Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the7-c6x2r cu dky periodic table or App- rkcdcyxu 276endix B.

Name several properties of materials that could be exploited to makf(ccvtmnyn .(zt 51 y3e a thermometn3tcv 1m fz5cty.y ((ner.

Which is larger, 1 C t/*hunapj5y j(j,a9 l$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B is not in the*; +1qp /xskhqee0 fazrmal equilibrium witqa+spz; /0 *kxqhe1e fh system C, what can you say about the temperatures of A, B, and C?

A flat bimetallic strip consists oc(q 2wg,0h+y,zau 2j,dvv zwb yt .l0xf aluminum riveted to a strip of iron. When heated, thew+y0z dl,jvvaxyh , wq20,z. ugb(2 ct strip 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 linear 73w npq 0 urxf /ifyu.lw,c8p8expansion $\alpha$ 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 thermostau.ilmf 9auzsdys(,bh5 c l:+c* v s61iqn /x9lt used to control a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of differenz c,sx9+mh.5lbns6di u :l9u *aiyqf1 l(csv/t 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 thatn ikuua,a3jyt(icfd 87)/)m w are fixed at the ends often have a section in the shape of a)jiun (,micuy7wfatk )8 d3/ a U. Why?

A flat, uniform cylinder of lead floazbl1, 9byn6 -mlyv)zwts in mercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glasuvwd,n5ly fe9806 yfgs thermometer is first placed in a hot tub of water, the mercl, ew6y y8gvn9u0ff 5dury initially descends a bit and then rises. Explain.

A glass container may break if one part of itgh6d0 n1+g wbjj3+ cwr is heated or cooled more rapidly than adjac0h3+jwjb1+d rgg6c wn ent parts. Explain.

The principal virtue of Pyr0v wqu6excy3/g. ajdu3h x .r7ex glass 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 resistance.u xgxcyra3hewq0 6d /7u jv.3 of Pyrex.

Will a grandfather clm sg(i9d,5bx wock, 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/;ked0fk kj0x badly the can w/dex0;k0kj fkill not stand up. What has happened?

When a gas is rapidly compressed (say, by pushing down al1: k3pi3pp5hwh j* 6+or vvpw piston), its temperature increases. 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 momentu1hpw+plp rjkh5i3* 63po:v v wm of molecules when they strike the moving piston.

Will the buoyant force on an aluminum sphere submerged in water fixd61 y6mgf5c d-:h yincrease or decrease if the temperature is increasf i-f6y x:6 ydhd1mc5ged from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows 7fgh : pll-m e904cucwfrom kinetic theory and the relation bet4uhl :g9l f7-pcme w0cween average kinetic energy and the absolute temperature.

Explain in words how Gay-Lussac’s law follows from kinetic theory.p65+-n74-uea lbqecbkp yifdd 93,+bm 6ohnp

As you go higher in the Earth’s atmosphere, t,q)vx28a.wlek bsr+zfvp4bx e(.1su he ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth r(oqn;gjl2 hk0 efers to the minimum speed an object must have to leave the Earth and never nj oq(glh0k2 ;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 quickpl50( /ipw xwwly than water at room temperature. What can you infer about the molecular properties of on xppww5w(0i/l e relative to the other?

Explain why a hot humid day is far more uncomfortable than a hot 0;auk5 lb;xr 9;1xq3gpcm cxadry day at the same tempe5qxxm;0cg;baa13x kp uc; l r9rature.

Is it possible to boil waterf6x y( yc8jr1q at room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days whenp :n./t 23m .giawvxqx the air temperature is the same but the humidity is different. Which is more dense, the dry air or the humid air at the same T? Expla3xpgvm t.ax./ :qwni2 in.

Explain why it is dangerous to open the radiator ca 4ws5gt.-xmf p zs(;wip of an overheated automobile engine.f. 4-;zwssiw(xp5 gtm

