Which has more atoms: 1 kg of iron or 1 kg of a -sff)soc y0uvi/*fl/) 7 t+*xrupwl iluminum? See the periodic table or f vcyu7o* wx+) i* /0us-ltprifs )fl/Appendix B.

Name several properties of materials that could be exploited to make a therm4m0jm)tthq + +*e bddqj61c hpomet * d4e+mtqp h)t bdm0qh1+6jjcer.

Which is larger, 1 Cfxb:uq*x2hv3c(/s8 j .o1iny k(etnf $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B is not pxd,-:y q8)/d9 yay m1yexgrkin thermal equilibrium with system C, aym1- pd)g kx89eyr :x qd/y,ywhat can you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of .b;t-jzq -scq aluminum riveted to a strip of iron. When heated, the strip will bend. Which metal will be on the outside of the tj-csbz;qq-. 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 expansiony/-g0. nj sz6g5khbpwn2gv2t $\alpha$ 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 g9oezx 1qt .:kdiagram of a simple thermostat used to control a furnace (or other heating or cooling system). The bimetallic strip consis :tzq kx9goe.1ts 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 g+qcfecc6n 5evyswixa..0 1- a section in the shape of a U. W..cv-n e0e cg + i1aqc5fsyw6xhy?

A flat, uniform cylinder of leao4-0 ) ;5 xsf)d9wtufumabx qud 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-glass thermometer is first placed in a hot tub zg57368szkqlqe m, lgof water, the 3l g kq8z q,mgsel765zmercury initially descends a bit and then rises. Explain.

A glass container may break if one ;vab10y6ci 8 zpzvtt*part of it is heated or cooled more rapidly than adjacent parts. Expla0z v typaiv*b8z;1 6tcin.

The principal virtue of Pyrex glass is that itsez r4llllw1 uv+5*+ hi coefficient of linear expansion is much smaller than that for ordinary glass (Tab5v+h4+ull *wie lr l1zle 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurate at 207 hi)no8z hu1wkm4vk:)-4 v7ollq mc u $^{\circ} $ C, run fast or slow on a hot day (30 $^{\circ} $ C)? Explain. The clock uses a pendulum supported on a long, thin brass rod.

Freezing a can of soda will cause its bottom and top to bulge so badly tha .2t llt4o mx8aa)bd7a/ea7qe can will not stand up. What has happenedt ba2d)amla8otl. xeaa74 7 /q?

When a gas is rapidly com enaya3:g4* .jhsm 8wy34zmdgpressed (say, by pushing down a piston), its temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperature using the kinetic theory, in particular noting what happens to the momentum om a44w s *a:gy8gjzhn ye3dm3.f molecules when they strike the moving piston.

Will the buoyant force on an alumin fc1jrnu8 v mdr4;+m*xx-:hq6fdbw,bum sphere submerged in water increase or decrease if the tempeb *d-wmf 6b ,;xnvfc:dm4r8+j1xqru hrature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetiz3 z 7;zjvg6gyw/( hqqc theory and the relation between average kinetic energy a yvgq3 zhz (j7wz/q6g;nd the absolute temperature.

Explain in words how Gay-Lussac’s law follows from kinetic theo 2tnk,.b0kyyd ry.

As you go higher in the Earth’s atmosphere, the ratio 0 .ochzj4zkg z8a)w v./ j4ujjof $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed an object must have tod2kiy mm1d +vc v7jw80 leave the Earth and never return. The escape velocity for the Moon is cd7m1dw2vi +ky8j 0mvabout 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 it(5j tdo7 eey+nfer about the molecular properties of one relative to the ot+5 ytd jeo(7ether?

Explain why a hot humid day isvzj8.mmvd*ir 0of76 q far more uncomfortable than a hot dry day at the same temperatd*vj7z v q8.o0immf 6rure.

Is it possible to boil water at room igc 5jc-gu0 :fj1l2 hs:ty0patemperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when we6 6n2gb5l,j0urwl zthe air temperature is the same but the humidity is differenwj665nlg0lu ,zb erw2 t. Which is more dense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap of an ougk/ hf jca)3*verheated automobile engine. k/3g*ajhu c)f

Why does exhaled air appudgsu6hsw; n f6mmtuz(5918 tear as a little white cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-g faoa a147fdm*ram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atu*q(kip5i hw tvet0 yx+ 2pz2-t hhw;-qn* u:doms in a 26.5-gram gold ring compare to the number in a silver ring of the same massp+0xwz :2uvnttt dih kwy*2eq;*h-ihu(-5qp?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this on the Cer 6.cczbl86lac;y0 f3)tvy wflsius scale?lwa63c)6r y b clff8z;.0tcvy   $^{\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 67 rl(o1ewdqob uffwl)*s4l/ 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 alcohol column has len ,v29ujmbks j(f e;h/ud*sok a 1m5p0;nmcd4agth 11.82 cm at 0.0 a/5vued jsu kms 92(0f4job; 1; apck*mhdnm,$^{\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 bun r-bckys 75)zilt 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 aplx;j- py b0zj9x cg2dky2n++b proximately 300 m tall. Estimate how much its height changes between July (avnb2bg xc 9jk++lxy;2z djy-0perage temperature of 25°C) and January (average temperature of 2 $^{\circ} $ C). Ignore the angles of the iron beams, and treat the tower as a vertical beam.    m

  To make a secure fit, rivets that are larger thbt o 5-zvbd5v ndp.7b -hq*zk2an the rivet hole are often used and the rivet is cooled (usually in dry ice) before it is placed in the hole. A steel rivet 1.871 cm in db.*b5v nthvq-5zb-7 k d dozp2iameter 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 waternb;d. t u fql3ulgui1-6 0*ccy at 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 wilb0lqi m67 14tavp6f q3u: ap8uwah g(ll be its change in volume if it i fp4l3m(p7au0g ia1l6q u6hqtb8 w:vas heated from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to thny(nbc+g+ct id o;n iz1m+eyb7rk1)( e 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 5 m*ta01d;zj hf5.50 mL of water at 20 $^{\circ} $ C completely fills a container to the brim. When the container and the water are heated to 60 $^{\circ} $ C, 0.35 g of water is lost. (a) What is the coefficient of volume expansion of the container?    $ \times10^{-5 }$ /$C^0$(b) What is the most likely material of the container? The density of water at 60°C is 0.98324g/ml.

