Which has more atoms: 1 kg of iron or 1 kg of aluminum? S 7zue* xm;-leoee the periodic table orzeo 7lx-m *ue; Appendix B.

Name several properties of materials that could hufx+1at hl)5 be exploited to make a thermometex 1)a5tu+ lfhhr.

Which is larger, 1 C 558j hr xiley j-lf/.s .gk4sg$^{\circ} $ or 1 F $^{\circ} $?

If system A is in therqp4 4yx9ub l4 c(;ayglmal equilibrium with system B, but B is not in thermal equilibrium with system C, what can you say about the temperatures of xu l y(9q4bacl;gyp 44A, B, and C?

A flat bimetallic strip coyaw-4k ry v12 e,skp:ky4j*t dnsists of aluminum riveted to a strip of iron. When heated, the strip will bend. Which metal will be on the outside of the ckwy1y r, kj:2kt4p-d4e *y svaurve? [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 coec4ggt)bx4ee,gv .nm i/ zn/m,fficient 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 diagram of a simple thermost/ i(kmrb czla y8;0uxccn9ugj)6. dl5at used to control a furnace (or other heating or cooling system). The biu9)n blgx dazmcky5i;u 0lr8j6.c( c/metallic strip consists of two strips of different metals bonded together. The electric switch is a glass vessel containing liquid mercury that conducts electricity when it can flow to touch both contact wires. Explain how this device controls the furnace and how it can be set at different temperatures.

Long steam pipes that are fixed at the ends often have a section in the shape odq1(tk5 q*tk ef a 5tkk1q *ted(qU. Why?

A flat, uniform cylinder ofhws+nkwdt.2 b0o (qgz )xwa v4qj .15z 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 is0.5j mck-6lzq2 r ,df/we9dc4xlf mdo first placed in a hot tub of water, the mercury initially descends a bit and then rises. Explaid0,2fkj -xl.9e6mdql wdf 5c4c r/ozmn.

A glass container may break if one part of it is heated or cooled mo(e v8fwo)gacq7/cp(c5ba (suum0f7p re rapidly than adjacent parts. Explain.v)m p(ecwsgo8(q /5 c ua(c70b fuap7f

The principal virtue of Pyrex glasztt;hi ;qc 93+nq1nkf s is that its coefficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resikhzqnqn31i + cf9;;ttstance of Pyrex.

Will a grandfather clrz-zyo/5 z ,hv.wp) ikp1 ,hevock, accurate 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 badlyoj n-f48b5djsp .l o1o the can wiln1ljb5oo 8fj o- 4sp.dl not stand up. What has happened?

When a gas is rapidly compressed (say, by pu. 7rw jx uh4t2qft*lv;shing down a piston), its temperature increases. When a gas expands agt;7vhwx*. l24tr q fujainst 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 forcefxf:pzkl.*l13 h 8sl)l msehqf/cr) 7 on an aluminum sphere submerged in water increase or decrease if the temperature is increased from 2lqls 3s ) hk:ff)zphe 7.c*lxmlf/8 r10 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law f2 dkymj,da)rb i--z8f ollows from kinetic theory and the relation between average kinetif zm8 -dajb2) -y,rdikc energy and the absolute temperature.

Explain in words how Gay-Lussac’s law follows from kinetic th4 rbj;w-lq/ eheory.

As you go higher in the Earth’s atmosphere, the ratio of ovsp 66i9p5:fzyo 2ac. as *wl$N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed an object must have toni(s8wr :. pyaem:;*0 aqi zka 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’snqa y8wmesi.z*ir a;ka(::p0 smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at0miqcoii+h1 476f c hn room temperature. What can you infer about the q 10miinchf+o i476hc molecular properties of one relative to the other?

Explain why a hot humid day is far more uncomfortable than a hot unni+hvncnx(+dg ;, .z;di3f dry day at the d+ni,v3ndc;z.nnig hu(+f; xsame temperature.

Is it possible to boil water at room temperaturetl (0e6sk8k0 f2-kxs *xnsot c (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air+.6 h s oeoyzai2glnbuf6y;*)sk*gz1 temperature is the same but the humidity is diffeui s;y2egoz6zh a .gfsn* o)1b+6k*l yrent. Which is more dense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap1j zrq)t)4 vkl of an overheated automobile engik l)rtzv)4 1jqne.

Why does exhaled air appear as a little white cloud in the wintesep3lc*-cz- ,,r )) q1uz h dooyx0dlvr (Fig. 13–28)?