Why does exhaled air appear as a little w c70ja8m cw9bo)ae 2vuhite cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram)d mtkwo5 /ldqn)o*t6 copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare to the number i; ob1af+ogk5 7a7bt dvn a silver ring of tv7 1g +d;5obkoaat7bfhe same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this oni 9( i-3ft6 vruv:r5g 7venxco the Celsius scale?o5ec rn:7itvf i9r6(xvgv3- u    $^{\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*rkaco:a aly)rl kkp+o7 -5- i lowest temperatures 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 thermometeiol9:iua. 5b,to+ w orr, the alcohol column has length 11.82 cm at 0.o o:i.9i lw,+ otar5bu0 $^{\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 (2l7 ym cd.(my1dmr76q d0 $^{\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 appmv -b7blwj0u8p6ru wu.m1dk 2p 0. cxmroximately 300 m tall. Estimate how much its height changes between July (average temperature of 25°C) and January (averam-61r2m0kvdu pl 7m xj.bw08pbu w uc.ge 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 th* c1k y:haaj*xej3w p7m7sum6h5ggt( at are larger than the rivet hole are often used and thea* 6j1s* x cm3:h5pjh 7we(y7 muggakt rivet is cooled (usually in dry ice) before it is placed in the hole. A steel rivet 1.871 cm in diameter is to be placed in a hole 1.869 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 eyv* vuqcpy*gh/7 -es3q;c : bat 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 7-zg*dbapvc;w e 47 ssz)zip 2in diameter. What will be its change in volume if it is hea4s7;ws*zp7a ) zvb2dcpg ezi- ted from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350.0 mL of y7zx01nb x5t5 :2fsorpr (d6o)nvyb rwater 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 muewm0;g/uvzo (0 gx6 tf(ecs: L 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 ring g d1jfh91v*a umade 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 i3q i:+ -ahcv+ yp28 uklvgxd2mjo49art can expand in essentially one direction only, sho2 xv al3aqhcgyu4ov 8-d+ +rm2ijp9k:w that the effective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the densiz6q hay xm7/-qty $\rho$ 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 b 6v ya3ojvp9 *m+wp(xand width w has coefficient of linear expansion p (+bjpm9v ax3wyv*6 o$\alpha$ 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 solid,7u*yyo).ptgr2 pe o 3z $\beta$ = 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 oikprg1,rvxi ywpr.2 0 ts(+ i6f brass and keeps perfect time at 17pi.vkt spi w16r+rx ,ry i0(2g $^{\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 aii l 6prt-y8cmq1w;s9n inside diameter of 0.140 mm. The bulb has a 9yrm pws1q;6 -8itclivolume 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 m1z65 aoj+m fn-ckq)vcylindrical wheel of radius 0.41 m is rotating about its axle on frictionless bearings z-a+)n mco 561jqvkfmwith 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 h5t-rx *4rzg lnai8qq5h4g m np :*dy)length when at 15°C. How much stress is required to keep )a i-45mxgh:*rq pg dr ynt5l48znhq*it at this length if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-sectsmwxz,wfyg5 15ad w )+ional 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 cm at uf;19s,*ikfidp n.g fq: ag/f8i)n jt20$^{\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 j 1(u0rd2 gnsi-;lwxs ( 9f7hn 4pfyfzscale:
(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 Fahrenhe(8xg- fx6 aem*tv3+:pe(nr sd-td xupit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earzsc,1j1fsh o(pax)js+ud crz,- 0 ds:th 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 combustion engine, air at atmospheric pressure andjcqgzo e-p)6mwr-k16 a temperature - z 6moqr )-jc6egp1wkof 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 oxygmj l mzp 815u:thn:x5 :fs)zjten at STP using the ideal gas law.    kg/$m^3$

  A storage tank contains 2frk://5l ww*ub22xaxg or xo91.6 kg of nitrogen ($N_2$) 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 STPj(f/c k28agv2lqj( vjf)fu,neiqn90-/ aja p contains 18.5 kg of nitrogen ($N_2$)
(a) What is the volume of the tank? $\approx$   $m^3$(“Round to one decimal places)
(b) What is the pressure if an additional 15.0 kg of nitrogen is added without changing the temperature?    $ \times10^{5 }$Pa    atm

  If 18.75 mol of helium g2 gtsl0i,v uk;as 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 gas ljx 3x:0ujl4 xaly7:fat 385 xal74j 3l ly0fjxx::u K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg of,m2 os3syv/rjsf: 8d f $O_2$ 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 insidnq mff4z- . snd;yo(h76x ,jtz(kzg5 te the balloon, which makes i-s6 zz7.4hm,;g (nt5zft f( onkjqyd xt less 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 at pet , oc426ns4k,zcn4)txq hx5 sjc5 c15 $^{\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 atgbz r6axqtp,p n(+/4sua87b 0wcm ).u5rw etw 18.0 $^{\circ} $ C and an absolute pressure of 2.45 atm are compressed to 48.8 L and at the same time the temperature is raised to 50.0°C, what will the new pressure be?    atm

  A helium-filled balloon escapes a child’s hand at sehm u + npi;/*acrod:2qa 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 modc zfi2ezxr(oi029 c e/(ty2j lecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How t/re / ccmx2j6lilcu6723rspmany molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) molebk9yb-mr0t0o -34u x w8p o75mpla ovos,    $ \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 5.1w-s6; npjbw1g$ \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 ea/uzvh9)w/,)e lsv9ybdu.y ob ch 2.0-L breath you inhale that were also in the last breath Galileo took. [Hint: Assume the atmosphere is about 10 km highbyvey slud9/9.v))o /z b wuh, and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the averx-j/2z)2 rse bz:),.yiy zdrij0c dunage translational kinetic energy of an oxygen molecule at STrri ):.0ubs z,cejydn)2-j 2z/xyiz dP?    $ \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 .vs8wxp ;o/z;yr m-k.bwz q5vhelium atoms near the surface of the Sun at a temperature of abb8;ov.k;yww .-x5mpzqzvs / rout 6000 K.    m/s

