Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodic/zz cj:zyrc/rp.m1+2e8 6nc smv)rka table or Azkpz8rm+c .cj 2zvc6:me/s r/ny)a1r ppendix B.

Name several properties of materials that could be exploited to make a thermomhvg4ddjqy)q g(o*/ d qutw 9+-ete)gjqy*/ dh-4 d(9vqgow uqtd+r.

Which is larger, 1 Cdqa7sq4 6ueohc ( ;i,lb)drq* $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B is not i 8q : 0yor0wb4m2gfzxhn thermal equilibrium with system C, what can you say about the oyz2x00 mgr:whb4q8ftemperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to a sts6 smwvn9+ u/krip of iron. When heated, the strip will bend. Whin+svsmk 69w/uch metal will be on the outside of the curve? [Hint: See Table 13–1.] Why?

In the relation $\Delta$L = $\alpha$ $L_0$ $\Delta$T, should $L_0$ be the initial length, the final length, or does it matter? Explain.

The units for the coefficient of linear expansio9 ku )r8tuvps4n $\alpha$ 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 ue ,*)h+wq vmxnopud/g,p6w 3jsed to 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 twpgv*x du3mjh,n)ew+op /q6,hat 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 enh j, 2ek*yrw-/ pncn+cds often have a section in the shape of a p /jk2*her+ycw nc,-nU. Why?

A flat, uniform cylinder of lead floats in mercury at 07wzvqfed8+u q.x,, zplr0 h 2n $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometer is first placed in a hot tub ofat3wzxv6) jkv5ve :ekeqk)21 water, the mercury initially descendv21x5kwkt:)) 6z eee3avq vj ks a bit and then rises. Explain.

A glass container may break if one part of it is heated or cooled more rapidly mg/pc)m4thvzv+/0ptt4 mj4b thanj4v4p tc40 /ptg/+mm b)h ztmv adjacent parts. Explain.

The principal virtue of Pyrex glass is that its coefficient of linear expansionch7jyx t7(say(wk9w ps46 e p+ is much smaller than that for ordinary glass (Ta+hesy yj((k9stc7wpa 6p 4xw7ble 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, r 3w jljoucyf-vgxy/4z ad - l4;1+(sraccurate 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 bottotl 6 5+gqtqh6bbp d+3tm and top to bulge so badly the can will notdqqthtp3bb+t +lg66 5 stand up. What has happened?

When a gas is rapidly compressed (say, by pushing down a syeaab d-f q+4mnfa-+1j; ch 8piston), its temperature increases. When a gas expands against a pissafm;1 y4bh aa cj+8 e--+fndqton, 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 subxipw5h72k, (pa i2b,mbw9 joymerged in water increase or decrea,i ha2m5k9b,ybjw wi2xop7 (pse if the temperature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theory and the relatiod* in( wwbg8h4x4vki ,n between average kinetic energy and the absox dkbg (wi844vw*h,inlute temperature.

Explain in words how Gay-Lussac’s law follows from kinetic theov 4a-(q 3ffskiry.

As you go higher in the Earth’s c6ngj*f/g6johiz d*0 w, :*c:wdv4 ibml:cyzatmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to p1gpf*hj gi 7iw+3j.ithe 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 fi+1p gw73g .j j*pihifor 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 c69b ;hf.f9sjv icw:c ban you infer about the moleccjfw9 i hbbfvcs:9 6;.ular properties of one relative to the other?

Explain why a hot humid day is far more uncomfortable than a hot dry day at th +uftrz+.ad6x alw0s8+ 3 nfoqe n z 63af+us+od tqx.8fl0+arwsame temperature.

Is it possible to boil water at room temperau.y 63 8dndibnture (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the humidity pga;+ ;pf+lhe iw7sxp 10ditnhqh z43/+n(unis different. Which is more dense, the dry as+ iqph wz3/ta4 dglxn ;0 u7; (h++iphpefn1nir or the humid air at the same T? Explain.