  How many atoms are there in a 3.4-gram c09d0 6 jl4brjr qby)-xypsa.fopper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5 +l qlo hkg1m9rd3:cg7xwi3ju3*x1ku-gram gold ring compare to the number in a silver ring of the same masclwo7j qi*9 uugrxdm1lxg3h3k k 1+3:s?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this o,xyv9/eg;t1 msi 0ewl n the Celsius scale?exe ytv,/ 1 miwg9;0sl   $^{\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 temperatureqhpwgnw.h36 -uo2) m hs 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 alcohol5y)gglw6 wfg 8 column has length 11.82 cm at 0.ggy6 wg5)w8fl 0 $^{\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 rqka06d04bo +nxtg(q long (20 $^{\circ} $ C). How wide should the expansion cracks between the slabs be (at 20 $^{\circ} $ C) to prevent buckling if the range of temperature is -30 $^{\circ} $ C to +50 $^{\circ} $ C?    m

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

  The Eiffel Tower (Fig. 13–29) is built of wrought iron approximate0 -zut,kf28b;t)bi ja es:f-b jyayb5 ly 300 m tall. Estimate how much its height changes between July (averi0,f;uf8-tj s2zb kye- ajt y5 b)ba:bage 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, wz419yeswg(.ju kx( d rivets that are larger 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 z(ky4eu .(s1w gd9w xjis 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 u,gforsr ;1p/4 $^{\circ} $ C is $ 1\times10^{3 }kg/m^3$ What is water’s density at 94 $^{\circ} $ C?    kg/$m^3$

  A quartz sphere is 8.75 cm in diameter. What will be its change in volu 9moi s1v6p5rxme if it is he5mpv9or16i sx ated from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 35 q:wh /c2iph(1o0h+v1mzb wbuz;cv;x 0.0 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 s)i g::f-y .xzrd46f( gzkjkh55.50 mL 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 rii)w3:ufy1es :eb(;d ymxlep : ng 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 flxyl(uu9* d/in a long, narrow vessel so it can expand in essentially one direction only, show that the effective co /*x(ulf9l udyefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the densit 89(qgz29svdydv-piw4e o4uvq uv tl/h p+1)qy $\rho$ 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 4 pnmmm hnd r/*zb+ 7pti)z75pexpansion / nmrdtzmh+ibz 5n7 7)m4pp*p$\alpha$ 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 soltrq nez4 94 :p jr4wbvk6+c:ttid, $\beta$ = 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 k63 iid)uuasy 5,o7trfeeps perfect time at 1rd i)6yti,u7 5uoafs37 $^{\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 i vtvwzca /1dz(pt56v/ nside diameter of 0.140 mm. The bulb has a volume w6p( /t/1ztvz vdv5ac 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 abozbx6q: l,i/ 9kw*d j,rl u)eozut its axle on frictionless beariq9r,i)lb/zw ,e: *luxo zdjk6ngs 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 de),o:3q0 hgfzpkk2 q( m6hnlm 9y/ujrisired length when at 15°C. How much stress is required to keep it at this length if the temperh ikkljh3 qyqm0(9u) 6pz2o g: /frm,nature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-sectional area 0a0e-qbk ym z)xezul778h5v+ohf 7c 5jj7o ,gr.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 cm syzwe):6/eas 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 scal25o cp eqse26 jw.gkdq2c /s,ie:
(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 wha:di z -h( 6v2z l/;ms/oisltu*jiyc8trdjx+,t temperature on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun are about 400th ng.lzl21j*4o (fsb 0$^{\circ} $ C and $ \times10^{6 }$ $^{\circ} $ C respectively.
(a) What are these temperatures in kelvins?    K    $ \times10^{ 6}$K
(b) What percent error is made in each case if a person forgets to change $^{\circ} $ C to K? $\approx$    %(Round to the nearest integer) $\approx$    %(Round to three decimal places)

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

  In an internal combustion engine, air at atmospheric pressure and a temperat.yc(rhezvnwffkm 37)q 0ub:( ure cr kh7zq b f.0meuwyv((n:) 3fof about 20$^{\circ} $C is compressed in the cylinder by a piston to $\frac{1}{9}$ of its original volume (compression ratio = 9.0). Estimate the temperature of the compressed air, assuming the pressure reaches 40 atm.    $^{\circ} $ C

