Which has more atoms: 1 kg os wh1br ksdb;-4zm: k2f iron or 1 kg of aluminum? See the periodic table or Appenw ; sms41:dbhkzkrb- 2dix B.

Name several properties of materials that could be explg5e xed0l gj b5pm;4x/oited to make a thermometere; 0l dexgm4pxbj/g 55.

Which is larger, 1 Cd)zf a0uujm/.+bgq s utx). m)brn+w2 $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B is not in 2 y nic(vovqq 6*e6xfpt+ 2/tjthermal equilibriqxtipv66qen* (t 2 +c/2joyvfum with system C, what can you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to a strip of iron. Whengmi.ff e-0dwuev c-yro)k1 -/ heated, the strip will bend. Which metal will be on the outside of the cureoe -vyfd f01)wik.g/um --c rve? [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 coefficienz hd;fp. 9r6zp/tk/dc f-svm7t of linear expansion $\alpha$ are $(C?)^{-1}$ and there is no mention of a length unit such as meters. Would the expansion coefficient change if we used feet or millimeters instead of meters? Explain.

Figure 13–27 shows a diaoa,49xux (rr98czboy gram of a simple thermostat used to control a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch is a guybr9 (xx9o4a z8oc,rlass 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 fixed at th(xqa-cmrzqv4 .5:l raqj+y. me ends often have a section in the shape oflaxr5yqq .(vm+4 r:zc-. aqjm a U. Why?

A flat, uniform cylinde uo/ci2hn8i k3r of lead floats in mercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometer is first placed in a hot2ffizb+i0gmfvlh j ws /ddl+.*. +i (n tub of water, the mercury initially descends a bi* gnf2id jw di.ml+z(f+./blf+0s ivht and then rises. Explain.

A glass container may break if one part of it is heatec 1wrzx+sg2d d44c-7-kezjejm+w9 wcd or cooled more rapidly than adjacent parts. Expjzxc e kc j+7w4m- swr1dw9+cd-e2z4glain.

The principal virtue of Pyrex glass is that its coefficient of linear.aid5)n euur01avy56pa 9 jj8aye.d d expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat dyd e v1y.j8dr5j6.a5nei0u)u9aa ap resistance of Pyrex.

Will a grandfather clock, accura42vqc.ksy.8u 7ri o ekh,rpq9te 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 thepsts wenk2,pbw. vc 2. x3d94i can will not stand up. What hab,.p2exnkvw s. 4i c2p dw3s9ts happened?

When a gas is rapidly coagb)0 d6iux+)wvw h +zmpressed (say, by pushing down a piston), its temperature increases. When a gas expands against a piston, 6 gwb+h)wi0+dx v)auzit 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 submerwap)q8gut +pld 1- k6jrs *l6qged in water increase or decrease if the temperature is wd+s q) r*k16lgpl8puq aj6t- increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theory and the ksk ,0cul:m3 wrelation between average kinetic energy and :k0l3 w,sc mkuthe absolute temperature.

Explain in words how Gay-Lussac’s law follows from kinetic theor9bxlaoi25 *9h fwx+ kiy.

As you go higher in the Earth’s atmosphere, the ratie)ld 2:r eu*(dfdk-ibo of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minu(unk 0k3)di1 (hvgm kimum speed an object must have to leave the Earth and never return. The escape velocity for the Moon is about one-fifth what it is for the Earth due to the Moon’s smaller uv 1(3dnkkhku(0 g m)imass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quicxn0t t7 wzfgz*cu:i/+kly than water at room temperature. What can you infer about the molecular properties of one relative to7w/uzzin: t cgxt+ *f0 the other?

Explain why a hot humid day is far more uncomfortable than a hotib5cxn*-ew+ky k j)j2 vf+gn mg8/( dl dry day at the sa8(yn*jd5nkx) /g l2jbv-+c+wfg mki e me temperature.

Is it possible to boil water at room temperature (20 2h- xu:8a5kn yc hl.tks4rc ak+inq7 7$^{\circ} $ C) without heating it? Explain.

Consider two days wh-oirpy 86itnm6g3+ k sen the air temperature is the same but the humidity is different. Whic+mit6nyo683irg-s k ph is more dense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerous to open the radiajwlyesp+.jzvze4. : 2tor cap of an overheated automobile enginezj: .v+z2epw.4ejl ys .

Why does exhaled air appear as a little white cloud in the winter (Fig. *y6 wd .as9jqr13–28)?

