Which has more atoms: 1 kg of iron or 1 kq3j 3e) ybtr2ig of aluminum? See the periodic table or Appendix B.br3i3 ty 2qj)e

Name several properties of materials that could be exploited to make a thermomet6:j/mca n tc/ier.t//6ja c nm:ci

Which is larger, 1 C +ie*a5gy bjouy6l4g e p*mby7k u;8p/ $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B is not in5 igd3z7 kdg awzu(m(h. ,(pfm thermal equilibrium with system C, what can you say about the temperatures idgmk zp75((,a3gwzud.m ( hfof A, B, and C?

A flat bimetallic strip consists of aluminum riveted to jxq6ma,ma( o. a strip of iron. When heated, the strip will bend. Which metal will be on the outside of the curve? [H(aaj.6q, ommxint: 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 coefficiepd;9 m+gz5 +nhh v.e ymph)y6rnt 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 thwhvyqxi:(sxy :/ucuilumv++10 m a-3 vj,l f0 ermostat used to control a furnace (or other heating or cooling system). The bimetallic strip consist 1:v-wfs:h l,ayl3uqvu0vc+0m+x jmi u(/xi ys of two strips of different metals bonded together. The electric switch is a glass vessel containing liquid mercury that conducts electricity when it can flow to touch both contact wires. Explain how this device controls the furnace and how it can be set at different temperatures.

Long steam pipes that are fixed at the ends often have a section ig6y(5st oj5 yen the shape of a Uo6gtjy 5yes( 5. Why?

A flat, uniform cylinomys3ta08yr- y+.j 2qco bg1rder of lead floats in mercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glac 2hpn2 a9xj+iss thermometer is first placed in a hot tub of water, the mercury initially descex2 an+2ich 9pjnds a bit and then rises. Explain.

A glass container may break if one partxn(4u2i:e bnf-lerk 6 of it is heated or cooled more rapidly than adjacent parts. Exnn6e u2( fxklr4e-:biplain.

The principal virtue of Pyrex glass is that its coefficient of linear expansiou tk: 8ekhu-f2n is much smaller than that for ordinary glass (Table 13–teu2 k-u8:fhk 1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurate at 2sv2l+y)jo+v tqts-hp0ox ;(t 0 $^{\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 5/f wfs*vfroj bf/ j kgn*d2tz)3t6ka1/xoo 2will cause its bottom and top to bulge so badly the can will not stan)*2/2foxfoo*j f a/ sk5gt bfrw31tdj n6/zkvd up. What has happened?

When a gas is rapidlybdw6 w08j5zh0v3aqr w9ydj z / compressed (say, by pushing down a piston), its temperature increases. When a gas expands agay8dwa/ 5vj6 zjr0hw9dq3w0 bzinst a piston, it cools. Explain these changes in temperature using the kinetic theory, in particular noting what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force on an aluminum sphere su0( qv;+kfyv5ao lfw9 abmerged in water increase or decrease if the temperature is increased fr9f+v (5flvy ;aw aqo0kom 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows fr7ozykvz5i1)5f t+, o2.anhd + 8fkwash7ewekom kinetic theory and the relation between average kinetic energy and the absolue 1f5w +oih7kyk)w, +s 8f.7dozhvt a52ze knate temperature.

Explain in words how Gay-Lussac’s law follows sxnivg5o 3d+d:p2nh 9 from kinetic theory.

As you go higher in the Earth’f k6zry:hluj/ q48;ao s atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers torvd l963c kxqsm l3su(aiu 42c-x6ao. the minimum speed an object must have to leave thev66q mx allkrx 2udcc si34uso-3a .(9 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 practically no atmosphere.

Alcohol evaporates more quickly than water at room temperature. What can you 5yx99l :/rea*g q6;mfwuyjqe infer about the molecular l e/a* u;yfg5e:qxwmrq9y69j properties of one relative to the other?

Explain why a hot humid day is far more uncomfortdi0u hq c71im2 jqykju 7y.(ey.krc87able than a hot dry day at the same tej k.0qu7y7q7c je hc1i mdky.y(8ur i2mperature.

Is it possible to boil water at room temp3awxay*9gc zk -cau9ejp, 1c1 erature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when t4bmlk6gpc0 ztx-tm d0jbg 855he air temperature is the same but the humidity is different. Which is more dense, the dry aiz 06x5 t08 pt4g5lm k-gdjbcbmr or the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap of an overheated adw -tvn: x8o-toatpgb/b 0;h, utomobilep/;,-bh avgb:0dtt- 8tnow xo engine.

