, narrow vessel4c,l3 9goagu0r l1 cjcau uf6* so it can expand in essentially one direction only, show that the effective coefficient of linear expansion is approximaturl ,c1 3ouu6 lgja09cc fga4*ely equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the dens9 eo)s;grxv*nmvfit,e v 8u(2ity $\rho$ 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 coeffy hxto:,ge1.d;k ,wxaa-rz2e 7u6xx m icient of linear exerk1;:u,tx whxyxegm7 zo -x d,.62a apansion $\alpha$ 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 soqd j ;fvmwp5g t2f9*o lpv*;c1lid, $\beta$ = 3$\alpha$ if the amount of expansion is small. $\beta$ and $\alpha$ are the coefficients of volume and linear expansion, respectively. [Hint: Consider a cubical solid, and neglect very small quantities. See also Problem 18 and Fig. 13–30.]

  The pendulum in a grandfather clock is made of brass and keeps perfect time at :p *pf2c /ujxho rxqo,q3fp5017 : /rc o xjx,5puqh*fopq20 3fp$^{\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 ha-+0d jktha3 (zfoqz*;9yj yigs an inside diameter of 0.140 mm. The bulb has a volum*gyo(-0yz 3j f +kijz9 q;tahde 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 rotatwd)i6we fsz zkg*,x:w1 3ye 8ving about its axle on frwwke )*w8gy z,6fsdei zxv:31ictionless 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 requ ru) ppx,-1wmuired to keep it at this length if the temperature u-p p,r m)uw1xincreases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal ste9)yi-cob2wgr7r;z *xz 2q arsel I-beam of cross-sectional area 0.041$m^2$ is rigidly connected to two vertical steel girders. If the beam was installed when the temperature was 30$^{\circ} $ C, what stress is developed in the beam when the temperature drops to -30 $^{\circ} $ C (b) Is the ultimate strength of the steel exceeded? (c) What stress is developed if the beam is concrete and has a cross-sectional area of 0.13$m^2$ Will it fracture?

  A barrel of diameter 134.1vte4 w.rx+w5p22 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 Kelvit5 aa pzlnh hq7,rdh*( f;;2vin 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 temperfbt2lb/)2 o+ia p9w hmo3wyv4ature on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun are about 4ey9gt+t w bi cy98(n4g000$^{\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 tempvt;/9 hql, qcaerature of ab9thq/;a,cvlq out 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 ga)rta 0mm-8eohs law.    kg/$m^3$

  A storage tank contains 21.6 kg of nitroge. 1cyvpqv r5z7/.lz*lt ng 5ean ($N_2$) 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 1: v(..0 ygs4cuvkoxuq8.5 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 aqhux+f17:ohq d:7ok 7la-lkrc,xx 2it 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-Lgoo/ 7:kgx pf4 container holding 105.0 kg of argon gas at 385 :kogxo47 pg/fK?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg of ra.u6+ti/km-+qv to ,vzx zh4 $O_2$ 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 vrdvxhlj*:k-qn9 y:t vg z9 +;inside the balloon, which makes it less dense than the air ouvj9: vk- ltqnrxh;*d9gv+y :z tside. 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 zwk4qdzhs8y) : ne 0f;gsp/,c fw2yq(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 a6gx+rd7h3; bp jc yof(t 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 at sea level and+17 e,jdwedab/l rz3f 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 xtr /rr xj t.36bfhk(1/ $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water a2ug3 h5:dnp 3 h;ynh+qqbepc5re there in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) moles, yq 1lx6vr7uw 6wv3m ovl1,im,w1:hgn    $ \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 5.12* )pb hgct3dx$ \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 c7j*t eu )akgq4s z*x17*g vbdyou inhale that were also in the last breath Galileo took. [Hint: Assume the atmosphere is about 10 km t7es7dgxu1ag 4bvzk*jq* c*) high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of an oxygen moleculp, wfnq, c8nv 5/uz 7tmwul)n+e at STP?,vu qw/+87clp zn wm n)funt,5    $ \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 atomp3ksgos;oqu* iby e xgjt1+:50s* to/s near the surface of the Sun at a temperatu*j+yu0g s* o:ossitbx3g/t;o1pqe 5k re of about 6000 K.    m/s

  By what factor will the(mncmu d9y ly n yy6*m/,1nw,p rms speed of gas molecules increase if the temperature is incrydnly,1n96mpmm,n *cuwy(y/ eased from 0 $^{\circ} $ C to 100 $^{\circ} $ C?   