  By what factor will the rms speg 49mp q:qrow) py:bb5ed of gas molecules increase if the temperature is increased from 05m 4yqwp: )brgo9bpq: $^{\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 a ja78+ oeir4-b-rt xounits of km/s: 6, 2, 4, 6, 0, 4, 1, -baxjtear8- o47r+oi8, 5, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at 20.r;xwmlvfm dj/j;+l2 4 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,v3 ,i jb(wyi z0n3ebrza4m5u. by what factom(a3u b3, 4i bwrnzz.jiy0ve5 r does $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is given by ;*i a6j xpm4p 4gzbx:gk)nlp;$v_{rms}$ = $\sqrt{3P\\rho}$ where P is the pressure in the gas, and $\rho$ is the gas density.

Show that for a mixture o6vv6k8yxb j jew /b94jf two gases at the same temperature, the ratio of their rms speeds is equal to the inverse ratio of the squ j4v69ebwbkx yv68j/ jare roots of their molecular masses.

  What is the rms speed of nitrogen molecules contab:b.xh ed/+wzined 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 oxygen molecule atl,8l ,a6)mhtaz ba ymt.7m9gc 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 STPr inf8fj z1ms z,anlkos653* -?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose mo vh-jhfn-1u- rlecular mass is 89 u in a living cell at 37 h-huv1 j--rfn$^{\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 written P uy);kzt,jd,z 8kwmi u4or91 x = $\frac(1)(3)\rho v^2$ where $\rho$ is the density of the gas and v is the rms speed of the molecules.

  The two isotopes of us25:2g4y iz-c ool w)rxmqp+cranium, $^{235}$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 phap , q/jtgp/ toet7 /10nv4cpoases 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 t*.bu6qt 6makbyon; v5he temperature is (a) 9. yqv;on6 bku*6 tmab50 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the 9 e eu*ucip) xai-9-lehumidity is 50% on a day when the temperature is 25 c-9eu*xlei )p-uae 9i$^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a 3 pywz5i*p,skeq; gccegr0 u:b3:g4c place where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular yrv:ga:jzq19j q6uz 7 place in the mountains is 0.72 atm, estimate the temperature at which water boilqzaju9:r 7 yvjg1: q6zs. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day whenp0 tw 0i4g/7e+uogs yx the partial pressure of water is 530 Pa and the rela o 0gpw+te4usy7xi/ 0gtive humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day (ruuhr91uci4 p+y5civ:pst 1 when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximk8 uxu1dg;rw1 ate pressure inside a pressure cooker if the water is boiling at a wxrk1uu1g;8 dtemperature 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 volgelzh, t 7kn0x+sb1(fn -, bsyume 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 obzfe, t 7ykf.:1mz6qcf 5 $^{\circ} $ C is drawn into a building where it is heated to 25. What will be the relative humidity at this temperature? Assume constant pressure of 1.0 atm. Take into account the expansion of the air.    %

  Estimate the time needed for a glycine molecule (see Tably t-wg:/ utpk-f/rtz2e 13–4) to diffuse a distance o:r--2kz fgy tpt u/wt/f 15 $\mu m$ in water at 20$^{\circ} $ C if its concentration varies over that distance from 1 mol/$m^3$ to 0.4 mol/$m^3$ Compare this “speed” to its rms (thermal) speed. The molecular mass of glycine is about 75 u. t $\approx$    s ([color=rgba(0, 0, 0, 0.85)]Round to one decimal places) $v_{diffuse}$    $ \times10^{ -5}$ m/s
$v_{rms}$    m/s

  Oxygen diffuses from the surface of in jhokwjnj ic/-0*8u+ asects to the interior through tiny tubes called tracheae. An average trachea is about 2 mm long and has cross-sej h*ocuwki-80/ +n jjactional area of $ 2\times10^{-9 } m^2$ Assuming the concentration of oxygen inside is half what it is outside in the atmosphere,
(a) show that the concentration of oxygen in the air (assume 21% is oxygen) at 20$^{\circ} $ C is about 8.7 mol/$m^3$ then $\approx$    mol/$m^3$(Round to one decimal places)
(b) calculate the diffusion rate J,    $ \times10^{-11 }$ mol/s
(c) estimate the average time for a molecule to diffuse in. Assume the diffusion constant is $ 1\times10^{-5 } m^2/s$    s