Why does exhaled air appear as a little wdir dl iy *s5xjs.dco xe9w.*4x)f0+bhite cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gramgn sk4a;6afu:i 4bjl 4 copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare to the number in0 0inbswtb, b8 a silver ring of 8i btbsn0w0,b the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°7 nn(7.z uu u 8j1c)sqy/fccshF. What is this on the Celsius scale?n7cc1/nzuu uqf8 sh)7s y.(c j   $^{\circ} $ C
(b) The temperature of the filament in a lightbulb is about 1800 $^{\circ} $ C. What is this on the Fahrenheit scale?    $^{\circ} $ F

  Among the highest and lowest temperatzoza )w.ob 1u5doc/do4lth+ .go*d 9b ures 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-glasspwi1/ts:b4 zae:a ay,0j 73pkys:qf; 7 aziha thermometer, the alcohol column has length 11.82 cm at 0.0 sw3b:akai ;77 /y a:4 yz:,1p taihp0sajeqzf$^{\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 rk-r/rhet7o2 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 wrox0:r.av x x5wux8,bksught iron approximately 300 m tall. Estimate how much its height changes between July (average temperature of 25°C) and January (xbwau 5k8 x0xv s,x:.raverage 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 hoae09.t /y-c0o qt gooj6bli*; dao 6ujle 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 iogtocjoti ja 0 9*0u ley/b. ;-6oaq6ds 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 at9w; w-wj+ esy h +;d9pc;nngoj 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 innb6go mdsr98 x (7;jx6 4abtsc volume if it is heatx8xg7ran;sd 69b 4(c6 mo sjtbed from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brimpc lx /ap:nzw s,e1,irq+xfo6 , yi+1r 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 watermf or10 uao:/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 made of i/ d 3uy3vxtl9sron. 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,ai/m3f tetp f .2a9v7l narrow vessel so it can expand in essentially one direction only, show that the effective coefficient of linear expansion is approximately equal to the coeffic fie /ta7tav 23lm.9pfient of volume expansion $\beta$.

(a) Show that the chan4bcfhx 5 p6gb5ge in the 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 linear nul ;/v)/eoy -0 zmmfwexpansion m nvwle/o )zmuy-0/;f $\alpha$ 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 isotropic6.pskwm.4sxav e 9dj1 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 clock is made of brass and keeps perfect tij6co ezn:x e,qk(2)0zh*sf btq) o- vime at 1z 6hq-eb2oz feq )tx 0io*n(kvs)j: c,7 $^{\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 i7;4+fgvz eg(oki pkw ;nside diameter of 0.140 mm. The bulb has a volum7+fg(i pkg;4 ;ozkew ve of 0.255 $cm^3$ How far will the thread of mercury move when the temperature changes from 11.5 $^{\circ} $ C to 33.0 $^{\circ} $ C? Take into account expansion of the Pyrex glass.    cm(b) Determine a formula for the length of the mercury column in terms of relevant variables. Ignore tube volume compared to bulb volume.

  A 23.4-kg solid aluminum cylindrical wheex d)2vz8gck:xl of radius 0.41 m is rotating about its axle on frictionless bearings with angular v)g dk:x cz2x8velocity $\omega$ = 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 lenhzi9p cnhy ,vr8a 6;k x,;7gkxgth when at 15°C. How much stress is required to keep it at this lengt a9chny,,;i kxpzv8;h r6gxk7h if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of crosskrfm wr/;n-.3 8new pd-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 13y4;h /lflbpm c 98u.g/q, yklh4.122 cm at 20$^{\circ} $ C is to be enclosed by an iron band. The circular band has an inside diameter of 134.110 cm at 20$^{\circ} $ C. It is 7.4 cm wide and 0.65 cm thick.
(a) To what temperature must the band be heated so that it will fit over the barrel? $\approx$   $^{\circ} $ C(Round to the nearest integer)
(b) What will be the tension in the band when it cools to 20$^{\circ} $ C?    N

  What are the following5il7o +bxv hc1wmqq 12;w8kik temperatures on the 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 wha. ze,yzh(aq9c3 vha d0u0h5drt temperature on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the ig txe9j; *n) :mh,gbzz:n;ylqnterior 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, t:kqtv6my+ atksse6.2zq j3 3air at atmospheric pressure and a temperature of . t3q 2tssytj e+kzqa:6vm6k3about 20$^{\circ} $C is compressed in the cylinder by a piston to $\frac{1}{9}$ of its original volume (compression ratio = 9.0). Estimate the temperature of the compressed air, assuming the pressure reaches 40 atm.    $^{\circ} $ C

  Calculate the density of oxygen at STP using the ideal gaslswlr:w (hv 55 law.    kg/$m^3$