  How many atoms are there in0egi)itt77s *1kyp yl 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 t1 -ca-fivle9.mh bh: 6t0vzeo x0w xt(he number in a silver ring of the same mass? xit0-z9.w6xce vaohme-b 0 tvfh(: 1l$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be:;/ z) tlsmn /5pl uds.1vlmqe 68°F. What is this on the Celsius scale?1v)les:s;dnp l5/. l/u qzmmt   $^{\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 temperhhc(uaq;2, wj3 )zspoqmw: o9atures 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, nz9.z,jc5 xum the alcohol column has length 11.82 cm at 0.0 j 95xuz.m,czn $^{\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 (20 4edb)9 98 nfagwnw/)01bgnh6xm zci e$^{\circ} $ C). How wide should the expansion cracks between the slabs be (at 20 $^{\circ} $ C) to prevent buckling if the range of temperature is -30 $^{\circ} $ C to +50 $^{\circ} $ C?    m

  Super Inva$^{TM}$, an alloy of iron and nickel, is a strong material with a very low coefficient of linear expansion [0.2$ \times10^{ -6}$(C?)$^{-1}$]
A 2.0-m-long tabletop made of this alloy is used for sensitive laser measurements where extremely high tolerances are required. How much will this table expand along its length if the temperature increases 5.0 $^{\circ} $ C? Compare to tabletops made of steel.   $ \times10^{-6 }$ m    $ \times10^{-4 }$ m

  The Eiffel Tower (Fig. 13–29) is built of wrought iron approximat dy0xq8:a 2ve- v,pw27pmynk gely 300 m tall. Estimate how much its h-v2pan0w g 7p ,m2:dekx8 vqyyeight changes 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 la m*;fox bp-el3fnax 0fc84y .y/bksd0rger 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 t0pf;n8 yecxo.fxym/3 4sal b0kdbf-* o 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 q*l d4+mhoc.sams: *a 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 8.75 cm in diameter. What will b;wfzlkr)xj px7u+ mq 6 82b)pke its change in volume if it is heate 6)jwlpq f2z+u 8kr7kx;mx p)bd from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is fill zt;2 kqta +qj;))luko06b xwsed to the brim with 350.0 mL of water at 100.0$^{\circ} $ C. If the temperature decreased to 20.0 $^{\circ} $ C, how much water could be added to the glass?    mL

  It is observed that 55.50 mL of water at 20 wnc()nwav* z,3+trl/q ,vhy z$^{\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 ring made of iron. At 205gjhr-d lgz,6 ps 71ys $^{\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 in essenti)ed)m9wl2wh; ea.; mvgweqj7 ally one direction e g 97qme wwh.vd 2e;w;mlj)a)only, show that the effective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the den d57djx8;pzcub r1b7g sity $\rho$ of a substance, when the temperature changes by $\Delta$T is given by $\rho$ = -$\beta$$\rho$$\Delta$T
(b) What is the fractional change in density of a lead sphere whose temperature decreases from 25 $^{\circ} $ C to -40 $^{\circ} $ C？

A uniform rectangular plate of length l and width w has coefficient of linear 0*moki:0 ;db o0weavd ex0w :;v0bokam odei0 d*pansion $\alpha$ 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 pkp1zs g92s7ysolid, $\beta$ = 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 gr(fdaur .0x r,)npx3 fyh1g fm-andfather clock is made of brass and keeps perfect time at 17 u0fhmd1agp(-xx ,ry .f) r3nf$^{\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 pu:-in; u/yjg + dq9pzan inside diameter of 0.140 mm. The bulbj pdi 9qyu/;z:g n+u-p has a volume 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 cylindrid(v;qorbkf ,ipzv8g,59q 7 aecal wheel of radius 0.41 m is rotating about its axle on frictionless bearings with angulri evo57 z ;v(qqdfgb8,,9apkar 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 lengthxmo-6un6(j 4xo /nzp nw8yq8w when at 15°C. How much stress is required to keep it at this length if the temperature increases tz /6w-(8mw n4joxnoy6 xq8npuo 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-sect 2yhqz9ml ))hxional area 0.041$m^2$ is rigidly connected to two vertical steel girders. If the beam was installed when the temperature was 30$^{\circ} $ C, what stress is developed in the beam when the temperature drops to -30 $^{\circ} $ C (b) Is the ultimate strength of the steel exceeded? (c) What stress is developed if the beam is concrete and has a cross-sectional area of 0.13$m^2$ Will it fracture?