  A precise steel tape measure has been calibrated l(z) wiz/by7.lv lg);qjses 6at 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 calibzl.( on 9 )d;uc-zop3hu: mkesrated 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 i(vr :7uvqzyqc g6s (0calibrated at normal room temperature. How much error will be made in a recipe calling for 70u c :q(y6r(zgvqvsi300 mL of cool water, if the water and the cup are hot, at 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in a helium gas cylinder is initially 28 atm. After many g7 0dywtq5. ;nd(c zvgballoons have been bl(d 0 gqwc .yg5vtz;nd7own up, the gauge 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 leak 1hl8h1hl w/ngth 6.5 m, width 3.1 m, and height 2.5 m. Assume th /18hlk1h awlhe temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of rcqhyq 5 8n6dcx q-*ufa8t0-kmatter 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 techniques isu 7t :i2/pmfss about:tu 7fs/smp2i $10^{-12} N/m^2$ At such a pressure, how many molecules are there per $cm^3$ at 0$^{\circ} $C?    $\frac{molecules}{cm^3}$

  If a scuba diver fills his lungs to full capacity of 5.j)osary;dom6y s*g8 m 6n(k03zbz(qk5 L when 10 m below the surface, to skr8n6 *od yk qzzs3 g6majmo0b(y);( 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 E)np-euh s;qeqv98b y r2+;davq+ +xx6zz( astarth’s atmosphere at a speed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this speed correspond to what temperature? (Because of this high temperature, the nose of a space vehicle must be made of special materials; indeed, part of it does vaporize, and this is seen as a bright blazevhxzsdyvz ;b+ x6p2a-r(q9u e)8s+ ntea +qq; upon reentry.)    K

  The temperature of an ideal gamaz pqw- 1 6q//wcre9xw)(qz is is increased from 110$^{\circ} $C to 360$^{\circ} $C while the volume and the number of moles stay constant. By what factor does the pressure change? By what factor does $v_{rms}$ change?$\frac{P_2}{P_1}$ =    $\frac{(v_{rms})_2}{(v_{rms})_1}$ =   

  A house has a volume ofj/1 *9 pzidkko aywe:no7+.lz 770m$^2$ (a) What is the total mass of air inside the house at 20$^{\circ} $C?    kg
(b) If the temperature drops to -10$^{\circ} $C what mass of air enters or leaves the house?    kg

  From the known value of atmospheric presig2 ptpo424ub sure at the surface of the Earth, estimate the total number of air molecules iup4 gb2pt4 o2in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contain5u su)dg912exzp h+ar ed in a 7.6$-m^3$ volume at 4.2 atm if the total amount of nitrogen is 1800 mol?    m/s

  A standard cylinder of oxygen used in a hospital has gauge pressure =vf1dnw 9f39ss 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if9sdvfs9w1 n 3f the flow rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of l lx-( t*yzcux9i- p ;mw7idk9biquid 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 ma lc8-cn0c2f ee ad7*at 0$^{\circ} $C is 0.68$ \times10^{3 }kg/m^3$ What is the density on a hot day, when the temperature is 38$^{\circ} $C?    kg/$m^3$
What is the percentage change?    %

  If a steel band were to fit snugly around the Earth’sm9byj(/1t9 d14zsi*vm duea o 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 o3 xrq:/sq a 4:d-;wncs4ljlw 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 inxo*l1c7 vms5x8fv ,l h 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,xv qvj9-h8-h39hxxez has a 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 Eaac4 qxikb+*w n;km2 g5rth 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 suspn3. cbtjqi a7/ended against gravity by tennis balls thrown vertically upward at it. Hoa3.jc/b7ti q nw 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-dq;l a tfx*fi+r(6;w)lmi:xkd iameter (spherical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and wli q*lxr 6t+xf (;m)ak:fi; dthe air behaves as a perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total 3ufa* dtns n xb:5q69v7x -stnwater vapor pressure in the air on the following two days: t6nx ab7dvx s:5u*-3 sqtn9 nf
(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 of9ksah)i 3:ea r iron at STP, and when it is a solidk a9)3ai r:hes deep in the Earth where the temperature is 2000$^{\circ} $C and under 5000 atm of pressure. Assume the bulk modulus (90$\times 10^9N/m^2$) and the coefficient of volume expansion do not vary with temperature and are the same as at STP.    %  ----待选择----decreaseincrease 

(a) Use the ideal gas law to show that, for an ideal gas at constant p;8 je-m+oxub uressure, the coefficient of volume expansion is equal toouj;u8 bxem-+ $\beta$ = 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 c fo+z qpin 9c+utc27lqad9pw. f5* 0xtellars to prevent rot and mildew.p. lztda+iq 7*fq0t92uc cxn5op+ f 9w If the cellar in a house (kept at 20$^{\circ} $C) has 95 $m^2$ of floor space and a ceiling height of 2.8 m, what is the mass of water that must be removed from it to drop the humidity from 95% to a more reasonable 30%?    kg