  A storage tank contains 21.6 kg odqq7pfc 8;;c ow:.f9pq0 xd wdf 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 contains 18.5 kg ofuv3bmh-v1: d ueza8vj 3msc1* 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 i-5- ocd;f1sg21bwh sqvl.uwvn5q e)1imya s4s 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 holw,cb;xfld;3o ding 105.0 kg of argon gas at 385;fl3d ,;owb xc K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg o0 k fgb 0jsxdro tvj8+1o1) gc;5xi.dif $O_2$ 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 ho)6i 8 tfrc;tdeating the air inside the balloon, which makes it less dense than the air outside. Suppose the volume oiodtc8tf; 6 )rf 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 *kh*+f s g-0jtzn pbe/2kk ,pi6 )txunat 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/ hv zz x189i/v:k:lwcs)jwfp.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 level and 20.0fe *iz s+w8 brtt;*t yxv.9fc*eut*4 l $^{\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 z 1taut9yoi3(:v pok3 a.. uomof molecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How many molecp8 ebi p;at-2lules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) u x.-r3+zlnft 7(pbxnmoles,    $ \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 uv2z*f;fh;jc,,bgw n5.1$ \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 eaqwk i/fk5x4 ;ech 2.0-L breath you inhale that were also in the last breath Galileo took. [Hint: Assum4fei/kq5; xkwe the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average2dak0 e-g.xf md7ko-gli;vo bbd6w*b +m,2uq translational kinetic energy of an oxygen molecule at STP?l b7o-ddgw2-ob mv+i0,2 dm aq ue;.gxfk6* kb    $ \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 he/tn8q)s (aoy tpj(*: ub,jrmtlium atoms near the surface of the Sun at a temperature of about 6by:am rj/ )pq*uj8n(o stt(,t000 K.    m/s

  By what factor will the rms yo4+rmy ;6pcy fd4hy -speed of gas molecules increase if the temperature iy y4dhfy+rp6o; myc-4 s increased 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 followibmiyo 67a:31e,cym qing speeds, given in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and ac73be yi 6i1:qymm, o8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas hkspmls1ac ,lm+k ecg: (6r)7 at 20.0 $^{\circ} $ C is to be increased by 1.0%. To what temperature must it be raised?    $^{\circ} $ C

  If the pressure of a gas is doubled while its volume is hftbbgnw9cp0 35 / rg3weld constant, by what factor doe03tf5pn bg 9cgwwb/r3s $v_{rms}$ change?   

Show that the rms speed onwv u 9l 250mtb9gsxg/f 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 templ tcu ng.ja.n9+(2qj kerature, the ratio of their rms speeds is equal to the inverse ratio of the squarenj( + atkgq2nc9.u j.l roots of their molecular masses.

  What is the rms speed of nitrogen molecules contain e: zo2wb3-yxvz nl,n4ed 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 molermwmc 5mh)2wky;. u*s cule 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 molecules at ST765 xwc 2im 6*w-ftf8xp5cpb;xdog fz P?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular mass is 89 agzf(ap7tz8*u0a na(7o my9 e u in a living c7ap0(*t y7aaef(mazu z8ng9 oell 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 ns6 p k5-7wldmof a gas 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 uraqt92n8 /n/bwwz ( wir:g *jqnlnium, $^{235}$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 pwdgv4 d)z9 l4b .yctb4hases 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 8 bam)p7dnl8ym 7qd8f is 0.01 atm and the temperature is (a) 8adyd78mfpn7mbq) l 8 90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately-7h/9nsguc0k9l0vpd:cz9mmg hw *:r eoi )qa ) if the humidity is 50% on a day when the temperate)u:rc/ nwd7g9k-m 9m 0os g*plcqhiz9h0:va ure is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place w:p/ 0mo)yi m0ee;uovm5qs2 y hhere water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in d4 aq3c 8317esthai (ind, uufp2.z fvthe mountains is 0.72 atm, estimate the temperature at which watc ua aqd 3zpi78n 2(hduf.4vs3e1fi,ter boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the ;m w nc ib(904ojpna4oim; 6vppartial pressure of water is 530 Pa and the relative humidity isoj4(p i4b ; wmpno6m0in;c9av 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pri706gxbk8 ;ml xtk,gressure of water on a day when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximi c85 n9eb5hfb0sfo9d ate pressure inside a pressure cooker if the water is boiling at a temp bio9dhn5b c5fs90f8 eerature of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a r6p;jl4c cnzo/* h-ejxoom of volume 680$m^3$ at 25 $^{\circ} $ C is 80%, what mass of water can still evaporate from an open pan?    kg

  Air that is at its dew porv8cwxkyfyd/(. b )e: int of 5 $^{\circ} $ C is drawn into a building where it is heated to 25. What will be the relative humidity at this temperature? Assume constant pressure of 1.0 atm. Take into account the expansion of the air.    %

