Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodic;u- gnxz r+nq1 table or ;x qnnz+ug-r1 Appendix B.

Name several properties of ma a8mhq r7-)szaterials that could be exploited to make a thermometer.8za)rs7 am- hq

Which is larger, 1 C xx+ z4bd7v hzok1bg /.9nn9/ ht+rapk $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B is not insa6o qo: tr*:d9;w oxext m,wm;lx58y thermal equilibrium with system C, what can you say about the temperatures of A,q;y,;x*:o8 6xm 5a t:w wxdroletsmo9 B, and C?

A flat bimetallic strip consists of aluminum riveted to a strip ofn*5ea eihp h y nou90/ )x,fr:bza/lyz- (9bjk iron. When heated, the strip will bend. Which metal will be on the outside of the curve? [jan-*bbah( yz0yrpn zo:9u )k,fxe9 eih5/l/ 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 coefficientm8 k caw fn5d6p)yj6mqk1e(o m8n5u6t 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 diasjn4l7: t74mt r.s0p hse2pn ugram of a simple thermostat used 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 that conducts eleuhstr m:p7p0 t2jl47 s4e n.snctricity 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 a67 3dpwu+wwlfh3**h zp/.g8yp wac npre fixed at the ends often have a section in the shape of a znu36 3p*7h8w*h cpdl.wp/a+wywf g p U. Why?

A flat, uniform cylinder of lead floats in merc dz) ueb14xe*c2y el*tury at 0 $^{\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 of water,8p ucedzk1glrq/6 +s7lw z8 t6 the mercury initially de6zu+8qdk cs6wg8 pl1z/l7rt e scends a bit and then rises. Explain.

A glass container may brnt, +k0s 8nfjweak if one part of it is heated or cooled more rapidly than adjacent parts. Explain.+nwtnf j,s0k8

The principal virtue of Pyrex glass is thsv6 , t,t:ft :y2j.6z,o rbfrzkza 6grat its coefficient of linear expansion is much smaller than that for ordinary glass (Table 13t rttokjr ,vsbr6 6fg, 6zayz,z2:f:. –1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, a6t/vs co 1 x2drp eors)aizu/*6w2dk -ccurate 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 b33wz6 mzmx)cu+/hk m+wh;r -bn; cg uvottom and top to bulge so badly the can w)/hz-n;mw z3x g3hvmr+u ;muwc+bck 6ill not stand up. What has happened?

When a gas is rapidly compressed (say, b08 dxjm e4t5kgy pushing down a piston), its temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperature using the kinetic x jd8m0et45kg theory, in particular noting what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force opo31lji jy.09bk) yc0n9fnnurq 3/gn n an aluminum sphere submerged in water increase or decrease if the temperature is injunf90on.3n0 cy1)9pikjlqgyb 3 n/ r creased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law fodc8io9f o-z/y llows from kinetic theory and the relation between avd c 9fo-oz8y/ierage kinetic energy and the absolute temperature.

Explain in words how Gay-Lussaqy4l pb b.53tpc’s law follows from kinetic theory.

As you go higher in the Eoycgy to0n1w 4)rlf/)arth’s atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Ear3g6cke+ sfh s/th refers to the minimum speed an object must have to leave the Earth and ngsfh 6s+kc/e 3ever 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 quickl9:e1 prycyve7 y than water at room temperature. What can you infer about the molecular properties of on71yr p9y:ee vce relative to the other?

Explain why a hot humid day is famveoit3 xm4 q a8tgk 84,.p1e nb9uc5xr more uncomfortable than a hot dry day at the same3t8mone 8 q ebxc i5,mk4g41pa v.9uxt temperature.

Is it possible to boil water at room temperatv;x3uog n+n 2xure (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the s,3 uyndz5 kgh:+f2ts same but the humidity is different. Which is more dense, the dry air or the humid air at the satsy:hfs53kz+ u ng,2dme T? Explain.

Explain why it is dangrg9ec6 wj c)fu)3gj1 rerous to open the radiator cap of an overheated automobile enf j1g96rwc gc)u)ejr3gine.

