Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodic9vyqzbyfbl3m 4 .t24m9 .*iysoh f ph: table or iv4 p 3bysm: o.zy9*9b4.myhltffh2 q Appendix B.

Name several properties of materials that could be exploited to make a thermometnaseu* d: 2pz9hnsp(0 er.ph2*0: n 9(an uspzeds

Which is larger, 1 C :,pq* uho /hik$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrsatrh4 x5ph34 zq7 2;uhujwy )ium with system B, but B is not in thermal equilibrium with system C, what can you say aqxu );5 w 74r42hhuhzj3patsybout the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to a strip of iron. When2a8 mats0i(myt1 hr(o heated, the strip will bend. Wa 2tm y(a i0h(smro8t1hich 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 coeffidknr(c6v sl x2c/v :+bcient 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 thermostat used to co kx4,xq1r-c;v rrib8h6eb*v qntrol a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch is a glass vessel containing l*1cvh rxbq vr6qb84 rx;-,ikeiquid 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 ayi7n e5 1v xczk eo)2o6wohha.;9c( vh section in the shape of a U. Why?;6k v5ezhncoy92.ovi7h() a ho1xw ce

A flat, uniform cylinder of lead w o)f rns0a 61:vw(vrnfloats in mercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-gzr9x vlbpbm43u,:; +qi 7n qrin-glass thermometer is first placed in a hot tub of water, the mercury initially lrb b:ri7qv,+ ;3 4zn mxpqgu9descends a bit and then rises. Explain.

A glass container may break if one part of it i,t5-r7i yc ypxs heated or cooled more rapidly than adjacent parts. Expla7i-,5pryy tc xin.

The principal virtue of Pyrex glass is that its coefficient 4e ym4xk1bb1s *3hcnlof linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased he x 4bkncsml1*b4ye13 hat resistance of Pyrex.

Will a grandfather clock,h mxo7q/)n( ,laqlsc4 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 o;/9x3 uj 6ia7/gh(e m9upf2jm xefykka q 4h8badly the can will noma f8y6 maj4hx/ up/9jge32q;(e xofi79hkkut stand up. What has happened?

When a gas is rapidly compressed (say, by pu;kuda1 lt /ei:shing down a 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 wha1u ;/dlk aeti:t happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force on an aluminum sphere submerged in water incr* l1ockq:s*nm)9u 7vedv:o afease or decreave7u*v 9:sq1omkacn)o:fl*d se if the temperature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinet31swhz- wp:;4eu q jps .)xsxzvl. +p d8rxv1yic theory and the relation between average kis4pdz31e1 vwylqr wuh sppj).-8 .szx+:v;xxnetic energy and the absolute temperature.

Explain in words how Gay-Lussac’s law follows from kinetic theory.j4 lo;m58 ; ztilh vzlr7qtp/3

As you go higher in the Earth’s atmosphere, the snc2wpttq-3:pyedzazi5f- 3 /u-w f6 ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed an object must have to :j9:w8 v /fjjn r66mgubp*-fgla;ehc 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 mass. Explain why thej / lujnrcpfmwhfa69jeg6b8-:: v*;g Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at room temp1iff8gofi 5 hgs;+r.terature. What can you infer about the molecular properties of one relative g1+hsr5f t ;oigffi.8to the other?

Explain why a hot humid day is fa3nobg,m j:s(f4de tz/r more uncomfortable than a hot dry day at the same temper:m4z,3sfdjog/ tn eb (ature.

Is it possible to boil waterhatqb6d)j h 9*(ql*is at room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but;3qrd+r(.aiz)k 8 y eljaoow:pmy(d+ the humidity is different. Which is more dense, the dry ail;):ayer+rp 8y(+3m zk odw(jqia o .dr or the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap j(dlwn-d5/w4m0loe gof an overheated automobile engilm0l4dgdojw-5 /(we nne.

Why does exhaled air appear as a little white cloud 3cm1a1 dxi3nnxly g)e: )e cn3in the winter (Fig. 13–28)?

