Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodi 0gjlxu.:3r g*bfl5rdy ug/r( ogf.jom7 c93mc table or Appendix gl j9d0flg b.or3.xrj7 :fom(um3yc*g5 r/g uB.

Name several properties of material jty01pb/eom) s that could be exploited to make a thermometer./mb0jpy1e) o t

Which is larger, 1 C,//:c3uujc 6 j4l b so9gzc--oussxjk $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B is not i)j5g3ft* )c :xccymi:bwh 0 jgo27dt zn thermal equilibrium with system C, what can cjm:gg yc:)*7ot)2jdb0f iw53x ztch you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted(nm xsyeq 1fo:08;mxwx w/m o7 to a strip of iron. When heated, the st x70qxo8wn(/ e fsom:1xm;ymw rip 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 linea8 m4 n(3sh+0rqq uljvbr 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 thermostatqg-il1hkujl- a i 2- f)qm.gf( 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 cont- ljq2iak)gm1l-ui.hq(fgf -aining 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 fixed at the ends often have a section in the shape ow 7 68.ibs/ku+9v sod-lyomr uf a U.suvo 9l. yskbiudm-/ow8+67r Why?

A flat, uniform cylinder of lead floats in mercuzt 2gm0 m m+tvdt e0crt*cx)(*ry at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometer is first placed i)+w r xn;m*aw 7dlip0en a hot tub of water, the mercury initially descends aaeww)0imd xl* ;p+ 7rn bit and then rises. Explain.

A glass container may break if one part of it is heated or cooled more rapidly* mf3q+cc3xui than adjacefm3 xucq+3ci* nt parts. Explain.

The principal virtue of Pyrex glass is that its-fhwc1** etn p coefficient of linear expansion is much smaller than that for nhpf1* -wt e*cordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurate aelvv c(g .y.c;rjr(6vk0 *gent 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 sol4 ahcw(v. hl-j98p0kt4 xnzuda will cause its bottom and top to bulge so badly the can will not stand up. What has happened?zwxnll ht44a juk0 -c(89.pvh

When a gas is rapidly compressed (say, by pushing down a piston), its tempemxf ke j4bk*c gmy.m5oci-:l83 *wf:drature increas.f3ke5im*mx y:wm*cb-:c o 4dfkl8 j ges. When a gas expands against a piston, it cools. Explain these changes in temperature using the kinetic theory, in particular noting what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force on an aluminum sphere submerged in water increaj 9cihbeck*,bb f9(/nse or decrease if the temperature is increased fe b kfhc/b(,9cbjni9*rom 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theory and the95 5vlkzx g lrr;v5m9+iza 7gq relation between averagexl gvgi zm 7rlqvk95+55 ;arz9 kinetic energy and the absolute temperature.

Explain in words how Gay-Lussac’s law follows from kinetic theorreqzo55a k2r1 rdn4+ yy.

As you go higher in the Earth’s atmos61,a qfqim(om1yox:/)lsjti g 4 ton7phere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to t, soo09tuvc-p he minimum speed an object must have to leave the Earthco p9t0v, s-ou 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 no atmosphere.

Alcohol evaporates more quickly than water at room temperature. What can yohn.q8xyom,-n u infer about the.- q x,ynoh8nm molecular properties of one relative to the other?

Explain why a hot humid day is far more uncomfortable than a hot dry day at tf0a/j8i(ayt *ddd 9.enac hl.ebq*l :he same tedfd/l :q8a0l*ad nyhe9e. t.ba*j ( cimperature.

Is it possible to boil wadjw6obmb nl4 (/qnx .7ter at room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but th;,3a jum qk;qne humidity is different. Which is more dense, the dry air orqmjau3k ;;,qn the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap of an overheated a/pd9 e iemw/k8utomobile e 9 idwm8//kpeengine.

Why does exhaled air appear as a little whit 9r ur9 fjhot+b hyyv3 wa8i6)ni4 -f(8vriij9e cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram c s9fj1nw ;3tjnopper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of ah;a/-j /pm2lf8yb/96yovg ygp,yy ni toms in a 26.5-gram gold ring compare to the number in a silver/8a/l /- yg ymyb gy6,vn;yi 2fhpj9op ring of the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. Whwnq7+b4 m 97akd9f rtiat is this on the Celsius scale? a7r dtqinf9wmk b947+   $^{\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 91a,8 e-+njs1ey t bagymhnvzyt+sp+0- h8nhtemperatures recorded are 136 $^{\circ} $F in the Libyan desert and -129 $^{\circ} $F in Antarctica. What are these temperatures on the Celsius scale?high =    $^{\circ} $ C
low =    $^{\circ} $ C