Explain why it is da ywf.h/s9x bk5xub*n0ngerous to open the radiator cap of an overheated automobile .s50b9 b*xywux f hk/nengine.

Why does exhaled air appear as a little white cloud in the win aam e e1i-ma)9dh0c+hter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram c j5k sf7 ugyydcmb-8 21h,,ubuopper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring comb mahedryg0bh*4h71)j bai49n; ztl 9pare to the number in a zy9ehr41d gh7 )bihm b9l;n 0ajt4*b asilver ring of the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this on the Celsius scal vvp:or+gkzp3r se7b)z6fxee389s e+e?+3s86r:v pes zp79v+zr)kbeo xe ge3f   $^{\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 li*oo a:zqznhv d1 ;pc26/k,mi owest 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 alcoho16s m-jrb 7hip6i +adtl column has length 11.82 cm at 0.-6hs d17jmpt+6b raii0 $^{\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 bytc dsmdwh;/9l176m avf0 nc8uilt 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 300 m ta))9gi24xe 6he01 iepojuhs nwll. Estimate how much its height changes between July (average temperature of 25°C) new2 0uoh9eiixe g4)1s j6ph)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 5 v*tv ea1qieb3hib hzm0,i--rivet hole are often used and the rivet is cooled (usually in tvie 1z-m 0q ia5hh3evbib*,- dry ice) before it is placed in the hole. A steel rivet 1.871 cm in diameter is to be placed in a hole 1.869 cm in diameter at 20 $^{\circ} $ C. To what temperature must the rivet be cooled if it is to fit in the hole?    $^{\circ} $ C

  The density of water at 4u.c f+gk-*jix $^{\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 voluf m axm8b++7cjme if it is heated fromc8jbamf++x7 m 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to d9hvy,5 ufo:c0hvl.sthe 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 wa6ach4kw 7awc-ter 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 iron. i7gx u+i pczq/u i:tv.tq/:h.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, yk3;gd0y -zgm-m5o8b olz7bdnarrow 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 vo;k5 y8 mgoyz7zbm lg3b0 d--dolume expansion $\beta$.

(a) Show that the change in the densiwxhp- ,k4k3 frty $\rho$ 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 len0 ike1ey)ou * f,:(jm4 bwhfuggth l and width w has coefficient of linear exeb m1ky,efu) gi uh:(fw*j0o4pansion $\alpha$ 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 solirk/-6kxl mg icre80, ud, $\beta$ = 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 grah lqetn )ds.; r85:dphm/y /svndfather clock is made of brass and keeps perfect time at 17n5.ht:/sp dr)v ms;ldq/ yhe 8 $^{\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 in/0 7 vsxxg.co zsg3se2side diameter of 0.140 mm. The bulb vszgxg 0 os. 7csx23/ehas a volume of 0.255 $cm^3$ How far will the thread of mercury move when the temperature changes from 11.5 $^{\circ} $ C to 33.0 $^{\circ} $ C? Take into account expansion of the Pyrex glass.    cm(b) Determine a formula for the length of the mercury column in terms of relevant variables. Ignore tube volume compared to bulb volume.

  A 23.4-kg solid aluminum cylindrical wheel of radius 0.41 m is rotating about i8 s6bong2n k0pt pbg62o80ksnn s axle on frictionless bearings with angular velocity $\omega$ = 32.8 rad/s If its temperature is now raised from 20.0 $^{\circ} $ C to 75.0 $^{\circ} $ C, what is the fractional change in $\omega$?   