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

  Twelve molecules have the follo3t;20 rqshgfswing speeds, given in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, f g2r qshst03;7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in yq.ij/tctsh02 i*gj4a 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 it++cf zfabfd,ng :g3o:s volume is held constant, by what f, b n:fcf+3afgo+:zdgactor does $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is a5s , x bale45(ipmo:xgiven 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 sin11lqzh p;)v6pxmt , yk2i n;ame temperature, the ratio of their rms speeds is equal to thi; lvmnthi;,n)pq 1y p216 zkxe inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen molecules jjn;-z- ylpxa3 1-kdtcontained in an 8.5$-m^3$ volume at 2.1 atm if the total amount of nitrogen is 1300 mol?    m/s

  Calculate (a) the rms speed of an oxygej prckt889on mw-c-u2 n 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 mo t 2qh 7qmqva)k;i d8m ff+/,pkwu)0wclecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whosq*z0::wsdm+-s unfr me molecular mass is 89 u in a living celrnq0w-u:mz:d *f+mss l at 37 $^{\circ} $ C.    m/s
(b) What would be the rms speed of a protein of molecular mass 50,000 u at 37 $^{\circ} $ C?    m/s

Show that the pressure P of a gas can be wjt1rob,0,k zuf+mnwglvxl3. 2kyuc ;i j /./n ritten 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, *z tvhehozx:v3/cp/)jrl0w ) $^{235}$U and $^{238}$U (the superscripts refer to their atomic mass), can be separated by a gas-diffusion process by combining them with fluorine to make the gaseous compound UF$_6$ Calculate the ratio of the rms speeds of these molecules for the two isotopes, at constant T.   

(a) At atmospheric pressure, in b.7yh c w7is4uwhat 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 is 0.01 atm and the temperatur* 2wxvl u(2lgoe is (a) * lvolu2wg(x2 90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the hua+)sacd5b -p bmidity is 50% on a day when the temperatbbd5 cp-sa+a) ure is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water t6flg3/o. mqmfc 7 q;yboils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particul9lb4dcdm.i(n /sp f i8ar place in the mountains is 0.72 atm, estimate the temperature at which mpdb.ln(s94fi i 8/cdwater boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressu)t jlw6s qno8;kj+m *mre of water is 530 Pa and tk8m*jn)ml s+ tq;owj6he relative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial *i-j1t+3uy5sw cgj c5 gg6xvv pressure 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 pres ft 8urc)vh.zhw 2*w-80okbqfsure cooker if the water is boiling at a temperatuwh0* f)88 rzuv tk.wch -bofq2re 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 volrj6;-*kjp i xfc2g0 cmume 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 5p m( 9g;:6ffx :w3 o)sej:txpdsxe b+f $^{\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 (sg5 6ec0p5ue 2v pc)3q 4cpkndhee Table 13–4) to diffuse a distance of 15 g64 n 52 3)cpqvp5 cecdpkue0h$\mu m$ 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 takjpt 3w61e9v8+e5unqc )ph4l jl)mf o the interior through tiny tubes called tracheae. Awtjlpujfc4a+5n 9e8)kmep q6l1 h3v )n 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 measure has bee* wyc u4-olnac6nr3g s+1 pgk3n 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 meap1c3h; u qtbf;evs +yksu8.7ysure 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 s yr;51 4icnj*(tlcqccalibrated at normal room temperature. How much error will b;rc5c1ystcnqj4*il ( e made in a recipe calling 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 avv41/dk2t2k*ra ylyebi32q/ pdr ;zx helium gas cylinder is initially 28 atm. After many balloons have been blown up, the gauge pressure has decreas/ d*k rki pl2r4deby/v2;3zyq12va txed 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 3yg 7j ys sqa2 85puir87ce9bc-.1 m, anda-2bc 8j8yyi9 5sqge r7c7ps u 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 den6es8,dw* pv0se3 e v,urjauuff25 5oz sity of matter 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 attaina( x:zle0 gir(:ll((2r ttnmdjble using the best available vacuum techniques is abou2zilte:n :rmdr g0( (ll(t(xjt $10^{-12} N/m^2$ 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 lcx+wo u:g/(kumlv * ;dz5:xfa ungs to full capacity of 5.5 L when 10 m below the surface, to what volume would his lungs expand if he quickly rose to the surf*d:a+z ; gk(o:x fxluc 5wu/vmace? Is this advisable?    L