  Estimate the time needed for a glycine molecule 5(e ew5gv p5yn(see Table 13–4) to diffuse a distance of 15 ge5 wvy5(e5pn $\mu m$ in water at 20$^{\circ} $ C if its concentration varies over that distance from 1 mol/$m^3$ to 0.4 mol/$m^3$ Compare this “speed” to its rms (thermal) speed. The molecular mass of glycine is about 75 u. t $\approx$    s ([color=rgba(0, 0, 0, 0.85)]Round to one decimal places) $v_{diffuse}$    $ \times10^{ -5}$ m/s
$v_{rms}$    m/s

  Oxygen diffuses from the surface of insects to the interior through tiny tai;;uj* frde/3ejls 2ubes called tracheae. An average j jdi2;fe/*l s;3r aeutrachea 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 has been cali1jgv x 2*qun50o65emla b5l efbrated at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A precise steel tape measure has been calibrated at 20,su1br)5 mzq o$^{\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 wash r1kow 9n;:yug:qm 6* 4qjucp calibrated at normal room temperature. How much error will be made in a recipe calling for1 rqnqgy9w6o: pj; ck:umh 4u* 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 g fhuyo *8h:y4 wz),(ja/uftfe97 qlcras cylinder is initially 28 atm. After many balloons have been blown up, the gauge pressch/qtuo yu7:8jf *ryzff(e h4l)a,w9 ure 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 l nv789*(yoqxg2x-ryp -qb f(xrn4d j uength 6.5 m, width 3.1 m, and height 2.5 m. A xgu(on47jr xxfqp2 -dyq9yv*-8( bnrssume the temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter ikauo5vz,/ng dgf3no158-r i ds 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 technwik3*zx 7:2k4bigf hwbmb(8gz+hlp0iques is about z80bb+ hbl427*h : m (wgfkii zpk3xgw$10^{-12} N/m^2$ At such a pressure, how many molecules are there per $cm^3$ at 0$^{\circ} $C?    $\frac{molecules}{cm^3}$

  If a scuba diver fil jh(* uwucfj,)ls his lungs to full capacity of 5.5 L when 10 m below the surface, to what v j,u)fj(u*hwc olume would his lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle retur3:-pu kd))ha xr-ka6 t6nt4t nhg*gwrning from the Moon enters Earth’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 temp43axkn6w)tdn)rh h t6u:-gk-argpt * erature, the nose of a space vehicle must be made of special materials; indeed, part of it does vaporize, and this is seen as a bright blaze upon reentry.)    K

  The temperature of an ideal gas is increased xvy0k431pty i 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 8a3ns1-o5;tjnx*ql fsi b3 v zof 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 atmos:iv7nw5 q;o2v0n vpezpheric pressure at the surface of the Earth, estimate the total 7op zvwenvv ;502i:qnnumber of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contained inz3o /gh )ra 4 qaaqyb.jxu:e;5 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 gaugexa-3 o wpzs:f( pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmospheriz-as( ox:3pf wc pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl o7s)tl- cw e6cpf 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 gasoli16/ydoyqn4, wv8l vy xgu40 vine 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 Earthu4(rk : hqlp)q’s equator at 25$^{\circ} $C, but then was heated to 45$^{\circ} $C, how high above the Earth would the band be (assume equal everywhere)?    m

  A brass lid screws tightly onto a glass jar a nl ;bnuzh:19xt 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,ikb: 8qj2 *jt wai97xp7bqv9 z adopted in the 18$^{th}$ century, was a platinum bar with two very fine marks separated by what was defined to be exactly 1 m. If this standard bar was to be accurate to within $\pm1.0 \mu m$ how carefully would the trustees have needed to control the temperature? The coefficient of linear expansion for platinum is $ 9\times10^{ -6}C/^{-1}$. $\pm$ =    C$^{\circ} $

  A scuba tank, when fully charged, has a pressure of 1z6xp7os yv4 -m95 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 Earth lq/u: 4xv7/x u*ui qnn,g.gg 0t +iwhhis $ 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 gravitn nb1c, 7 fq5h+. y:vw/usqspey by tennis balls thrown vertically upward at it. How many tennis balls per second must rebound from the v yn+ hps.q 7f nb:u,wc/qs1e5lid elastically, assuming they have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter (spherical) bubble :1tupkf pc+sm vj2 +9zof air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the air behaves as a perfect gas. How large i+k+9:uftjmcp1z 2sp v s the bubble when it reaches the surface?    cm

  Calculate the total water va3 0hz8,k vvqgspor pressure in the air on the following two days: kh v sgzqv8,30
(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, and when it is7f*cualt, o (r a solid deep in the Earth where the temperature i*(, lrcot7uf as 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 gasf6t nt7d1 qxo( law to show that, for an ideal gas at constant pressure, the coefficient ofoqxnf( t1dt6 7 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.