Why does exhaled air uyl -:4;bafo7i 9gckjappear as a little white cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram copp eum47q5a6edd er penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare tu )15yypyhic)o the number in a silver ring ofy) c)5iy uhpy1 the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to b 5 2 6dfhoq r2jd-64yxowsfvu4e 68°F. What is this on the Celsius scale?fdhxw2-4f d4r6osu5q j o2yv6    $^{\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 teme .0-hndk/fcrperatures 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 alcohol column has length 11.82 cm at 6u,t l7k cj 168y5azdx.z1tcq9 xkm te0.0 u xm j66z zy7kta59lq,d81x.tct1k ce $^{\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 k v668o90.gtb fk iibo12 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 bui.x+,diz 5m 4m yfkpdy0.k,gvwlt of wrought iron approximately 300 m tall. Estimate how much its height changes between July (average temperature d kkizx +,,.mgd5myw4pyv .0fof 25°C) and January (average temperature of 2 $^{\circ} $ C). Ignore the angles of the iron beams, and treat the tower as a vertical beam.    m

  To make a secure fit, rivets that are largeofh x;: ;sz2c1mi,7ndebi)psr than the rivet hole are often used and the rivet is cooled (usually in dry ice) before it is placed inci71 po; sh;im)sxzfeb2 d: ,n 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 ap8cbo 2nf :wn 92tdsc+w:j;ywt 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 w*xsjk:z,f9foq *wjb1if;g w.ill be its change in volume if it is heated from.k*:9;wb gi1 f*qf ,jjfws oxz 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim wit1 jzvdzvnb :02h 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 m p;:cz nw3+cxoL 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 placn(;xsfj6 l1bhz674nuib )ae+heupl2ed in a ring 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 jwo4 ;jzsic:gs x:, u0in a long, narrow vessel so it can expand in essentially one di jw0s,sijx c z4:ou:g;rection only, show that the effective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the denshdvv*e6 :;o1kurv92 j p,ank lity $\rho$ 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 platk 4za:h6/d a85l qaipye of length l and width w has coefficient of linear expansion4a6y :ipaalz5dkh 8q / $\alpha$ 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 isotrl9)k0pkcg7m 3gauub 7opic 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 keeps3dc )hj7k6aebn.5te g perfect time at 1e gt3aced 7j.bhn)5k6 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 mercuryv*;:sdasqi s l*e;;6 u(vowf b thermometer has an inside diameter of 0.140 mm. The bulb has a u(ild;wbsfse ; o:;asv6q* *vvolume 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 r7 iv3 *rb8ly)(0bkw7fqy uzem adius 0.41 m is rotating about its axle on frictio(byy qk8urv*)fewl3zib770 m nless 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 (, klkjcl7v) ((xyygbstress is required to keep it at t,(klv7(xjk (y gyb) lchis length if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-sectiona; oeru 4yo1*6h nbcl6r:cnp+ql area 0.041$m^2$ is rigidly connected to two vertical steel girders. If the beam was installed when the temperature was 30$^{\circ} $ C, what stress is developed in the beam when the temperature drops to -30 $^{\circ} $ C (b) Is the ultimate strength of the steel exceeded? (c) What stress is developed if the beam is concrete and has a cross-sectional area of 0.13$m^2$ Will it fracture?

  A barrel of diameter 134.122 cmlh cu .pao(6:fw1jr* w 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 following temp0k 0ri1 i.w*es/xgevfw*d1q yeratures 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 temperature on the Fahrenheit scale? /)x fbk6uj+0 z retw(i   $^{\circ} $ F

  Typical temperatures in the interior of the Earth2r) shzvv 4yv z7k)(uefc 82eblyu/1 u 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 pres,dmwsw,+ ze(n o4l( whsure and a temperature of abou ohlszwm,e(n(w d4w,+t 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 gas wzmw)j b5hd5; g+p2jr law.    kg/$m^3$

  A storage tank contains 21.6 kg of nitrogenkyy:opkkdqvwm,s 6fdp ;e z( te(9 -83 ($N_2$) 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 STP6u7iaci q/ 7bxudp3 :a contains 18.5 kg of nitrogen ($N_2$)
(a) What is the volume of the tank? $\approx$   $m^3$(“Round to one decimal places)
(b) What is the pressure if an additional 15.0 kg of nitrogen is added without changing the temperature?    $ \times10^{5 }$Pa    atm

  If 18.75 mol of helium gas is5cr5mv(yj i;x1d s+pl at 10.0$^{\circ} $C and a gauge pressure of 0.350 atm, (a) calculate the volume of the helium gas under these conditions.    $m^3$
(b) Calculate the temperature if the gas is compressed to precisely half the volume at a gauge pressure of 1.00 atm.    $^{\circ} $ C

  What is the pressure inside a 35.0-L container holding 105.0 kg of argon gas voi*bszh4oh5 fgz4 p68j0 vh+at 3o 4ijosghh6*z805vp4 f +vhbz85 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg o2z y heg81 , fwmumkb5f1so3 vk0).ppo9ake6of $O_2$ 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 heati-y*tx0x wp+gr1.u qc ing the air inside the balloon, which makes it less dense than the air outq0*t c p+xr1.g-uyi wxside. Suppose the volume of a balloon is 1800 $m^3$ and the required lift is 2700 N (rough estimate of the weight of the equipment and passenger). Calculate the temperature of the air inside the balloon which will produce the required lift. Assume that the outside air temperature is 0 $^{\circ} $ C and that air is an ideal gas under these conditions. What factors limit the maximum altitude attainable by this method for a given load? (Neglect variables like wind.) $\approx$    $^{\circ} $ C(Round to the nearest integer)

