Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the per2**tk+d0p6 v w* v2.znuqadun sl,xfziodic table or Appendiasznv *+u2w*fpxlk .nv0t,z duq26*d x B.

Name several properties of materials that could be exploit)p tw hgpc/j40cgv(;; v;imrgay; g; zed to make a thermometer(tg;;vvgahgpjci 4; 0/)ryz cmg;w;p.

Which is larger, 1 C ll 3 beomjo,1-$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, bxw vtk wjvx z7xcsjq:0-1w2/6ut B is not in thermal equilibrium with system C, what can you say about the temperatures of A, B, andxk1v2x j 6tw 7/zsxqjv:0- cww C?

A flat bimetallic strip consists -f +z tzdx7ci/of aluminum riveted to a strip of iron. When heated, the strip will bend. Which metal will be on the outside of the curd cti/ f+xzz-7ve? [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 lik:ie* 96;ut3 ocyplsae./p zynear 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 furnace (o7x3cs )5c2gnzrh3e e* phzvn6r 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 toec3nn)5*prsv2xeh zhzg367 c 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 endsd ezqe5 h n0,:w8,3hryu 6bmq8+g6irwsa ns/g often have a section in the shape of a U. ee shn3q6ysr8/80wur g,bi,+ ma6hzg:n 5wqd Why?

A flat, uniform cylinder of lead floats in mercury at 0 sdx wo isg(3,,$^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-,asz br45hq lm 66(, l/mtxewcglass thermometer is first placed in a hot tub of water, the mercury initially descends a bit and ax6 cwl,,zsq4 e bm 6/r(lmh5tthen rises. Explain.

A glass container may break if one part of it is heated or cog 9gx6; .lj66tjojk skoled more rapidly than;6k s6jk o9l6g.tgjjx adjacent parts. Explain.

The principal virtue of Pyrex glass is that it b9;pov1klj40vnz(4 5siszrws coefficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased 9i4 ksv0(zp;s 1wz54v jnbrl oheat resistance of Pyrex.

Will a grandfather clock, acvfs gf(f3f h 6a5, n:wojsp,i7curate 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 oxoji o 27w/;n ug0y:cg /;elwso badly the can will not stand up. What has happened?0g/ n/ wl x2;o;wegui:cjy7o o

When a gas is rapidly compressed (say, byx9be y7*mwrt +cl v v-,fr9-c pzk)b6g pushing down a piston), its temperature increases. When a gas expands a*-b)xezmyg kt b rp9r6vcc-fwv9,7 + lgainst a piston, it cools. Explain these changes in temperature using the kinetic theory, in particular noting what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force o8k.d57 nnjws cn an aluminum sphere submerged in water increase or decrease if the temperature is 5djw.nsc n78kincreased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles( bqctmr++j1i’s law follows from kinetic theory and the relation between average kinetic energyj(t1r+c+m i qb and the absolute temperature.

Explain in words how omq0n7o8bd8ok + (fkkb 2) spaGay-Lussac’s law follows from kinetic theory.

As you go higher in c *a vnhm.,5oierre/7the Earth’s atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Eartp*ier9k:by ;uh refers to the minimum speed an object must have to leave the Earth and never return. The escape velocity fory;*i pbr9eku: 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 no atmosphere.

Alcohol evaporates more quickly than water at room temperature. Wh d+j w0ub4v:9slyb2t /f.egmjat can you infer about the molecular properties9tu 0d bb:2+.l /g4mfvey sjjw of one relative to the other?

Explain why a hot humid day is far more uncomfortm0oqo4sg8rcjzn pj:) 53 n+zeable than a hot dry day at the s+3z j zo g cer5m)jq8op:04nnsame temperature.

Is it possible to boil water at roomc-rdy5h)/ va4 unig. h temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the humidity is diffe4 x8cu(f*l9wghflpl/ rent. Which is more dense, the hfl4w8gpcx *(l/uf l9dry air or the humid air at the same T? Explain.

Explain why it is dangeroustkepp z/(gi.jw ord1i0pk5(: to open the radiator cap of an overheated automobile engip0j1 wgi((/p:pk 5kertd iz .one.