  An aluminum bar has the desired length when at 15°C. How much stress is recnlle0r 8j+p1 quired to keep it at this length if the temperature incrlj0n8 c+e1l rpeases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-sectional area 0.0h .uxim; n(9de41$m^2$ 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 atr6u 2hj k,7n m y,+l1n3vhtpnj 20$^{\circ} $ C is to be enclosed by an iron band. The circular band has an inside diameter of 134.110 cm at 20$^{\circ} $ C. It is 7.4 cm wide and 0.65 cm thick.
(a) To what temperature must the band be heated so that it will fit over the barrel? $\approx$   $^{\circ} $ C(Round to the nearest integer)
(b) What will be the tension in the band when it cools to 20$^{\circ} $ C?    N

  What are the following tem 4+l )wbea *ji2w7cqpxperatures 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 what temperatur fzqv.;5z iyq:7d 6ybte on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun are about 40005x9uwg;d dl mo3k28mo $^{\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 enginbxiwu c2:h t17e, air at atmospheric pressure and a temperature of:1uih wxb2 tc7 about 20$^{\circ} $C is compressed in the cylinder by a piston to $\frac{1}{9}$ of its original volume (compression ratio = 9.0). Estimate the temperature of the compressed air, assuming the pressure reaches 40 atm.    $^{\circ} $ C

  Calculate the density of oxygen at STP using the im)dna9hw7gv +deal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg 8*13y vdr0l kd lrz3cbof 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 contaiwi q4 5;ptj7dmns 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 a7om o w-ip9r;yt 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 105q/.k nz3l/re t.0 kg of argon gas at 385 q /letkn3. r/zK?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg o:jimaecpnbl 73y,:u4 q7ld l*f $O_2$ gas at a gauge pressure of 8.70 atm. If the oxygen is replaced by helium, how many kilograms of the latter will be needed to produce a gauge pressure of 7.00 atm?    kg He

  A hot-air balloon achihf)827 izfdir eves its buoyant lift by heating the air inside the balloon, which makes it less dense than the air outside. Sup)78 z hdf2iirfpose the volume of a balloon is 1800 $m^3$ and the required lift is 2700 N (rough estimate of the weight of the equipment and passenger). Calculate the temperature of the air inside the balloon which will produce the required lift. Assume that the outside air temperature is 0 $^{\circ} $ C and that air is an ideal gas under these conditions. What factors limit the maximum altitude attainable by this method for a given load? (Neglect variables like wind.) $\approx$    $^{\circ} $ C(Round to the nearest integer)

  A tire is filled with a6ws fz(k*l.ua ir 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 ix wj-b,rf ,pi99l6t;bkm fx.18.0 $^{\circ} $ C and an absolute pressure of 2.45 atm are compressed to 48.8 L and at the same time the temperature is raised to 50.0°C, what will the new pressure be?    atm

  A helium-filled balloon escapes a child’s hand at sea ysfx2hwu a;bh49k,dzd .wd+ 4level 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 molec )g gy(icj+3jqules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How many molecu,p ;;c nnq5;itt.qm fgles?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) moles,4-isayex w-m/:dxet i 8 zn.*ps7 joe+    $ \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 voluma,w)duog og.3 e 5.1$ \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 breath you inhale that werwubto1r7*rp , e also in the last breath Galileo took. [Hint: Assume the atmosphere p *obr17u ,twris about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of adhyw256 h p wu3hdi/*n*bf8ocn oxygen molecule at STP? *3iw2hc*d 5n8h wuo6fh /yp bd   $ \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 + 09ck5v etbzlatoms near the surface of the Sun at a temperature of about 60c l0b9+evtz5 k00 K.    m/s

  By what factor will the rmsa3yf,t3/nu ue speed of gas molecules increase if the temperature is increasede,/3 tu3afny u 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:(t 7u niu(idy2 w;fjk( 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. (iwidtf j7(u(kn;u y 2Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at 20.0v*dyt-zn.b y u3 (8o) a0wv6aas nxu(d $^{\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 eznaa2.8j v9 nzsh8ocj+ 8+j xvolume is held constant, by what factor does cj x j2znan+ azj88oh9.+s8ve$v_{rms}$ change?   