  A tire is filled with aee ;/7 ug 5vao(piyy8qir at 15 $^{\circ} $ C to a gauge pressure of 220 kPa. If the tire reaches a temperature of 38 $^{\circ} $ C, what fraction of the original air must be removed if the original pressure of 220 kPa is to be maintained?    %

  If 61.5 L of oxygen at 18.0 jlibr 1kjufe+ ..fa 6(. yfbv-$^{\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 sf pi+-wot1 rohrd1)2 wea level and 20.0 $^{\circ} $ C. When it reaches an altitude of 3000 m, where the temperature is 5.0 $^{\circ} $ C and the pressure is only 0.70 atm, how will its volume compare to that at sea level?    times the original volume

  Calculate the number of mol y)*zou srx-5v8k)s rwphq8 n-ecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How 4 9l1usm0uomhmany molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) moleiodqc7 ;iyzbnoo-pc:*, 6y/as,    $ \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 voluml +x eijxk2a5*y- )mxhyy( sp3e 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 moleculeplka:ccl4j tl1rl77vim 4e/ )s of air are in each 2.0-L breath you inhale that were alsola)tmj l7 4ipr v41cek/cll:7 in the last breath Galileo took. [Hint: Assume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy ofomjq.l2/2lo.sh z e h/ b-.pak an oxygen molecule at STP? llz. eo/h/h-pmas2.q o j 2bk.   $ \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 atoms near the surface of the Sufzy )dtiuh: rbfr.j1h0;o 2s1 n at a temperature of about 6000f2:bo0 1r)rit uzyfjs; .d1 hh K.    m/s

  By what factor will the rms speed of gas molecules increase if the temperature75xa*gw mzr:w;/p m ye is increased from 0 *gw /7pye5rxm:awmz ;$^{\circ} $ C to 100 $^{\circ} $ C?   

  A gas is at 20 $^{\circ} $ C. To what temperature must it be raised to double the rms speed of its molecules?    $^{\circ} $ C

  Twelve molecules have the following speeds, given in units of km/s: 6, 2, 4,u2r vwri-jo( w sg++f0 6, 0, 4, 1, 8, 5,(s0ruorg w-+i w2jvf+ 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at 20.0 fp o)sp,n8uj 8es3 tad*g6/ky $^{\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 f g8db6/g+o rdh xzwoy:,(v8q its volume is held constant, by what factor doh z+gvxbd6d8 ,o8( :gyqrowf/es $v_{rms}$ change?   

Show that the rms speed of molecules in am7cf 7j,kd1y.rc 4 xqy 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 te4cic5 f 77hheumperature, the ratio of their rms speeds is equal to the inverse ratio of the square roots of their 77i uefhc c5h4molecular masses.

  What is the rms speed of nitrogen molecules conaid4vzuen mb/wez;j-,d; ((wq r1lg- tained 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 qq 05b :2ku(ib3ka.2zfpilww 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 molecules at 6a o4ub9shnka4/ ju84vws fl,STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whosewp/f*v ;f3 xfj vq-q2xp og8eji 9(pv( molecular mass is 89 u in a living cell at 37e-vjp(92g;fw x/po 3 fvv fpx(qqij*8 $^{\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 bey*sltp5h -:aw gble qn;n 9aa42m9kn8 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 uranium,i3guigv,; :eo $^{235}$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 preslasd v;e9r.kkj,.l* fh jv 5g,sure, 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 t.fiiqgtz5;7f1q0e 3-oz yu f is (a) 9u;f 5otq3e.zi z qi1gtf0y-f 70 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity is 55(w ep0 qqcvb ev(lf+)0% on a day when the temper5+qev(f vl0ew) cqp(bature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where watate2kb9n j; p i0uhx2mt:h-d7 er boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is 0.72; r82c ( mvhzs7bj/glg atm, estimate the temr lmsb782jchgz/v(;gperature at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of water nyx;3l39jka/jsdwl+ e 80ge+dtqu o) bcx/s, is 530 Pa and the relative huja/; wc3ln o/dk+,0 l )8gts qdu s9+3eyxbejxmidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the temperfp(ct+d: a )dtature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate prescxu m mhetl: 6(x,75ejsure inside a pressure cooker if the water is boiling at a temperature of 120 l (,5u xxme6:mj7thec$^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a roomkau;y .nwx;-a0qh0 pf 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 point of vx 2b1 mf)jivv.-yog75 $^{\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 nenk3zl*s,d;7i)nchqq osb 9b.f/pz 1reded for a glycine molecule (see Table 13–4) to diffuse a discz3sib;f pqh r7bqs,.*nz 1 ln/ko9)d tance 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 thsi/:po8gzu h*e surface of insects to the interior through tiny tubes called tracheae. An average trachea is about 2 mm long and:u szgohpi/* 8 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 measur(:i sf 0cs8; cn)rb mcdhr1pb8e 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 precise steel tape measure has been calibzb:36stxcj gys)q0qhi44)l drated 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-dd+o2 3f5g xk olxo-i much error will be made in a recipe calling fof-3o 2- d +lidk5xxgoor 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 cylindercvka;4r(:d ; gbb(siw is initially 28 atm. After many balloons rkswb 4va;c (ig;:(b dhave been blown up, the gauge pressure has decreased to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number x5ymr-shq 0i1)oqip 7of air molecules in a room of length 6.5 m, width 3.1 m, and height 2.5 m. Assume thp 7qi oqyi)h0- s1mxr5e temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density-(b ;pjxvu.vid5ak s, u8qys 7u 3w)dcfu5eg) of matter is about one atom per $cm^3$ mainly hydrogen atoms, and the temperature is about 2.7 K. Calculate the rms speed of these hydrogen atoms, and the pressure (in atmospheres).$v_{rms}$ =    m/s    $ \times10^{-22 }$ atm