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

  In an alcohol-in-glass thermometer, the alcohol column has length 11.zicpxu8+k ,hgwe j8b1 e*m*m0 82 cm at 0.0 eu+e*xz wm0 j cg*k8,8pim1hb$^{\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 lonb 7:zr keqo;k*0lybm 1g (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 bui s/s*a7awhofq r-0u w5lt of wrought iron approximately 300 m tall. Estimate how much its height changes between July (average temperature of 25°C) and J/usah f*aswo 7wrq50 -anuary (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 largeqb5f8: te /cazq 0c0asr 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 1a ezb:a ft 5s0q80qcc/.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 at ca-e:,hxf :9 riqnp++ zm5+r smenb 6v4 $^{\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 i+ tcw+ka y0jr4* npq2pn volume if it *wt0yq++rja2 kpn4cp is heated from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350.0 og(uhz e*gm+g0oux-- 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 mare6qq:v7dab / c7;5qfr2 s eoL 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 a rin:y xbsp,l/b 5yg n(0rng 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 expand ckz4 e3dql/ w75wdj 0gin essentially one direction only, show that the effective coefficient of linear expansion is approximately equal to the coefficient wdlz4jcd0 we5k7g/3 qof volume expansion $\beta$.

(a) Show that the change in the densijxs-a 353 nl ymukn2-aty $\rho$ 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 oqul1y 5lu q+wnb(x9 oyp ;7qp(f length l and width w has coefficient of linear expansioylqyp xqo(9l un; 5+u7bw(q1pn $\alpha$ 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 isot q9pz rij7*ppl+ -gf1xropic solid, $\beta$ = 3$\alpha$ if the amount of expansion is small. $\beta$ and $\alpha$ are the coefficients of volume and linear expansion, respectively. [Hint: Consider a cubical solid, and neglect very small quantities. See also Problem 18 and Fig. 13–30.]

  The pendulum in a grandfather clock is made of brass and keeps perfect ti vb/x y)):5xmp)vysw ame at 1aps))bx)/v m:xy yw v57 $^{\circ} $ C. How much time is gained or lost in a year if the clock is kept at 25 $^{\circ} $ C? (Assume the frequency dependence on length for a simple pendulum applies.)$\approx$    min(Round to the nearest integer)

  (a) The tube of a mercury thermometer has an inside diauhj sqwg/v(m9 jx/a ;,xx0*opmeter of 0.140 mm. The bulb has a volum0jx uwa,/ xqm*ohjv/gp sx9;( e 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 rotating a5 vxgp ;wa3r6n -6:nd:jckr knbout itsxk5kp cn 6nw-jnrv:3gr ; :a6d axle on frictionless 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 l9cpu*b ku z2i:ength when at 15°C. How much stress is required to keep it at this length if the temperau*2:zc i9 ukpbture increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-sectional area5 :m oaf.1a7 dww/dfqu 0.041$m^2$ is rigidly connected to two vertical steel girders. If the beam was installed when the temperature was 30$^{\circ} $ C, what stress is developed in the beam when the temperature drops to -30 $^{\circ} $ C (b) Is the ultimate strength of the steel exceeded? (c) What stress is developed if the beam is concrete and has a cross-sectional area of 0.13$m^2$ Will it fracture?

  A barrel of diameter 134.122 ch cd1- uno(z8t(i)t bmm 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 t*yvic:y)5 zi uhe 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 cl.wcw*b;,e:x2k*vgnj es0rscale?    $^{\circ} $ F

  Typical temperatures in the interior of ojxqp42/3(lmhmmc psc*h++c -r n9 pythe 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 combust q6cfs jz,/dwnjp+e2+81g cfx ion engine, air at atmospheric pressure and a temperature of about 2j8p,qecw fxf +djc12g+s 6z/n0$^{\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 gas la b)11lea n+nm r+n mh2iuz1qp3w.    kg/$m^3$

  A storage tank contains 21.6 kg of ndm kax+/eeby; 0zx pll6/-.m6fpj w-t itrogen ($N_2$) at an absolute pressure of 3.65 atm. What will the pressure be if the nitrogen is replaced by an equal mass of $CO_2$    atm

  A storage tank at STP contains 18.5 kg of nitro*1at a fpmwj 6kv,muq4(5g yu-gen ($N_2$)
(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 i r-hhhfq 82epg*34 s h.6sabays 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 h/y;wz0p14(xpc d77bocoqr tyolding 105.0 kg of argon gas at xy0b ozdc(r7 /qy41 powtc7p;385 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0e3.h-nwk,8hyqx- by 7g nbi-c eod9v( kg of $O_2$ gas at a gauge pressure of 8.70 atm. If the oxygen is replaced by helium, how many kilograms of the latter will be needed to produce a gauge pressure of 7.00 atm?    kg He