Show that the rms speed of molecules in a gas is given by y,.(mju,jhjhaehw,q7 j 3k 2g$v_{rms}$ = $\sqrt{3P\\rho}$ 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 temperadf/e,*5 ,c9bh lxtfblture, the ratio of their rms speeds5/*lht,fb, bd 9cfxle is equal to the inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen molecules contained in an 8.5rz7sbiq 9v;2v $-m^3$ volume at 2.1 atm if the total amount of nitrogen is 1300 mol?    m/s

  Calculate (a) the rms s+giz9wf1uflsd3+ b-3j.jm u cto1fs8 peed 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 nitrogen moleculexujnuaudk/lqp/ c s+*t* /; 4ds at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose mw -0tst )cl ;wx0zcqq7olecular mass is 89 u in a livintc0tqs;xq z)- 0ww7clg cell 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 writtez; b/w-xdv;po n 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 ur1ub0+3yge:8w8x axbqp ,w bny2iny tt44d9r ganium, $^{235}$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 presfob;qj2 *vz. psure, in what phases can $CO_2$ exist? (b) For what range of pressures and temperatures can $CO_2$ be a liquid? Refer to Fig. 13–21.

Water is in which phase when the pressure is 0.01 atm and the temperature is mm ckm ovt3iw0 np*2 -70;pwhu(a) 93i*cph-w np 00mwu v;mtk7mo20 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if therjq s je0,3z9q humidity is 50% on a day when the temperaq 0jsz9jre,q3 ture is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water bot dnl ,/p .c(ib2jy*cvils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in b3a/ht c5(,cbvm+ lmb the mountains is 0.72 atm, estimate (mcach ,bl5vb 3+t/bm the temperature at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of waterh4;astaox) 07 + *poinu1lge+gc-p hp is 530 Pa and the relative hum apg*t0x sie)+ oc1- un+h 4ha;plgpo7idity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when t35 t6w4bs s*npb -i8oy e3gccthe temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximac :rr2q w;i)8x i)k/gotrgj pmz-c 7l6te pressure inside a pressure cooker if the water is boiling at a temperature ofi-c8 )lo)kgc/r q2;mr7:ij xzr6tg wp 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 dz;aa9lsh 2mp sl2 -h4680$m^3$ at 25 $^{\circ} $ C is 80%, what mass of water can still evaporate from an open pan?    kg

  Air that is at its dew pointyaclo)-:so h;6 lbg+ m 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 q,ov+cm4n 6xsmolecule (see Table 13–4) to diffuse a distancc o+q4xsv6n, me 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 the surface of insects to the interior through 4 * x-iuu03y psjw:xmwy:;n7*ekjl xslj2kz* tiny tubes called sp 0 wnl * ym-u**kz7juk3e x4wls;xjyxj::i2tracheae. An average trachea is about 2 mm long and has cross-sectional area of $ 2\times10^{-9 } m^2$ Assuming the concentration of oxygen inside is half what it is outside in the atmosphere,
(a) show that the concentration of oxygen in the air (assume 21% is oxygen) at 20$^{\circ} $ C is about 8.7 mol/$m^3$ then $\approx$    mol/$m^3$(Round to one decimal places)
(b) calculate the diffusion rate J,    $ \times10^{-11 }$ mol/s
(c) estimate the average time for a molecule to diffuse in. Assume the diffusion constant is $ 1\times10^{-5 } m^2/s$    s

  A precise steel tape measure has been calib/n2 z/rveqboa sy+ -vo)fb/y9rated 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/pdfe e :cbmx.kbq ka5*:4b4 m calibrated at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A Pyrex measuring cup was calibrated at normal room temperature. How much erro vvn+f)oxv*0do c a,h9r will be made in a recipe calling for 300 vn,+vd f* 0xavc o9)homL 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 ihjg.onu 93ib qe +vhni8 ,2lw qbae*46db6rf8s initially 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm+4e2weu.no*96v6bqigb ,nrihd b3hq8 l a8jf. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air molecules in a room es:s 0r. lkl1*u6vzri of length 6.5 m, width 3.1 m, and s*u 6rs0:.kvel1 ilr zheight 2.5 m. Assume the temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is about one atom pe,t-oq (q33jbswp(cn cr $cm^3$ mainly hydrogen atoms, and the temperature is about 2.7 K. Calculate the rms speed of these hydrogen atoms, and the pressure (in atmospheres).$v_{rms}$ =    m/s    $ \times10^{-22 }$ atm