  The lowest pressure attainable using the best,rx15zebl jn , available vacuum techniques is aboxb,le,zn j51r ut $10^{-12} N/m^2$ At such a pressure, how many molecules are there per $cm^3$ at 0$^{\circ} $C?    $\frac{molecules}{cm^3}$

  If a scuba diver filuxf2f7t7* 8etr 4oeiqls his lungs to full capacity of 5.5 L when 10 m below the surface, t ri*qefot e77t 2ux4f8o what volume would his lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning ughlwa0k-;4 l j eze18from 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 belh-k84a1 ue wjl 0ge;z 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 incr,pz6hz4u2ep6zduk s. eased 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 770tx /04o.rmpz p )cts:vm$^2$ (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 pressu- 9ns ie*v wm;l+petx :ca;.oare at the surface of the Earth, estimate the total number of atvoa c ;n-ex;.lew:p* 9 s+imair molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecul*pc;hfmi (r+ b,7,bkt,j ozc ces 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 oxyg8fwc5.6q3cx6 ouq kahen used in a hospital has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure, is constant at 2.4 L/min.665 ua chfkcow8qx3q. $\approx$    hour

  An iron cube floats in a bowl of liquid mercury a k/n+bp5 6b v2nkv*nejxjlc *vajw;77t 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 gasol99dyy u tsit tf917jb8ine 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 tn olxm55o2mk2co+j0ldvv v 53i/d8 l hhe 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 jar *i dbgytuef** 57 + mjzq//jfnat 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 th .(z zvjya31j8v (vu cywn80vp; zt*ese 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 r+e*: 9v ux:g evgk88 xd68hnob6fcida 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 is ieh*/3 qh0,g4qc5b,kx myd ao $ 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 againsu; b (p0n/n,ad7csigpt gravity by tennis balls thrown vertically upward at it. How many tennis balls per second must rebound from t7;pu(bna gs0nci/d , phe lid elastically, assuming they have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter (sphericarlj6 o c 0ic*.+fjq;usl) bubble of 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 la6 r.j;s+jfqucic 0l*orge is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure in the air on the following two days: m5n;tzxg(xqkj-.k s- q(nk.-msxgk;- z 5jxt
(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 percent6 y9bemll)ubxh y: *-b difference in the density of iron at STP, and when it is a solid de: -u* yh l96beym)xlbbep in the Earth where the temperature is 2000$^{\circ} $C and under 5000 atm of pressure. Assume the bulk modulus (90$\times 10^9N/m^2$) and the coefficient of volume expansion do not vary with temperature and are the same as at STP.    %  ----待选择----decreaseincrease 

(a) Use the ideal gas law toy8vyx o2o:xaicted .q(0i,)c show that, for an ideal gas at constant pressure, the coefficient of(.yo qyiae: ocvxci) t 280,dx 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.

  In humid climates, people constantly dehumidify their cellars to prevent rogh*: +ca64lrw , g d9se-+afqc sh:fegt and milde ff:6 esag4aw c-hgd,qh:*g sec9r+l+w. If the cellar in a house (kept at 20$^{\circ} $C) has 95 $m^2$ of floor space and a ceiling height of 2.8 m, what is the mass of water that must be removed from it to drop the humidity from 95% to a more reasonable 30%?    kg