  How many atoms are there in a 3.0e o74zwoi3fp4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-6z6,j f sc( y.f6yv71 w6 jdeptjdq6angram gold ring compare to the number in a silver ring of thf6.f e( djwp6 ,sdj vyq7tc16yaznj66e same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is t adgbu5z.2fp- his on the Celsius scale?2b azfp 5g-du.   $^{\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 lok o 1)qkx8t2jgwest 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 o,j/tw ;m1y/b+nqf eythermometer, the alcohol column has length 11.82 cm at 0.0j,/yfnoteb/q 1;w ym+ $^{\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 built9rdw;ah3hld. q6+qu ij(q 7h -g rejy+ of slabs 12 m 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 approximately 30:n o g-tlfs91f0 m tall. Estimate how much its height con1-9 sf:fglthanges 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 larger than the rivet hole arel 93;fn xwg.mh 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 to be placed in a hole 1.869l f3.;whxn9gm 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 a 6spbgdl+0nm */ra *b.w* eiwqt 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 volume yjpq ,2pu ir-)if it is heatedj,-u )iq2yp pr from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is fe hpx 9:k zz5bpin,z(rsp-9x t*a6n ;nilled 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 wate)mbu8bi9j,bvi*.xt k r 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 mad;9;d glnldl:+ bqwdo (e 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 contaili y og.x4f 88gtb:e,zned in a long, narrow vessel so it can expand in essentially one direction only, show that the effebig8t,:8 z xf .loyg4ective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the dens ebg6c*grbo8,tz39mv ity $\rho$ 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 w7ze uo:hpicd2 -)c5i linear expansion uo)-:ip7h 2ic5zw dc e$\alpha$ 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 isotrop xppu/*ka 9caw;f ;6b3dqgvz9ic solid, $\beta$ = 3$\alpha$ if the amount of expansion is small. $\beta$ and $\alpha$ are the coefficients of volume and linear expansion, respectively. [Hint: Consider a cubical solid, and neglect very small quantities. See also Problem 18 and Fig. 13–30.]

  The pendulum in a grandfather clockm j/r1 2hsll1u is made of brass and keeps perfect time at 17 u/sl1mrh j1l2 $^{\circ} $ C. How much time is gained or lost in a year if the clock is kept at 25 $^{\circ} $ C? (Assume the frequency dependence on length for a simple pendulum applies.)$\approx$    min(Round to the nearest integer)

  (a) The tube of a mercury thermometer has an inside diameterrsg0 dwj6jx./x 5 30dlxo-cdp of 0.140 mm. The bulb has a volume of 0./rdg5.6jpjwxd x-003l x odsc255 $cm^3$ 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 c3g c h(vf:nm9tylindrical wheel of radius 0.41 m is rotating about its axle on frictionless bearings with angular vtf( :gmc 93vhnelocity $\omega$ = 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 length when at 15°C. How much stress is reqrj 5o -zw89nltf*2 djypufq7-uired to keep it at this length if the temperature inj9qp8f7t o* w2 r5ylj uf-znd-creases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beaq-p/c(xcj d 5fm of cross-sectional 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 20(4b96bbia9ttenx ubx8 g8w.me :l dv)$^{\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 Kelkg1v9x 4 l;gj p7wdr.d,ns.s.rhbi+kvin scale:
(a) 86$^{\circ} $ C,    K
(b) 78$^{\circ} $F,    K
(c) -100$^{\circ} $C    K
(d) 5500°C,    K
(e) -459$^{\circ} $F    K

  Absolute zero is whau7b np6w )p.b mnmrxbq(,,s)gt temperature on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures nh -lijd +qx) xy.z+zb;e(ypyo 1)l*c in the interior of the Earth and Sun are about 4000$^{\circ} $ C and $ \times10^{6 }$ $^{\circ} $ C respectively.
(a) What are these temperatures in kelvins?    K    $ \times10^{ 6}$K
(b) What percent error is made in each case if a person forgets to change $^{\circ} $ C to K? $\approx$    %(Round to the nearest integer) $\approx$    %(Round to three decimal places)

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

  In an internal combustion engine, air at atmospheric pressure and a tempo;0aeg:4( jzkh5 (-o go5,m h dozij1yu9vhlaerature of about u dev-a ghajio5h (m9yo,05 ook( :;1zz hjlg420$^{\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/d4 nbm55o, qctus/vn5gyme4 ideal gas law.    kg/$m^3$

  A storage tank contains 21.6nw m chml1l1tjs0p.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 STP cont81awsks 2jcc-zlf u 7,71 9abgg dnvc8ains 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 heli1 k3pg.ts, mbkum 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 insupyqbr;w fk2o1r9v010cy*bi+yja6 fide a 35.0-L container holding 105.0 kg of argon gas at 385 f k 11vo0cbrp*u+wr0y629; ybjq yf aiK?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg of uv r32l1la4d(q b ob4w$O_2$ 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 bysbwg.8kg(; zgv :rq; uoyant lift by heating the air inside the balloon, which makes it less dense than the air outside. Suppose the volume of a balloyszv .gk:g8( b q;grw;on 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 l9 ejf ic (x:a5.zqx o+)xac1+jbij*xair 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.nygp/8o *)ol+ugm5 s p0 $^{\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 ) qujkgjj 6igif1e/ya.2 b :t+s*nhb7’s hand at sea level and 20.0 $^{\circ} $ C. When it reaches an altitude of 3000 m, where the temperature is 5.0 $^{\circ} $ C and the pressure is only 0.70 atm, how will its volume compare to that at sea level?    times the original volume