  A hot-air balloon achieves its buoyant lift by 3:-miv+uog ym., dcdj heating the air inside the balloon, which makes it less o+gyjm3id:.vduc m-, dense than the air outside. Suppose the volume of a balloon is 1800 $m^3$ and the required lift is 2700 N (rough estimate of the weight of the equipment and passenger). Calculate the temperature of the air inside the balloon which will produce the required lift. Assume that the outside air temperature is 0 $^{\circ} $ C and that air is an ideal gas under these conditions. What factors limit the maximum altitude attainable by this method for a given load? (Neglect variables like wind.) $\approx$    $^{\circ} $ C(Round to the nearest integer)

  A tire is filled with air 0cx; n ,vntc9s 4i06qpv*e hu-rsfi-g at 15 $^{\circ} $ C to a gauge pressure of 220 kPa. If the tire reaches a temperature of 38 $^{\circ} $ C, what fraction of the original air must be removed if the original pressure of 220 kPa is to be maintained?    %

  If 61.5 L of oxygen at 1 vkpqysj-2d);zujp 5;a;p jj.8.0 $^{\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 e:n:-hv+nrbikcs+ c* 2aw9fm exi z6-iscapes a child’s hand at 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 molecsj9 lqs:j,jq 7ules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 :h wdq;-m p13ig:2bruk b6xhm L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of ( (4 qtd:njpr(da) moles,    $ \times10^{22 }$ moles and (b) molecules of water in all the Earth’s oceans. Assume water covers 75% of the Earth to an average depth of 3 km. $\approx$    $ \times10^{46 }$ molecules

  A cubic box of volume 5qnhj8h gh*ebd89 1o* s.1$ \times10^{ -2}m^3$ is filled with air at atmospheric pressure at 20 $^{\circ} $ C. The box is closed and heated to 180 $^{\circ} $ C. What is the net force on each side of the box?    N

  Estimate how many molecules of air are in each 2.0-L breath you inhale that we(gnle4:s (,aie:tes1 xi xib5 re also in the last breath Galileo took. [Hint: Assume the atmosphere is about 10 km high and of constant,s1e:gti ae(bx5 l4ni(: ixse density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of ftn kioqxn , d*32;;svan oxygen molecule at STP?,3 d* t;xv 2nniqs;okf    $ \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 ata/ o/o 7t6b4pnpg)auz oms near the surface of the Sun at a temperature of about 6000 )otz6a bn/a7pu 4opg/ K.    m/s

  By what factor will the rms speegm9bmp n( cxmb6)39e w. /oywzd of gas molecules increase if the temperature is inc/z)6 em 9.mocm(y9bn wp3bwgxreased 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 following speeds, given in unkqj(n.(c /ew1;xfdzl plq.( sits of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calculate the .;dqq ((feklnc z/j l.p xsw(1rms speed. $v_{rms}$ =    km/s

  The rms speed of molbp-okgp6v ct:/9)cnse 99le tecules 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 xm fkvr6l(,r*volume is held constant, by what factor vmlxf( 6rr, k*does $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is given b g7++jcm1-;iju3eaw h0prrrj s jm8/ey $v_{rms}$ = $\sqrt{3P\\rho}$ where P is the pressure in the gas, and $\rho$ is the gas density.

