Which has more atoms: 1 kg of iron or 1 kg of aluminum? /0nr6s k7eifq,y ye9/ hlrdd6 See the periodic table or Ad e/9r y6/ekq yl7hrfi0,6sndppendix B.

Name several propertie aru.4lb3;bem+1kcvg2xz wqj18mr2 ei: 5 ngzs of materials that could be exploited to make a thermometer biz:l v1eemcunk4.+2xga1rz5 b; 8m2qr gjw3.

Which is larger, 1 C py z3(m)2uhvpfb 7gvm;akz( 7$^{\circ} $ or 1 F $^{\circ} $?

If system A is in therma 79nx:gst 3ipll equilibrium with system B, but B is not in thermal equilibrium with system C, what can yg9i7: 3n xlstpou say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to ah1l )gm) on0tx/g15zlpf1 w-3tphfew strip of iron. When heated, the strip wilwg thgzwhp1l/03x5m) to f)e 1nl1-p fl 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 coefficie9 wakq f/zo0fr*en4 pp*/ku*unt 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(j h6ic oju4v- control a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch is a glass vessel 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 temperat 4-o6(jchiuvj ures.

Long steam pipes that are fixed at the end .f*r/u 7ourqjs often have a section in the shape of a U. Wrufr*7.qj /uo hy?

A flat, uniform cylinder of lead floats in mercury aa 5j;c2bvd ,prycm9e;ee+vg: t 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass y ;e eut4 d39wp*;nnvythermometer is first placed in a hot tub of water, the mercury init9d ptuwn n;ey3v4y*;eially descends a bit and then rises. Explain.

A glass container may break if one part of it is heated or coo fjt2-v4v +vlkled more rapidly than adjacjl +kv2vtf -v4ent parts. Explain.

The principal virtue of Pyrex glass is that its coefficient of linear expansion r1fq.lrt1g o0is mucr.0 golf1t 1rqh smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clj:, ptbhrv m07,o.jguik fm ad;x9 (b-ock, 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 +34gv /8dczv bra8:kvarj n/bbulge so badly the can will not stand up. What h avnzja :v3+vb kd/8r/rc4b8 gas happened?

When a gas is rapidly c7f u 2 6qa ybnye;rac0,qj9v1f6hqe v.ompressed (say, by pushing 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 what happens to the momentum of molecules when they strike the moving1af rjeqn he6v2av0. ,y 96c;y7 qufbq piston.

Will the buoyant force on an aluminum sphere submerged in ug3k -f.d )dkf6j nw-2n+tcxhwater increase or decrease if the temperature is in+3) 2chfu6kdt -knj fgxdnw- .creased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Cm(sx*vd+ o 7nzjf5 g-mharles’s law follows from kinetic theory and the relation between average kinetic energm7n5xf+ *oj zgsd m-v(y and the absolute temperature.

Explain in words how Gay-Lussac’s , livl-g2vod 06wksu7 law follows from kinetic theory.

As you go higher in the Earth’s atmosphere,udl kym50wr* taa.h8; 8e yq88vbvf b2 the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth re n kqni4yel //+8 g iueb+ yth515zgez1e:i0yofers to the minimum speed an object must have to leave the Earth and never return. The escape velocity for the Moon is about one-fifth what it is for the Earth due to the Moon’s smaller mass. Explain why the Moon has p0g l4t/q gynueyzi i k +hieo:58zn b5/1+e1yeractically no atmosphere.

Alcohol evaporates more quickly than water at r5rdwzv+veq / yv; :i2loom temperature. What can you infer about the molecular /5vi:dev zlr2;v+yq w properties of one relative to the other?

Explain why a hot humid day is far more uncomforqs 0deyjuqc 1 d5g*c17table than a hot dry day at the same yq *udcsd5e c1 07qj1gtemperature.

Is it possible to boil watep )ytgvy )ey8e fkbp q2jr746:r at room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the h39y6wg2i r8m3dli8( jqu4 qjtwm dzw8umidity is different. Which is more dense, the dry air or the humijw qt 6j3ugw4q3 yidz8 2md8l 8r9m(iwd air at the same T? Explain.

Explain why it is dangerous to open the radiator cap of an oix2 *5ua f5xxpat: 9t:dljv c0verheated automobile en:djvai95 2 tp x0x:ftlx *au5cgine.