  A space vehicle returning from the Moonm xe b1.yudpom(-mn 1 0h ue(of6vpq74 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; indeed, part of it does vaporize, and this is seen as a bright blaze upon reenpo m6v dq7u(nu0x(f-4.1me bmop h1eytry.)    K

  The temperature of an ideal wz /pr/c)m ht8gas 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 volumebs,se . y- 720f jssdn(mywa2ah/8jxo 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 atmosphericrzjn l,- j6c;n pressure at the surface of the Earth, estimate the total number of ajnr, n6-lc; jzir molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contained in b/w yerk ).kxs3i;;:r wtva4ya 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 h) cu63unke3cqps:0wp/u-c gj6 f )phbas gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the upj )chbg:e0s6/nkwcu3c)u6 pfqp3- 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 l lw6jpi/1ph u4 /ynub2-ui7geiquid 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 gasolg .il2i(h v.f.c*au8;mbcbyv ine at 0$^{\circ} $C is 0.68$ \times10^{3 }kg/m^3$ What is the density on a hot day, when the temperature is 38$^{\circ} $C?    kg/$m^3$
What is the percentage change?    %

  If a steel band were to fit snugly around the Earth’s eqpmvrm: 0; /rlvssi7p 9(e/nrv uator at 25$^{\circ} $C, but then was heated to 45$^{\circ} $C, how high above the Earth would the band be (assume equal everywhere)?    m

  A brass lid screws tightly onto a glass jar*2lkn h*e unl4 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 thnbtvv+y5tw2 h :kk3 jd yqg:l)hg; 98se 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 pressur/bstzlcxt+6l:3n4 vh e 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 ikqbm3zi04p4 yphkzh0:1 mg n/s $ 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 against gravity by tennis balls thrown v2hu2 vho 2yz:rertically upward at it. How many tennis balls per second must rebound from the lid elvuh22 hyz 2:roastically, assuming they have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-vemjff v7(.8/dlkijf8 oc* v4cm-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 tmjv ff* j./4l8ek7ov(ivd 8cfhe surface?    cm

  Calculate the total water vapor pressure in the air j : :zrzh1bylu)k 5s;pon the following two days: :rh1p;5zjzysu)k: l b
(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 in;x (9 ;cwotsdj cr(n*ron at STP, and when it is a solid d*s cjn(o rdt;c9wn ;x(eep in 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 show that, for an idegjez(pz9, tq/ al gas at constant pressure, the coefficient of volume ex9,zt jp/ge( qzpansion is equal to $\beta$ = 1/T where T is the temperature in kelvins. Compare to Table 13–1 for gases at T = 293K (b) Show that the bulk modulus (Section 9–5) for an ideal gas held at constant temperature is B = P where P is the pressure.

  In humid climates, people constantly dehumidify their cellars to prevent romwmo-ag s s.ncy:qi:8c1t.a-t and m8 ms ny-1wcoa:qt . ca-gis:.mildew. If 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