  Calculate the density of oxu:ncsa5yedac s2e2 6 ;l;o2unygen at STP using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of nitrogjgkp+g h(af 7:en ($N_2$) 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 k9a abab.482gbxx eb ced8c6i7r ,x3byg of nitrogen ($N_2$)
(a) What is the volume of the tank? $\approx$   $m^3$(“Round to one decimal places)
(b) What is the pressure if an additional 15.0 kg of nitrogen is added without changing the temperature?    $ \times10^{5 }$Pa    atm

  If 18.75 mol of helium gas is at p aj)nj5 oicz1mzt6k8)hv40y10.0$^{\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 argonsm21hjgs ooq j16kc7 - gas at 385 mq6-2 oh1 s1sckgojj7 K?   $ \times10^{ 8}$Pa

  A tank contains 26.01sk v, qbahq,r *m(oszq3) 75,vfoffg 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 heating the air insideu(c j2ugktm2t78z s mvb9j *0p the balloon, which makes it le mz(209kgtm jcv2s*j7uupb t 8ss 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 witzodxt*;/r;ipmb a5*3ut fly, h 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 at 18.0 es 7 wqds5 j1(rr5f 2as4o,gtz$^{\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 ain r.)h0ww );whb oxcyqf2rx*b+( *xdt sea level and 20.0 $^{\circ} $ C. When it reaches an altitude of 3000 m, where the temperature is 5.0 $^{\circ} $ C and the pressure is only 0.70 atm, how will its volume compare to that at sea level?    times the original volume

  Calculate the number of molecules / g, czn1)cuukhb-7q hgjc5p-($m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How many molecul3vd0r-x mo s gy4,jem5es?    mol    $ \times10^{25 }$ molecules

  Estimate the number of,fgf q)7z ot3;dr 2dk63bt, ; aykomdu (a) 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 5.1hqt+ks-wqg vk10 ;c5 p$ \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 66rsvn1s ;o en* qdm0linhale that were also in the last breath Galileo took. [Hint: Assume the atmosphere nds166so ;*mn lq 0veris about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of an oxygen molecule at cw iioe0++(a:xylx wvk1,xz0 STP?vw00c, oi1aixe :xkyzw++(l x    $ \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 surfac totwwio )55:qe of the Sun at a temperature of about 6000 K. ttq oi)5o5ww:    m/s

  By what factor will the rms speed of gas b5 piql8rw/..l pf2pw molecules increase if the temperature is increas wb lp52pq.fi/rlp8.w ed 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 units of km/s: 6, 2, 4, 6, mhy14i9rzpzp :l ej0b97j6y b 0, 4, 1, 8, 5, 3, 7, an6l14 z9j 7bb0y:yrzi9mejpp hd 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molec uw6u0fdl+qw 5u9j pyja;*fx9ules in a gas at 20.0 $^{\circ} $ C is to be increased by 1.0%. To what temperature must it be raised?    $^{\circ} $ C

  If the pressure of a gas is doubled while its volume is held constant, by4 gi /u jasn5sdf1qs-rf*th+7 what factor does nu stf/7s5d hs+jr4qig-a f 1*$v_{rms}$ change?   

Show that the rms speed of molecules in a gas is given.,*vhjhwy e,b i.,bqr 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 temperatar skg(,7 /kvrure, the ratio of their rms speeds is equal 7k ,(ragsvr/ kto the inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen molecules contained in an 8.z2x2za. xpr(prgue 0/5$-m^3$ volume at 2.1 atm if the total amount of nitrogen is 1300 mol?    m/s

  Calculate (a) the rms speed of an7uea;hk ;f.(-rth/d qhtsgv.gy93q y 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 btge -b qx6vn51 *nwwq,etween nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular mass is 89 u in a li9).g o 8hog46um yetybn8,o xoving cell at too y9.4gun 6o8bmexgy8)oh, 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 writtejfiny72y f.) an P = $\frac(1)(3)\rho v^2$ where $\rho$ is the density of the gas and v is the rms speed of the molecules.

  The two isotopes of uranium,jcxe((1r gdb:i4 a m,b $^{235}$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, ini dz/ 8lzq40zci9s th-iry9d* what phases can $CO_2$ exist? (b) For what range of pressures and temperatures can $CO_2$ be a liquid? Refer to Fig. 13–21.