Why does exhaled air appear as a little whit6+6 smiqwx,s id)q(kq e cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram copper pro)h;(9wm- iv) o kyrvenny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold rir 8xgau0 , 1k3gj6ngk. vs/dring compare to the number in a silver ring of the same sa igxk6kj.3/vrd n1g r0g8 ,umass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken td10a+ f6mn ejcm*v3*u.d jxujo be 68°F. What is this on the Celsius scale? 6 0dx*j+jcma*uedu13jv n.mf   $^{\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 lo uuigf.yknfme7 *5-y;west 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 thermometer, the alcoho 3gys0edn/rb 9( aubg5l column has length 11.82 cm at 0.0n/e3ys( 9gabub g5 rd0 $^{\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 lol)z8gy m kw0 qtv/r9r.3iff 8qng (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 300 m tall.- kncfpe :/x( itzq2;b Estimate how much its height changes between July (average temperature of 25°C) and January:ec2ib/qp(- kx ;tfnz (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 t8aed98w:c f4(od 7mrfu-kvdshe rivet hole are often used and the rivet is cooled (usually in dry ice) before it is placed in the hole. A steel rivet 1.871 cm in diameter is to be placed in a hole 1.869s4 dafm7w:( f-d8k r9ecuv8do 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 4 b v u(5puvqn *)yja7a8$^{\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 vo l80lu8su2e *h3ynq tjlume if it is hel *t8y0eqnl 2j3 s8uuhated 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 water at ,t4 j snyn -;hv:9atsq100.0$^{\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 /dmk9fl 2i8 5fopl9 ez55.50 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 riny3 omwvx.f0wt2m+cy7 g 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.lhv4,yo7ob1 o mrw t9 in a long, narrow vessel so it can expand in essentially one direction only, show that the effective coefficient of linear expansion is approximately equal to the coefficient of vtm,o 49 .7vy1oowlbrholume expansion $\beta$.

(a) Show that the change in t-cmhvl0,w) de* ws -2ue8 (jj+jrme plhe density $\rho$ 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 lin9 *aiii ht.dg / 5plb.u63ismmear expaigmip5.ut mibi.d 3ls/9h*6 a nsion $\alpha$ 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 sooxxe8oo0 e c19lid, $\beta$ = 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: 0yfn uw0awb/ is made of brass and keeps perfect time at 17 0wb:0aw /uny f$^{\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 diameter of 0.1z5t-i 6 +c0xxi 5ig*i+rjcut n40 mm. The bulb has a volume of 0.g i5uzjint+irxc0-6i+tx *c5255 $cm^3$ 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 abou fiflp5:d001p3n ex dit its axle on frictionless bearings with angule0 :xpipld3in15d0 f far 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 length when at 15°C.51 z iz2ced,v)zj,dj(-b kkbn How much stress is required to keep it at this le1vckzjk , dbzj 52n e(,zd)-bingth if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-sectional .ogbqav ,f oz5t -(3n4 mpds2yarea 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 2 axs0+qrz2bp-/ 5f; 2whxtdzb 0$^{\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 thx ja.* yk5ubh tp9-xj4e Kelvin scale:
(a) 86$^{\circ} $ C,    K
(b) 78$^{\circ} $F,    K
(c) -100$^{\circ} $C    K
(d) 5500°C,    K
(e) -459$^{\circ} $F    K

  Absolute zero is what temperature on the Fahrenheit scalbomh,g;aj-ir )- 7)jobn2y pg e?    $^{\circ} $ F

  Typical temperatures inoxmze *cx )jte)-4m*q.vs7 9xs 3krdx 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 temperatur, l mbqgkim;+7e of about 2 ,igk+blmm q7;0$^{\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 zz ;btw dvuwl;i5m rpn;x,395 using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of nitrogkd4n5btz paczeeia9- :y c35nf w:35fen ($N_2$) 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 con)i c,). 2jlc pk nnm0qy+hp.eftains 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 gas is at-a: lwol dnn,b7w(bx0 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 k4:2op3x( zg, gsnxg uag of argon gas at 384x p,ga go(z2: g3unxs5 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg ofncgpq5;n+ / ui $O_2$ 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 in1sz u+-,j )+gw wwpbsiside the balloon, which makes it less dense than the air outside. Suppose thewzbuw ++i )1, swsp-jg 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 aw8 voe 3utf a cp5i6p)kp9*7fat 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 187q7mjsx* zoc ec*. n*z.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 sea lebzc-rxvm -7,a 8vh28w img*bvvel 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 mol .jcv. +ci5kclqk-w /becules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? Howo: 3elvq *15rlv ktg.e many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) molesw 9wbwph,y*ntnd1 0j,,    $ \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.)anejq d qg; 7x6*kc,p1$ \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 iofyym lk ,i:+ama w/cz7-+;xw n each 2.0-L breath you inhale that were also in the last breath Galileo took. [Hint: Assume the atmosphere/:wzowyx +,cmlyik; f7a +a-m is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of an fma71bwp9z+: x uz6r6,8h bw yn(gquuoxygen molecule at STPh7ubg(rm8z1by669:znf u + qu,wpw xa ?    $ \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 spee+jp) qbg;bse5s/r 4 dkw8mds+ d of helium atoms near the surface of the Sun at a temperature of ab+)qgr /j pw eb+8k 5b4sdsms;dout 6000 K.    m/s