Why does exhaled air a+g c*n ii-ys-pppear as a little white cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram rc1d .pj1.otm gu0p f3c-sag )copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold rk/b 7vjn)n xmijsr,84d* iky0ing compare to the number in a silver ring of t8rbsi,nd /mxv i0) jj kk74yn*he same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is oifyncva/c*j.gz + 0/aften taken to be 68°F. What is this on the Celsius scale?a/ca0n*fc+j yg i/vz.    $^{\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 recorf2j8;qov9 sbam ucw-* ded 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 therk:fjw0.wbtb ( mometer, the alcohol column has length 11.82 cm at 0.0 f:wwb(.bj k0t $^{\circ} $ C and length 22.85 cm at 100.0 $^{\circ} $ C. What is the temperature if the column has length
(a) 16.70 cm,    $^{\circ} $ C
(b) 20.50 cm?    $^{\circ} $ C

  A concrete highway is built of slabs 12 m long (20f7/p2p.dt;wiyuk bkm:rb2 u9s-t2x x . yk e8q $^{\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 (Fie t0x- m6oyga4g. 13–29) is built of wrought iron approximately 300 m tall. Estimate how much its height changes between o ay-x4 t0em6gJuly (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, riveubj2m q u,w-i2ts that are larger than the rivet hole are often used and the rivet is cooled (usually in dry icebwq-,u22mjui ) before it is placed in the hole. A steel rivet 1.871 cm in diameter is to be placed in a hole 1.869 cm in diameter at 20 $^{\circ} $ C. To what temperature must the rivet be cooled if it is to fit in the hole?    $^{\circ} $ C

  The density of water af 1us.vsi2fa9t 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 bek fixwqldg30b(1z. a- its change in volume if it is w3xli-0zb. dgf(1kaq heated from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with)le69kkkj(etv +f y*o 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 mL5;)c, fb u lkfiazi7j. 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 ,bhf+8x )6rily;ho v wbe 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, narrow vessel so it can 3*dpdi5s .;:sjsxdimxle t1 *expand in essentially one direction only, show that the effective coefficient of linear expansion is ad.s*sdse xplj3:i mx ti1;5d*pproximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the density cc/,*b/ub,: wj (wjv zfvu oc2yojj)2 $\rho$ 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 coeffic sjk (mtm8pboaibk k e8,*9l( ,3h;eeeient of linear exm; ke,iah3(*epes 9mo t j e8lkb(,8kbpansion $\alpha$ 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 solij,8 qr;dfj*:wpc5 o pwd, $\beta$ = 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 cloni rf6nm(fb/ /ck is made of brass and keeps perfect time at 17 i6(f/b /frnnm $^{\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 buyn385 he eo1an inside diameter of 0.140 mm. The bulb has a volume of 0eob 81hu3n 5ye.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 rotwzj* )p9ibaz *ating about its axle on frictionless9 zpajb)zw** i 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 desire0ohw0w npw+ ,bd length when at 15°C. How much stress is required to keep it at this length if the temphow bwn,0wp 0+erature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-sect(ujybuf)-qs(6. g3k 2 udhnppional 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 134.12,p f-fpm+ f, rf8h*xqo0ya(ec2 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 uvxi ,jt hsq(4rq i).zs 2zx)-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 the Fahrenheit scalw.cqyb+ i85 z .bdaw(z3ypy3w e?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun g kcu6g6/ikotv+ rz ,.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 nq ip53it+rp ,at atmospheric pressure and a temperature of abiq,rpt ni+p53 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 STP3e o/dl0 grsuha7s r.( using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of nitrowkab36 sbt9vg)+-eod( scc9 lok2,s agen ($N_2$) 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 containfag4v0. hrq.hbt2y o0,s j)tzs 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 heliumkl mabd(-l3vp(d6 ed ;yy c)y6 gas is 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 3gw,j/ /s/ zm b7l6 wwln85veuaizx p:holding 105.0 kg of argon gas at 385 K7nwpixv, g3luebzzsm///wj l:8a56w?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg o rr/9c 5x3pmz5 a/afv5ud:ei 6wxk2eef $O_2$ 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.jyscp 49synx *enfr7+ iq2(g heating the air inside the balloon, which makes it less dense than the air outside. Suppose the volume of a balloon is 1800g29 (r+ 7ji *yxqnycfpnse.s 4 $m^3$ and the required lift is 2700 N (rough estimate of the weight of the equipment and passenger). Calculate the temperature of the air inside the balloon which will produce the required lift. Assume that the outside air temperature is 0 $^{\circ} $ C and that air is an ideal gas under these conditions. What factors limit the maximum altitude attainable by this method for a given load? (Neglect variables like wind.) $\approx$    $^{\circ} $ C(Round to the nearest integer)