  A barrel of diameter 134.122 m9gr4 /o*+kz;hy lq2 tynr3 zkcm 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 Kelvin sca6dy:hyk *, jdfle:
(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 temperatux gko/.nun z-. t/5cim0x;ner66 vlajre on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun are aboj( 3kwjn :7ndlut 4000$^{\circ} $ C and $ \times10^{6 }$ $^{\circ} $ C respectively.
(a) What are these temperatures in kelvins?    K    $ \times10^{ 6}$K
(b) What percent error is made in each case if a person forgets to change $^{\circ} $ C to K? $\approx$    %(Round to the nearest integer) $\approx$    %(Round to three decimal places)

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

  In an internal combustion engine, air at atmospheric pressure aneo vd-)c,/7iumellc ,d a temperature of e7,- /ll)me iv,udc ocabout 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 gas law. iis 57v5i8z k u8c,and   kg/$m^3$

  A storage tank contains 21.6 kg of nitrog*ar0s3 aq5tjven ($N_2$) 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 omu)*,c1 aug ;/vtq pbtc7vv 6ff 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 heliuow ny*5;sx(vw7f8y9 vp qw csh/tc)s*m 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 holding 105.0 kg of argon gkn.w h ,np2v/(rt:olq 8mlg 3das at 385 K? 2o:ldg qhnw 3kp(.lrn,v m/t8   $ \times10^{ 8}$Pa

  A tank contains 26.0 k(.jthr2mc (z q7tg v0lg 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 heating th eq(lp 5 nws/*hb-cc)pgzz 82ze air inside the balloon, which makes it less dense than the air outside. Suppose the volume of a balloon islhpe-2 (p5)w8 ncz*c/zgzs qb 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 with59- x3jwsrkklz s 0sd4 air at 15 $^{\circ} $ C to a gauge pressure of 220 kPa. If the tire reaches a temperature of 38 $^{\circ} $ C, what fraction of the original air must be removed if the original pressure of 220 kPa is to be maintained?    %

  If 61.5 L of oxygen 7pgw+jayj /2wat 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 hangr(hi8z:a/ea ) rnn.v d 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 2w,jem*( h,upkfn z5 0*cfwt pof molecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How many )vr:rge15 mim(asux0y5 dr- p molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) mtmd9fhk4 6fr +h c3ry4oles,    $ \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 54 ft 3(aibbu9j.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 infc,8 9uan0f 7iy(llk0zt*s ;jak ( oufhale that were also in the last breath Galileo took. [Hint: Assume the atmosphere s*8yk fio(utl zf c0j7( 9kauna;f0l, is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic ener5lus e2 eg xv9wy4z py9.yc4:1 gd.flygy of an oxygen molecule at STP?4g dzy:euy2f w 4ex v9cy.sl.yg5pl19    $ \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,pw 9cnxb,ztz e)8-le near the surface of the Sun at a temperature of aboutbc9)ze,,nw p ze-tx 8l 6000 K.    m/s

  By what factor will the rms speed of gas molecules increase if the )ie dj /a,yutcqc ;9b(temperature is increased fromcj i;y)9 u,bc(t/ adqe 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*9u d-tkknt9- .p:d wimrx t1u in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calcu-udnrdk-*:t .ku wi91 9 ptxtmlate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at 20.08u)fqa*arr1obo wl)ef0nu - 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 )+g8( :wixygjn3gv tp its volume is held constant, by what fact+n vg3)j(8gyix p: gtwor does $v_{rms}$ change?   

Show that the rms spyeu8q0zi d+ 4 ;a3jygr+cti:(5 x cscgeed of molecules in a gas is given by $v_{rms}$ = $\sqrt{3P\\rho}$ where P is the pressure in the gas, and $\rho$ is the gas density.

Show that for a mixture of two gases at the same temperature, the ratio o8 )d.kn+jz sguf their rms speeds is equal to thej +) d8kgs.znu inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen molec.c :izzlzyye,4 l q(p+ules 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 speed of an ek 7-9k yay8e)qbtjn(+vk vd: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 distancqiq(++:1f b hjdw 7hswe between nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecup06re j r,*p :pq2 ayuj h0*zzi1vlvm(lar mass is 89 u in a living cell at 3ujz 0rmaq2y e1*,vh*:lj( pi0v6rpzp 7 $^{\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 gasa8lkw,4kfd 5 z 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 ur3tqs+f/6a w)cvt b79 /a;u xwcb/ himyanium, $^{235}$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 p+k7z ge1zyz) dsp1o h)3c zd0uressure, in what phases can $CO_2$ exist? (b) For what range of pressures and temperatures can $CO_2$ be a liquid? Refer to Fig. 13–21.