Show that for a mixture ofb5lfgg*i emj n)(qb () two gases at the same temperature, the ratio of their rms speednil5e*(j mbggf) q ()bs is equal to the inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen c d(a dji)zuym10cp.( l,.*xfeqe :pomolecules 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 s lvn-+*dnmfxl0v 4 g7vpeed 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 molecules at STP37o :lzdsm odt:4f0sp ?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an,njujy0p;7 tp63p gaw amino acid whose molecular mass is 89 u in a living cell3p ,;agnj0utp6 7w yjp 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 written3 uf sdnn7ny2n9)c 4ow 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 w 2nwx tqp 3-kz0gn ele:(5g8*h:mlp suranium, $^{235}$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 phases ca d. d4b d:iw4dj+i6ikvn $CO_2$ 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 iq ixj+ok1 (d3m9wp) ors 0.01 atm and the temperature is (a) +wqmpi1 (o o9xkdj) r390 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (af7d1 krb4xp2 0iox45kzipo e7 pproximately) if the humidity is 50% on a day when the temperature is 25 z0pkrf2i7d1 oeb 44x o5 ixkp7$^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure ayka/kytl3xz1o 42fa4a u fj3u/t5. ixt a place where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is 0.72 atm, xa2(dtm3 *-cwb og /nvestimate the temperat/a-g b(*von2dxmw3 cture at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day7j8d:jj ,u+5 mbnrwlv6x v ,obactz* 8 when the partial pressure of water is 530 Pa and the relative hz,ou5v 6b cv+,br*wtj7a8 m:d nj8lxjumidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a dawt*b* ocgqbh68 jf7 3pl*ai )yy when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure insid*z3t f(8ospc ie a pressure cooker if the water is boiling at3(tos 8p iczf* 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 zy,6ipb7aj5uz 0z8g n, 1fgcivv yg36of 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 point of 5 gy 02kui 31w,a kn. ooi9jp85ysnf5ar$^{\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 dif 7-;3rvwewssi *ok0n lfuse a distance of 15 e o 37s0i*w-rnk;lwvs$\mu m$ 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 throug8djn) xbd9i;fo ovrv,16rpf4h tiny tubes called tracheae. An average trachea is about 2 mm lo6j9povvxb fr4o) d irdn, 1f8;ng 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 calibratedm6 n jp)dz(cf- at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A precise steel tape measure has been calibratexwc) .zjm m9.kd 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 calibrateintbc7c5ou(i6 roo yacw l7-g+r 9k(6d at normal room temperature. How much error will be made in a recipe calling for 300 mL of cool water, if the water and tk79wogaub oioic+cr -5(yrc6 n 6(7lthe cup are hot, at 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in a helium gas cylinder is initially 28 atm. After many bal) x2k nqju.y/uloons have been blown up, the ganu/q 2yu.k)j xuge pressure has decreased to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air molecules in a room of length 6.5 m,jd)g3i(5oy1 nw:pji c width 3.1 m, and height)pjwdic( 1 o:y5gj 3in 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 matter6 9 qeu0*jnpgc is about one atom per $cm^3$ mainly hydrogen atoms, and the temperature is about 2.7 K. Calculate the rms speed of these hydrogen atoms, and the pressure (in atmospheres).$v_{rms}$ =    m/s    $ \times10^{-22 }$ atm

  The lowest pressure attainable using the best available vacuum techniq2 9b +yzav8aywst w+x3( o.lm6mzk+jlues is abo+8m( akw l+y x9btysl3wz2az omj.v+6ut $10^{-12} N/m^2$ 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 lue+fdo9w,o /gwuayk4ur x3p,5 ngs 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 surface? Is this advisa,of+ 9yp 3o,uagxdu4k /rw 5ewble?    L

  A space vehicle returning from the Moon enters Earth’s/hui.sx 8w:ee atmosphere at a speed of about 40,000 km/h Molecules.e:w /xs8ueh i (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 reentry.)    K

  The temperature of an ideal gas is increa:4+hov2sea*p -z 4vrfb :sohvvdy5 : xsed 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 volume of 77dl b)-z4 tf a.xrof8ay(kp,p30m$^2$ (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 Eaa+)f-nygzzb fr5s 7f:rth, estimate the to :as z-yb7ffnr5)+ fzgtal number of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen mo4a3 vor wq0g1klecules 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 usey5,qodpo1q+ f d in a hospital has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow r+o5 qq o,ydfp1ate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liquid mercurqs6vt0 kn8 ;zgy 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 avlq7 x1g ;(tk h(x1l; g6isabpt 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 Ear( firfe7i:d) z lt;7dm64mx quth’s equator at 25$^{\circ} $C, but then was heated to 45$^{\circ} $C, how high above the Earth would the band be (assume equal everywhere)?    m

  A brass lid screws tightly onto a gl8zm9n5 lxjiiit x,;+43:wa gnql fgflu 3+l4kass 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 01/hyy5fg*lf 3mqhwfin 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*o5ec l8zir5x+v ,aam3 qxyp 2 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 Ea 1o/ys lh0cs7irth 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 isr z k++e6bu atw9gmt.;cmixpa,-24 ro suspended against gravity by tennis balls thrown vertically upward atxbk ma erzp 26w+;ricoutt 4-,.am9 +g 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) bubble of air fron-vp h-bgy 4 . buzh//ldd1:ulm 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 reacheshvpl/1ud4 -- ygdbhb.zun:l/ the surface?    cm

  Calculate the total water vapor pressure in the air on the following two days: zong: zge;9gasbb.6 ;;g.sa9g6 b nozbe;gz:
(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 g-ruw ,3upj vsw;sd,6is a solid deep in the Earth where the temperature isw uvr-gs,6jd,p ;s wu3 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 ide1 r 3+aoiwtap+r9kzk ye.,qu3al gas at constant pressure, the 31a+ye. kr3q i9+t,wrz uapkocoefficient 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 constantly dehumidify their cellars to pr6, qznlg20hgg; z/ppkevent rot and mildew. If the ce6/ g0nhgzgzk2;, ppqlllar 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