  By what factor will the rms speed of gas molecules i:1/4,t y ktpayu+acnazj*e7encrease if the temperature is increased from 0 4e+a t1c anyky7*/tj ,zeupa: $^{\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 hav1,o vtgag x6dc)lm4u3w j7ql-e the following speeds, given in units of km/s: 6, 2, 4, 6, wlt)l gg3 od6q ajx7v,c4m-1u0, 4, 1, 8, 5, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at x)v 7b:eazrt420.0 $^{\circ} $ C is to be increased by 1.0%. To what temperature must it be raised?    $^{\circ} $ C

  If the pressure of a gas issp:bd fmoe5iw1f011kk 1bt e/ doubled while its volume is held constant, by what factok 1e:ot0 1b1se d1p5kwm i/ffbr does $v_{rms}$ change?   

Show that the rms speed of molecu9 )lw)hffg) nzshxa0.les 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 /k 88ofvi ujy7ykp6e 6at the same temperature, the ratio of their rms speeds is equal to the inverse ratio of the square 7vuf8ei jk8/py6k6yo roots of their molecular masses.

  What is the rms speed of nitrogen molem p8 3n;,1o7kt nrpzyicules 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 spy+vvcr9+f n( reed of an oxygen molecule at 0 $^{\circ} $ C    m/s
(b) determine how many times per second it would move back and forth across a 7.0-m-long room on the average, assuming it made very few collisions with other molecules.    round trips per sec

  What is the average distance between nitrogenqq;5,sux r+jz6ut/ lh molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular mass is. of cw0 2w,+tbap)rya 89 u in a living t. fab yap +cwrow),20cell at 37 $^{\circ} $ C.    m/s
(b) What would be the rms speed of a protein of molecular mass 50,000 u at 37 $^{\circ} $ C?    m/s

Show that the pressure P of a gas can be writtenu*r6k2,. ftiu t50goaucqrm 1 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 urapt +be )2to,vqnium, $^{235}$U and $^{238}$U (the superscripts refer to their atomic mass), can be separated by a gas-diffusion process by combining them with fluorine to make the gaseous compound UF$_6$ Calculate the ratio of the rms speeds of these molecules for the two isotopes, at constant T.   

(a) At atmospheric pressure, in what phases canlk1zzs (8wr*hhms :o; $CO_2$ 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 temperature:/-v)be3frtb 3u) bli(v twpw is (a) 90vftb( - ew3vbb/3tuwp r):il) $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity b23o qrc8cdi 8vaa1(tis 50% on a day when the temperatb8ict83 v (ad2arqo1cure is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water boils u881rs eifbc 5/i/rts at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in thebb6vtzcq9,c a : xajap55*05zjt i f9s mountains is 0.72 atm, estimate the temperature at qxz6v :scij9 a59at5*ab5czfj bpt0, which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperaturea f60wmy2/ ht2i 2jiil on a day when the partial pressure of water is 530 Pa and the relatia i2jfwmi /l62it20yhve humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day wf+vuz)q* gy7ghen the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cooker if the water is bmsj++ 3u+;7ux 2u)a xyyhomrhozz89ioiling at a teiymr;9uuj+z +u7z+ )oo3sxa82 mx h yhmperature 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 volume 6lx-x2f/3p jpb80$m^3$ at 25 $^{\circ} $ C is 80%, what mass of water can still evaporate from an open pan?    kg