  Calculate the number o + bzi6ze2wfe0f 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 mawzdvw zsmjem * 2+p:3r1z39rany molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (-vcs*luk61m i7i v +rzfa )8gja) 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 c0mby:n jj+xb ke.h -45.1$ \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 vd.:w t q 2mjurs.fl*9a5b wk7breath you inhale that were also in the last breath Galileo took. [Hint: Assume the atmosphere is about 10 km high and of co:w jb 5qvrk.2tmw9*.fd s7 alunstant density.]   $\frac{molecules}{breath}$

  (a) What is the average transl6( rnrrgou0 5fational kinetic energy of an oxygen molecule at STP? 6fonurg(5 r0r   $ \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 atomscz)j l k 1mmh4:h)-vui near the surface of the Sun at a temperaturelzcv ) ujm1mh hk:)-i4 of about 6000 K.    m/s

  By what factor will the rms speed pdp; h5tl+92.wzjh9 w- ofwhvof gas molecules increase if the temperature is in5;pfv+2 -thhwowzd9pjl w.h9 creased 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, ;nzs ( -k2tqcdf/o :ckjk1l.t0, 4, 1, 8, 5, 3, 7, and 8. Calculat:nks d2o l-ck1c/(.t;ftqzjk e the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules iq 8e:ap /9n.v.-khe +hgwdqign 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 v;xnlw4 o z s68ew:x9srolume is held constant, by what fr xew z nws4xl6;s:9o8actor does $v_{rms}$ change?   

Show that the rms sp y98ks dlfbf0wf2tl*5 eed 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 ratdb kz- *t bj(r hns t8vd/,ev;5ob25laio of their rms speeds is equal to the inverse r dsr8z5bb-ahv2k tltd ,o ;vb*jne5(/ atio of the square roots of their molecular masses.

  What is the rms spee k bx4ixz 049f.mk3bwvd of nitrogen molecules 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 oca2so/p; nt.7u6h y ean oxygen molecule at 0 $^{\circ} $ C    m/s
(b) determine how many times per second it would move back and forth across a 7.0-m-long room on the average, assuming it made very few collisions with other molecules.    round trips per sec

  What is the average distance between nitrogen moleculeszpjc v5 j6d3j)zfvqz+h: iy:, at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed oxr2qi i7rh v 2zwt )mhy2ig192f an amino acid whose molecular mass is 89 u in a living cellqh2ir72vm)2xrt21y i9h zwig at 37 $^{\circ} $ C.    m/s
(b) What would be the rms speed of a protein of molecular mass 50,000 u at 37 $^{\circ} $ C?    m/s

Show that the pressure P of a gasm, 3cb7 q:jmyf 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 uraniuoa+0b 6s2jazbm, $^{235}$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 pha/ jo bvoivguo, 8;-. jj+dz 61bdin/pwses 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 t (;h;i mdc jzbp:+ba7the pressure is 0.01 atm and the temperature is (a) 90 pabtj:;i ;+7h(bcdm z$^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humi hy. )tud.du0zc s,0jp xu:l87ggz zj7dity is 50% on a day when the temperature is 25 07t xh:j.8zp) gu 0d,j7zuyzsldc.gu $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressur. c kww0xrk6i8jb+1 txxo7aa(e at a place where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mou mocob 0lss:p 2e3, n.pi;xc)se4c f)vntains is 0.72 atm, estimate the temperature at which wate,l :sv4s;socepf)20p. c n )3mecibxor boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of water is 530 Pax9yc6dmwf9 q 0,xo2 le and the relat0x6e2,loym9fcxq9 dw ive humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water odb cxv: hg,r(if 9ykv *u9v6m8n a day when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure 7m o3pgb3mb 4jf93wxbinside a pressure cooker if the water is boiling at a tempe3 bw 7 m3m94opbxjf3bgrature 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 vo7 x ;wgsth*-wklume 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 ofghnlt 4,e l5.a 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 molecugorb4j6f2hs 0 ;lhi*fle (see Table 13–4) to diffuse a dist6hfgoblfr ;0s i*j4 2hance of 15 $\mu m$ in water at 20$^{\circ} $ C if its concentration varies over that distance from 1 mol/$m^3$ to 0.4 mol/$m^3$ Compare this “speed” to its rms (thermal) speed. The molecular mass of glycine is about 75 u. t $\approx$    s ([color=rgba(0, 0, 0, 0.85)]Round to one decimal places) $v_{diffuse}$    $ \times10^{ -5}$ m/s
$v_{rms}$    m/s

  Oxygen diffuses from thbo7xo,x6tk )h)b k26 kz8z hfue surface of insects to the interior through tiny tubes called tracheae. An averaxbo,hz kf) 2hxzo8 bk 67k)tu6ge 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 ha)deowz69g po- :bax +vs 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 bee7trp,3t o c:uzujnek2g pg20*n 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 tempera j4hqz t8(pn u36x5lpzture. How much error will be made in a recipe calling for 300 mLh6pqnzux tj(p 8z53l4 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. xpe0,0lz w mcyph; kt9d6. d-;t pbo2iAfter many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of tmp0l ikyd p2;h tt;pwz.d-c9 b6,o0ex he original gas remains in the cylinder?   