  The lowest pressure attainable using the best available vacuum techniques is3r+-sev h7v4kr9woxvvbr1( xi *6d wa about s 3ihrwx-br9+x(v 1 67w avvdvkoe*4r$10^{-12} N/m^2$ 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 below tut84sm t,wd4n to;i w+he surface, 8si+utw,wo 44d t;nmtto what volume would his lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning frw9su w+xgvma5s2kn7, om 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 temperature, the nose of a space vehicle must be made of special materials; +7m,aw9xs 5snvk2w gu indeed, part of it does vaporize, and this is seen as a bright blaze upon reentry.)    K

  The temperature of an.5y::d js atjh 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 volume of t j5j .t128 g6f;tn;oynpoxgj770m$^2$ (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 pressureee**oc(b ts tm5-2sh i at the surface of the Earth, estimate the total number of air molecules c-* 5 tieemt( s2bh*soin the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen moleculeisk*k h-ks1 9p c/bdg:s contained 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 = 2000z.hzd cuev 5c(v*vcjfo 7702g psi (13,800 kPa) anfv ovvc7u*hcez 2 d( 5c0jzg.7d at T = 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, z(o6cz zaesb0sw. ka1y, .st of liquid mercury at 0$^{\circ} $C. (a) If the temperature is raised to 25$^{\circ} $C, will the cube float higher or lower in the mercury? ----待选择----lowerheigher 
(b) By what percent will the fraction of volume submerged change?    %

  The density of gasoline at 0-,nsvbvv 8 sz .6.bt5dwpoc.te/ qk4 l$^{\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 arog8;s8p wf 0twaund the Earth’s equator at 25$^{\circ} $C, but then was heated to 45$^{\circ} $C, how high above the Earth would the band be (assume equal everywhere)?    m

  A brass lid screws tightly onto a glass ja/odu 0 dmdd6)nrdn+ bjju*t ,:r 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 sta)u1mehl(x ft21c*k lu ndard, 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 charelx;9 sw 1lx fp+.0qt5x9szy vged, has a pressure of 195 atm at 20$^{\circ} $C. The volume of the tank is 11.3 L.
(a) What would the volume of the air be at 1.00 atm and at the same temperature?    L
(b) Before entering the water, a person consumes 2.0 L of air in each breath, and breathes 12 times a minute. At this rate, how long would the tank last?    min
(c) At a depth of 20.0 m of sea water and temperature of 10$^{\circ} $C, how long would the same tank last assuming the breathing rate does not change?    min

  The escape speed from the Earth isgobr/,q4fi rvm.8fv ) $ 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 ag49q 2vllq.r kmainst gravity by tennis balls thrown vertically upward at it. How many tennis balls per second must rebound from the lid elastically, assuming they qrkv4mql 92.l have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-dv+fwe m: 0gmx (.cfr vitvrht .9:r8k0iameter (spherical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature is conxr : rf8e9v. (ictgtm0 .rv:0h+f wmkvstant 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 followtv / plgyzo(t5r 08mk7ing two days: (klgr 0578m vpo/z tty
(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 vsfj( e4 wkb5k58v+b mis a solid deep in the Earth wherf+v b 5ke8wbvj 5m4(ske the temperature is 2000$^{\circ} $C and under 5000 atm of pressure. Assume the bulk modulus (90$\times 10^9N/m^2$) and the coefficient of volume expansion do not vary with temperature and are the same as at STP.    %  ----待选择----decreaseincrease 

(a) Use the ideal gas law to show that, for an ideal gas at x/zmy8fid3p0 s u zy/ h*:)qztconstant pressure, the coefficient of volume8zp 3 /0: ifzxz)/ yd*qmuhsyt 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.

  In humid climates, people constantly dehumidifyoch9eowy z6ji np 2di6b5.93n their cellars to prevent rot and mildew. If the cellar in a house (5p2n9jwyh .o93iz 6nbio6c dekept 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