  Air that is at its dew 4zs px(e5iv3iukf0n 7point 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 neededu:qnn7 7todrp (n-*juoev7h2 for a glycine molecule (see Table 13–4) to diffuse a distance of 1 dhuqe: 7jo pon-2n7vr7 *t(un5 $\mu m$ 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 a3- o3+9cthyriysf n 9the interior through tiny tubes called tracheae. An average trachea is ab-fcry 93sihyo3a t +n9out 2 mm long and has cross-sectional area of $ 2\times10^{-9 } m^2$ Assuming the concentration of oxygen inside is half what it is outside in the atmosphere,
(a) show that the concentration of oxygen in the air (assume 21% is oxygen) at 20$^{\circ} $ C is about 8.7 mol/$m^3$ then $\approx$    mol/$m^3$(Round to one decimal places)
(b) calculate the diffusion rate J,    $ \times10^{-11 }$ mol/s
(c) estimate the average time for a molecule to diffuse in. Assume the diffusion constant is $ 1\times10^{-5 } m^2/s$    s

  A precise steel tape measure has been calibrated at 20v3va(8f a/;vn 6 7t l9kr dpuak:yk8vw$^{\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 measureq-s uj tuy 8e;b1lev-u8u+5hdh.2e ot has 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 Pyrex measuring cup was calibrated at normpzi(yrw2iur, xn9i*. al room temperature. How much error will be made in a recipe cizn 2yruriw(9xi.*,palling for 300 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 mas g y*00scv:4 j4p:tieex 2mqany balloons have been blown up, the gauge pressure has decreased to 5 atm. What fract 40evamx:ti j:s*sp4cqge02y ion of the original gas remains in the cylinder?   

  Estimate the number of air moleca q g r6,x:b8 6pu5*dhi19iga-w(ka4ukabweeules in a room of length 6.5 m, width 3.1 m, and height 2.5 m. Ass (duaui 6i-6kwap hx54 a9grg8 q:,ea1wb ebk*ume 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 one ,qp;;4pv 6xzbzp6u(/t p f sqxatom 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 availabl/3wa8rd ng1no f*wr 9be vacuum techniques is about rnowg a nw81/fdr9 b3*$10^{-12} N/m^2$ 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.,r0)inf- gkks 5 L when 10 m below the surface-)fr gnkk s0i,, to what volume would his lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmosphere nkfl 4dyul6 m-81x9yh 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? yn- 68duyxlfhmk l419(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 idealzebblr) 0umr45hgla9wmd - 1h3iy 4i3 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 volume ofuaroiikbil5su- r8. 9/ d/gf( 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 pressure at the surface of the Earth,:,/vibge8vxtid x, 0 h estimae/0:8,vvxbtdiih g, xte the total number of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules tmw,,5/sqq 8(ql)q exqf6he p +pwud3contained 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 ig 1(1ke7oftf xn a hospital has gauge pressure = 2000 psi (13,800 kPa) and at T =g7f1 f ektx(1o 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liquid mercury at 01. 3;w az-ww(hn lddqi$^{\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 7wuy9a1cl5y j 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 arouo3 dk6/syrb g1aspk) 4nd 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 tionk-(2 h)dam 5tu*(gibs+sw e ghtly onto a glass jar at 20$^{\circ} $C. To help open the jar, it can be placed into a bath of hot water. After this treatment, the temperatures of the lid and the jar are both 60$^{\circ} $C. The inside diameter of the lid is 8.0 cm at 20$^{\circ} $C. Find the size of the gap (difference in radius) that develops by this procedure.    cm

  The first length standard, adopted in then ue 3b9xjo7j j:iz(:i 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 9w ys5:f:nv liqx2ep/at 20$^{\circ} $C. The volume of the tank is 11.3 L.
(a) What would the volume of the air be at 1.00 atm and at the same temperature?    L
(b) Before entering the water, a person consumes 2.0 L of air in each breath, and breathes 12 times a minute. At this rate, how long would the tank last?    min
(c) At a depth of 20.0 m of sea water and temperature of 10$^{\circ} $C, how long would the same tank last assuming the breathing rate does not change?    min

  The escape speed from the Earth is jzq yxlhoo c3z :9co 9xe)os8q l0q7v.*6m hh:$ 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 ten-.j5 0/xto emrl 9ak+e9uwqmp9 c*zmqnis balls thrown vertically upward at it. How many tennis balls per second mus t9 m9 pm9w+qq z-j/cmruox.l0eea5*kt 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-diametepkowo- cp, 4u5r (spherical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature is consta,cu4pwpoo -k5nt 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 following two days:ys - iqq**ro.jxnr*m 2 yjs*in*oqmx .*rr - 2q
(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,o7+ d3 wopsaw, and when it is a solid deep in the Earth where the temperature , w s7p3woado+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 l;y lq.dfbhwcs(.) a6p aw to show that, for an ideal gas at constant pressure, the coefficient qfy6 hds.ac(bw.)pl;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.