Water is in which phase when the pressure is 0.01 atm and the tempvz t:;fq0yze;i6t s1gsnhq2 rz1)6 jderature is (a) 90 e;16f ss h; qntvq2rtgiz1 d jz6:y0z)$^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (a pc+ n)fuf7 y8 32fz, qxguwuolw;89eppproximately) if the humidity is 50% on a day when the tempeq oeu c,7f)p;u9x fwnf w28p+ly8ugz3rature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where watexx )6cv7gyg)b1umae1 r boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is 0.72 atm, e2z g; br.a2d dm xz*6ih,je*ifstimate the temperature at which water bg*m dij*xz ,zdb.fahr; i2 e26oils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the pus: 3pkhe6f8u artial pressure of water is 530 Pa and the relative humidity is 40%?hfuus:36k e 8p $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when+wfnm6 +bvn;45fckrn i ))tty the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cooker if the watergh*ovr1r c *1ct wz9zhamz4oyh 8 s*-+ is boiling at a tempe-czcz* mh1ov*1 try g +r89hzshowa4 *rature 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 j4e t zmxzk49xm c):i6/+rrdt 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 des e m;/ry 43jt*jujh9qw point 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 moleculs st 6i,* qspoj*dxw:(i6wwc5e (see Table 13–4) to diffuse a distance of 1wx6q5,stidoic (* :w *wsjs6 p5 $\mu m$ 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 i ,wzn;z;xqp*agvx-vzn 2w p0 9nterior through tiny tubes called tracheae. Anz9*v qv p paxxz-2wwz,;;0n ng 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 h adnzb6yr0g 7 r**luq3as been calibrated at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A precise steel tape measure has bjd/fhpo p.q( lqr8;/jeen calibrated at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A Pyrex measuring cup was calibrated at normal room temperature. How mua:yl0z g8+sh hch error will be made in a recipe calling for 300 mL of cool water, if the water and th lz08shah g+:ye 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 z,wbf2ox(lc8 a8q0hhatm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. Whaz,a w8c02xfqh(o b8lht fraction of the original gas remains in the cylinder?   

  Estimate the number of air molecules i1 +xi c;r7ji 8xulrjm:n a room of length 6.5 m, width 3.1 m, and heigh ulc71xrii 8mx:jr j+;t 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 about oo/mnju; (vpu5+5 ffnvne 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 0uzm0 clnvjg,:y .. vgo-; lf2mrwmn3is abou0n r llgjc.;y,o2n0u:mmv-w v3z gmf.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 lungs09ob )fmc- qon to full capacity of 5.5 L when 10 m below the surface, to what volume would his lungs expand if he )b9ocqof- m0nquickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmos 7p y6bhb:f0uqphere at a speed of about 40,000 km/h Molecules (assume nitrogen) striking hfy7qu6:bb0p 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 increased syi qm+;ehlcw7* mq,)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 770mt8jfd +6pz g5i$^2$ (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 )nh u z;a/4iwadtw l12the Earth, estimate the total number of air molecules il1ud ;)2ia zt4awhn/wn the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contained in j0p2gx;a;h as3 5zwfya 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 i8/va(yd 83l jlzr:t3obsz5 c sn a hospital has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure, is co ov8:(t/l3lcza yzb35s jr8dsnstant at 2.4 L/min. $\approx$    hour

  An iron cube floats inn7;nc vaav;xn 9;ajfa) 1gju+ a bowl of liquid 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 akbp3q:;uu4h pzk ,/knt 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 38k.g ;puavhw7c3onrto fit snugly around 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 tightly onto a gh5/d2r5pb )po7uvwg z: y7 snxlass 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 standgbala i1m a1*-ard, adopted in 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 atm at1 usco)7-ljnuvz6,b n 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 f*z (+zpsq; , jh87asw z6bly1(tfrkj 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 agakpggd 6m.z96 kinst gravity by tennis balls thrown vertically upward at it. How many tennis 6dk mzp6k .g9gballs 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) bubb)f:omj dwumjr2b9 x,9jl;g k *le 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 surfaj )ju;* :2olxjgrw99md ,f bkmce?    cm

  Calculate the total water vapor pressure in the air on the following two dayy*k+bm /0be 1lc tn1sys: b0e1c /k*+ysmylntb 1
(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, gpnk+ ;2n,kcq;o lw i9and when it is a solid deep in the Earth wherlk+2c ;;wo ,9ikqnpgne the temperature is 2000$^{\circ} $C and under 5000 atm of pressure. Assume the bulk modulus (90$\times 10^9N/m^2$) and the coefficient of volume expansion do not vary with temperature and are the same as at STP.    %  ----待选择----decreaseincrease 

(a) Use the ideal gas law to show that, for an idebmqa h / +2g p+82roh.cut0trxal gas at constant pressure, the coe8o/g.h+2pmt b hatux crq0r2+ fficient 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.