  A tire is filled with air at 15 j98ou5kk a*x. rj8hka$^{\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:aua 9pg4fm g;m9rli9.0 $^{\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 leveppkh c+/mgvdy u 3ex,82tlk6o1v *d( cl 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 molecule4xe3vmsqfqc + +rr- /ts / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water a 7+kjx ooxf+)ycg pbe1u)r 1(*og8bg lre there in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) moles, 9sbo yw6utisj41 7/.o: yujxi   $ \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(m- e x5ft6mmm.w bub8.1$ \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 of5bhfk2u v 0ge ftm.n;7 air are in each 2.0-L breath you inhale that were also in5ugvf mb ef7;02h.t nk the last 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 of an oxygen molec27v(n9r+luu u,mg.hmc ; gjj6kd v-t *yhek;oule at STl;6onhy h7m v.( k;gj-du 2e*+,cjmr utvk9ugP?    $ \times10^{-21 }$ J
(b) What is the total translational kinetic energy of 2.0 mol of $O_2$ molecules at 20 $^{\circ} $ C?   $ \times10^{3 }$ J

  Calculate the rms speed of helium atoms near the surface of th,t -a : xqu f svbycxyim.ul.,2wx5b50e Sun at a temperature of about 6000 K.ylw v-0,uu2q. xtm: 5bbcais y,x.5xf    m/s

  By what factor will the rms spdzjy b,q;h35 need of gas molecules increase if the temperature is increashyq3z;d n 5j,bed 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 follo48;*fusytror b5 0 o8aec fvlrkr.9s *wing speeds, given in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, o l*;4y f s*80vo .utb5k9ersa frr8rc7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of mol(ew:)tsz n/zsl/ o9d faoj,h 2ecules 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 itsknl4br n oj-;)w:xi5ez *yhh w03+owv volume is held constant, by what factor does j) :nwn ko+rlvxeizhw y 345hb;w -0*o$v_{rms}$ change?   

Show that the rms speed of molecules in a gas*jn kg4 aggl06 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 two,)nrh0 s3*1r jqkbodx gases at the same temperature, the ratio of theirrq 0nxrb1d j,osk*3)h rms speeds is equal to the inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen moljjuru-z:8 n :secules 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 rmtyzil7-i; 74rd;0cugek dm a9s speed 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 betwe0p6s: dz3ehnbr:giag c -.-zxen nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whf o vd:lzzu637ose molecular mass is 89 u in a living3lvf:ou 6zz7d cell 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 gasx.)00ony5dremkm v o3 can be written P = $\frac(1)(3)\rho v^2$ where $\rho$ is the density of the gas and v is the rms speed of the molecules.

  The two isotopes of ur lffcb to:r8-hxf,.)j anium, $^{235}$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 what phg -v74 i -+aqvzf+or,cd coxc5ases 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 0.01orco*k b/i(k;ble:r 6 atm and the temperature is (a) 90lrbko/c e:kro6*;i b( $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity is 50 *9mtdql; x)3s dxd3gr;pl ; o.fhfjp5% on a day when the temperat xqglddl3h3;.srx;m9p5pf ft );jdo*ure is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a plab 2xkgwz6 :0lmc 2k+mvce where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in pv*6 g(z;dajgcby0 e qv7q4)b the mountains is 0.72 atm, estimate the temperat6q*d c p7y0vb;egvjg) q(zb4aure at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partiazqlqx3w2 u0eynrz5 1y5 c; ;jrl pressure of water is 530 Pa an ux0nze j;rl5yrqq351yw2 ;cz d the relative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a if j5sco0(om , 8 +xnyvpfkrn)e97rl3o*6lzh day when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside z)) mk8be--gnqnd 6k na pressure cooker if the water is boiling at a tempb)e q zdnkm-)6n n8kg-erature of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a xq5pfi 6yb;q wl-kh/ci j/z7 qt--t*mroom of volume 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 poi77kqyqil i45hnt of 5 $^{\circ} $ C is drawn into a building where it is heated to 25. What will be the relative humidity at this temperature? Assume constant pressure of 1.0 atm. Take into account the expansion of the air.    %

  Estimate the time needed for a glycine molecule (see Table 13–4) to diffuse a dix3 vs4x gz:l w6mz)j)wsta6z :xsw) vgz4j3)lwmxnce 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 through tiny tubesy8xvv9 :ez+sf called+eyvfsv8 9xz : 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 measure has been calibrated at - nx8v vwqji;r.p .bqtaosadc2jpvs8 + + .55p20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A precise steel tape measure has been calibrated6gs12v2 d ciarz-ndcr- g gc.7 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 calibrated at normal room teiyei9 -m/p:ihaohxs ;v,u xu.zd.c+ (mperature. How much error will be made in a recipe call z,9hx :ypd xesi(.mhu+;cuiiv o.-/a 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 he bu :x(ml.dt,blium gas cylinder is initially 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. Wha, lt.:u(dbmxbt fraction of the original gas remains in the cylinder?   