Water is in which phase when tqf )d 1 (f,cbfbt3x6qehe pressure is 0.01 atm and the temperature is (a) 9f) fq( ef3bx q6,cd1tb0 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity is 50% on a day wqu)c(ghe .mi 3hen the t3qeiu(c )hmg. emperature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place + k:zmusjh,f0 where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is 0.72 at )z1m4eediw7j9 l iv74xawm d77tqz 4xm, estimate the tempdzz l9x44m4e7 id7)a 7q7w ewivxt 1mjerature at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day wh, feqy(8q/pbh ,yj /nzen the partial pressure of water is 530 Pa and the (h e,yn, /8jqfqyb /zprelative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of bk q41b e,qj)g:pvsh/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 pressure coo k:tdprq+7 2pav4o0bbker if the water is boiling at a tempq0 abd:p2v7r ptob4+kerature 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 vob2l6eo ( if+ablume 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 of6k9c6c4 jvr r ak0wdf* 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 (se futq pc0af2*wtc- qgq/1zv-7e Table 13–4) to diffuse a distance of 1-*faz tf0t7vpqgc-wu 2 1qc/q5 $\mu m$ 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 tubes cfh w6xe7u:emphyv3yu 4kyk i3 8-.*wqalled tracheae. An average trachea w h*ue3yy 7-:f6xykpu i.kwheqm348 vis 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 calibr ,w8s. gfoblf 83nv;khated 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 c- ge5gjc.:ryr alibrated 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 tempera/62sh,6 jngnyg,trs pqy b:: dture. How much error will be made in a recipe calling for 300 mL of cool water, if thegs,b 26 :6/ys nnthq:pdjgy,r 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 heliumq1 u7bczm+enu cp ,ddnq1/ ;3c gas cylinder is initially 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of the original gas remains in the cylin u/ecquqpc 37 bnmczd;d+n11,der?   

  Estimate the number of air molecules in a room of length 6.5 m, width 5lkc)h fk 6ms7c +c-my3.1 m, and height 2.5 m. Assume the temperature is cc6 sk5hkyl)c -+mf7m22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is about one atom perwu)ls 9sn30dogo (j ,e4+qnfjk57z gl $cm^3$ 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 wvjwf+c*rou ) )iz3z)vacuum techniques is abo+)fiw3vr z cuj)oz *)wut $10^{-12} N/m^2$ 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 fuil1),s6l g8l-p xkwfy ll capacity of 5.5 L when 10 m below the surfac1ysl lg, x)p iwflk86-e, to what volume would his lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmosphere at a s vm4 :n(xlkjl/g6 9biz:e-cwnpeed of about 40,000 km/h Mxliv:c-g6n ( lzm k:be4wn/9j olecules (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 iigwqjoet/x )07i48jsncreased 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 volumeqdyl ujsr7 ,po(7 2xz/ 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 g bdk4qj ;8syz9qu8om bxmw14:q/z c:of atmospheric pressure at the surface of the Earth, estimate the total number of air molecules in the Earth’s atmosphedmj8kq:uycs:x9qoqzw b 1/44bmz;g8 re.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contained i 1)6pp: be+sg geke4uen 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 usescra5l+e 4 tndqs 3qix,f0h5/d in a hospital has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will th3 ,eh a5x0tfdsq+ q rl4nsi/c5e 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 liquid mercury a rx1ekhaf pbr-n9 w(x 3x8xzt-)ut)2 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 a .wu vdb96jblt+ vznvryf- /;4t 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 Ex8twnmtthz6 re12 0 x)arth’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 tight 8upuilg u2g2v;cs s*;ly 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 in the zxap q*e6*)wmpp5 o )nw,jt:pt;di,m 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 atm9r -uwy9a*45n )vsl*uy4wn:hnsgp y l 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 s ;*r3)5f tyr2k;rwru byjn4xis $ 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 suspe, (rutnu4f)fz 3 , g0b+gnzkqdnded against gravity by tennis balls thrown vertically upward at it. How many tennis balls per second must rebound from the lid elastically, asggqb k),z0+n4n, t fd(fz r3uusuming 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 (sphe*s+mgurfb6cgveo.7/ rical) 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 the surfacb .7esm6 rgco* +fgu/ve?    cm

  Calculate the total water vapor press w 5c.yya7u0hgure in the air on the following two days: hw gcy0a y.u57
(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 denm6brls t(zj:at q* jy-x*4;iqsity of iron at STP, and when it is a solid deep in the Earth where the temperat atqxy: b6lzsqtj;*r(i4m-j *ure 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 gasv249cks8 gcid law to show that, for an ideal gas at constant pressure, the coefficient of volume expansion is equal to 8k s9v2cg c4di$\beta$ = 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 prevenl3qtrtt,,:z w t rot and mildew. If the cell ,:3rt ztwqt,lar 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