  Estimate the number of air molecules in a room mh739 yzu*0vytt(cg6wxy md 3of length 6.5 m, width 3.1 m, and height 2.5 m. Assume the temperature is tuhgm3*(yvxc9t zy0ym 7 63wd 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the dene.(;mfvzp 6j2*gwa ml sity of matter 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 0ssc edpv/t;6 ar )i/yvacuum techniques is about/ )vtd /ic;pe0 ya6srs $10^{-12} N/m^2$ At such a pressure, how many molecules are there per $cm^3$ at 0$^{\circ} $C?    $\frac{molecules}{cm^3}$

  If a scuba diver fills his lungs to full capacity of 5.5 L when 10 m beld vj5-, r6.x,;cvij 1ce pyodeow the surface, to what jie 65; 1veod,- rc.xdcvy,pj 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 atmosyywh3g(dwbq kl +2,ltzh+ 32jphere at a speed of about 40,000 km/h Mol 23 zyhwlk +h23jyqgwt+ d(lb,ecules (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 any sh2,l )b v/;(i yloc4+djvtq ideal gas 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 volumeo v*h4hrwn *h3r6bc7i -n 9pqa 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 of atmosphe 54b f9ltp*cadzu ./ziric pressure at the surface of the Earth, estimate the total number of air mold uf9c45li /azp. *tbzecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contayo4ic0nmp4 1tgixs2+1zr x,cined 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 = 2000 pzam k/j:y gm5 +j4c0rb:z4)ibr8uaa gsi (13,800 kPa) and at T = 259K How long will the cylinder las4ymumbj +k:):gjraiza0 czgb8a r45 /t if the flow rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a ul* k-uh a7q8xbowl 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 gasoline2 d8su i0n;geo 2l)+vh1ewkue 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’s equator at 2hqrau tb8,z325$^{\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 glass15ai antc x2j d1sz 2n+ljiq72 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, r4:72zejwq7tkq0 +snwxvh o*o.w7z r 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 fullyvl9*3umg (z7cflo:c i charged, 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 t *prf9k.0zucf)gq -btr+ z j8the Earth is $ 1.12\times10^{4 } m/s$ so a gas molecule travelling away from Earth near the outer boundary of the Earth’s atmosphere would, at this speed, be able to escape from the Earth’s gravitational field. At what temperature is the average speed of
(a) oxygen molecules,    $ \times10^{5 }$K
(b) helium atoms equal to $ 1.12\times10^{4 } m/s$    $ \times10^{4}$K
(c) Can you see why our atmosphere contains oxygen but not helium?

  A 1.0-kg trash-can lid is suspended against gravity by tennis balls thrown c.t,cmfc. ygom:y)7 hczdy y7j t:f-9vertically upward a m f.: cdzgt7yj .c:cf)y y-om7,ycth9t it. How many tennis balls per second must rebound from the lid elastically, assuming they have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter +/wmzwjjzdb09i ,i0 8vl6h ou(spherical) bubble of air from a depth of 14.0 m in a lake.9+w8i,vd huzzjob/wil6jm 00 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 surface?    cm

  Calculate the total water vapor pressure in the air on the fo/y.y- on) f2wvsug+svllowing two days: y su-ygws . vf+v2n)/o
(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 in1:83as mz7pei+uk8j no2 zjprf 6b*lw the density of iron at STP, and when it is a solid deep in the Earth where the temperature is 200izo uk+z3jbs*w61:n mjp87r 2e8pfa l 0$^{\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 con-- j+:apduqcc* 1yqyastant pressure, the coefficient of volume exyjcq pqu-: ad1yc -*+apansion is equal to $\beta$ = 1/T where T is the temperature in kelvins. Compare to Table 13–1 for gases at T = 293K (b) Show that the bulk modulus (Section 9–5) for an ideal gas held at constant temperature is B = P where P is the pressure.

  In humid climates, people constantly dehumidify their cell v ;:q zoqu,3lkm5kc1duk8v )dars to prevent rot and mildew. If the cellar in a house8) u:1 mk,vkqkdo5zdlc q;u3v (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