  Estimate the number of air molecules in a room of length 6.5 m, widthkbus, 7e pl 45eb9z7pq 3.1 m, and s,kl9z 57 beubp7 4qpeheight 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 is aboutcaasyw5*2 x el)k 2mulh. (s7a 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 best available vacuum techniques is zxm:c *5dy ;blg*x0ohu,qa26fb(s cbabou6cby *mc0alhbud g qf;xo, 2*5z(x sb:t $10^{-12} N/m^2$ At such a pressure, how many molecules are there per $cm^3$ at 0$^{\circ} $C?    $\frac{molecules}{cm^3}$

  If a scuba diver fills his lungs to full capacity of 5.5 L wheszq 2lf pqb f:y4+ge/2,inc+xn 10 m below the surface, to what volume would his lungs expand if he quickly rose to 4zfq+b f,+:lsyei2 2cxgpnq/ the surface? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmosphere at a speed ofkd.3flw- ) vtueb byq*9s,c8 s about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with .bv u q*lyse)93wc-t,kdbf 8 sthis 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 reentry.)    K

  The temperature of an ideal gas is increased from mtb31ev lv- f-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 volume pn7h (2n gd7 +r)usixtof 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 kk3 n6jr 0l*vjnax z8;ji cz72u5:nzyof the Earth, estimate the total number of air molecules in the Earth’s kic:r 8xj3jjlz67 2an 0n*nkyuv5zz ;atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contaz 3tz+ pxtp9n:ined 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 pres1 wq4*vtdy)pekos m fx89w1. gsure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder lao fp kem)g4q.1xwvsd9t 81* ywst 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 liquis exo0g7) -pvxd 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 09 r kroi6,t:bkg*4df c$^{\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 arodny b 0o5y+o0k be3w/xund the Earth’s equator at 25$^{\circ} $C, but then was heated to 45$^{\circ} $C, how high above the Earth would the band be (assume equal everywhere)?    m

  A brass lid screws tighk;. vu/ 6k+emg w5xv7bgqon- dtly onto 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 703w;h yzrf,om2 1;ax bwbkopin the 18$^{th}$ century, was a platinum bar with two very fine marks separated by what was defined to be exactly 1 m. If this standard bar was to be accurate to within $\pm1.0 \mu m$ how carefully would the trustees have needed to control the temperature? The coefficient of linear expansion for platinum is $ 9\times10^{ -6}C/^{-1}$. $\pm$ =    C$^{\circ} $

  A scuba tank, when fully charged, has a pressure of 195 aty;te ;p)1 utcnm 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 fromu )hb 9tjg(p0e the Earth 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 against gravity by tennis balls thrown vebk6 h8sr:;pfr x7wx b2rticall8r6xhfkx 27w rbbs;: py 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 a 3.00-cm-diameter (spherical)3hucr1(tig +x /fh b7k bubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant atk(ci ghx r 1b+utf/h37 298 K, and the air behaves as a perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure in the air on the following two days/i(/upxcn)yx hl 6s;t: (;pui/xt 6y)n/ lxs hc
(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 bzb3 q-7stxw ;in the density of iron at STP, and when it is a solid deep in the t3 wbz-x;qbs7Earth 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 aad7x qz-u+:2rclu+:xya * yean ideal gas at constant pressure, the coefficient of volume+ ay7z ayuexa:q* u2:+cdxr-l expansion is equal to $\beta$ = 1/T where T is the temperature in kelvins. Compare to Table 13–1 for gases at T = 293K (b) Show that the bulk modulus (Section 9–5) for an ideal gas held at constant temperature is B = P where P is the pressure.

  In humid climates, people constantly de6958yvwkdiyk humidify their cellars to prevent rot and mildew. If the cellar in a hod69 y8kk5 yviwuse (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