  (a) A brass plug is to be placedrjbcf . o:z,ue,+*cbkyu4rl 2 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 in agz(gl v28kh-.b g slg; long, narrow vessel so it can expand in essentially one direction only, show that the effective coefficient of linear expansion is approximately equal to the c;zg (gs 2hlv-lkgg8b .oefficient of volume expansion $\beta$.

(a) Show that the chanhelb 66i :l(jsge 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 le:1 v8vqqaig im.6p5n sngth l and width w has coefficient of linear exm.gsvn85v qap :1iqi6pansion $\alpha$ 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 isotropicuj0,o4b8 n*gpf9 ic rx 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 n5omn jy3za11c oa4h1dkm+7aclock is made of brass and keeps perfect time at 17 an3o411h 5a7mm1o nyjzkcd+a$^{\circ} $ C. How much time is gained or lost in a year if the clock is kept at 25 $^{\circ} $ C? (Assume the frequency dependence on length for a simple pendulum applies.)$\approx$    min(Round to the nearest integer)

  (a) The tube of a mercury thermometer has an inside diameter of 0.140 )msnk;oy 61immm. The bulb has a vos; 6o)iymnm 1klume 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 oto ,t+rn :ogvw 7nq3i(tt8 zt6f radius 0.41 m is rotating about its axle on frictionless bearings wi6(7tg +t t o vn:to,38irtqwznth 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 dgu eks,j 19fs5*pdz;2g 2oa cat 15°C. How much stress is required to keep it at this length if the j,z21 kf52scddp ;sageg9*uo temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steermqx j vhe.peno 3h80,5u r;ajdfsbp4, (fg(/l I-beam of cross-sectional area 0.041$m^2$ is rigidly connected to two vertical steel girders. If the beam was installed when the temperature was 30$^{\circ} $ C, what stress is developed in the beam when the temperature drops to -30 $^{\circ} $ C (b) Is the ultimate strength of the steel exceeded? (c) What stress is developed if the beam is concrete and has a cross-sectional area of 0.13$m^2$ Will it fracture?

  A barrel of diameter 134.122 l+ht0w8ay+ s *vi wue+9)uwlycm 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 t,oq5rgv1 vk0iemperatures 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 oi7xs/x-8-y rwj5 1()vm l*a mtbx eliun the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior 0 p(oudn*j*43kicf l sof the Earth and Sun are about 4000$^{\circ} $ C and $ \times10^{6 }$ $^{\circ} $ C respectively.
(a) What are these temperatures in kelvins?    K    $ \times10^{ 6}$K
(b) What percent error is made in each case if a person forgets to change $^{\circ} $ C to K? $\approx$    %(Round to the nearest integer) $\approx$    %(Round to three decimal places)

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

  In an internal combustion engine, air at atmospheric pressure 6uccxjr3)c b j 8e8 ;8uolm6l0.hvi tnand a temperature of about 20)8b .jc llh3vuu 68 jtc0nx8e; 6cmrio$^{\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 o4w1np3 b;hbf 6 qvsoxgw 8u:h 5k**pvkf oxygen at STP using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg lxl.( nxben/daz(n7e2q+ 4h t of nitrogen ($N_2$) at an absolute pressure of 3.65 atm. What will the pressure be if the nitrogen is replaced by an equal mass of $CO_2$    atm

  A storage tank at STP contains 18.5 kg of nitrccia1a9vg *w6 ogen ($N_2$)
(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 heliume0rdp6dv:t;mp51gd q gas is at 10.0$^{\circ} $C and a gauge pressure of 0.350 atm, (a) calculate the volume of the helium gas under these conditions.    $m^3$
(b) Calculate the temperature if the gas is compressed to precisely half the volume at a gauge pressure of 1.00 atm.    $^{\circ} $ C

  What is the pressure inside a 35.0-L contain5m7x-l7 u 5nvf0ldruv er holding 105.0 kg of argon gas at 385 fuv lx 55rd -mn0l7v7uK?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg of qnxz0s2vw, a9 $O_2$ 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 lifd vy5xl:x qju.; -6jdxzvil o/)ot .f1t by heating the air inside the balloon, which makes it less dense than the air outside. Supposqv :5-zou/ xxfxld. l;j6doiy1jvt . )e 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 air oqewb3 7)a xrzd9 fy95at 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 ate.si 3 aeccl;2 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 chi:w :scoi fkqo-x/dxi- n9w* 6ild’s hand at sea level and 20.0 $^{\circ} $ C. When it reaches an altitude of 3000 m, where the temperature is 5.0 $^{\circ} $ C and the pressure is only 0.70 atm, how will its volume compare to that at sea level?    times the original volume

  Calculate the numberlyzgnioy8: *9r w4 * com)/nam of 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 moct.4q yhds r4t6ej- d*rp.9yjt jy +i1lecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (otzikb5kbdj2f zjqea-)j6,08 d1+u sa) moles,    $ \times10^{22 }$ moles and (b) molecules of water in all the Earth’s oceans. Assume water covers 75% of the Earth to an average depth of 3 km. $\approx$    $ \times10^{46 }$ molecules

  A cubic box of volume 5 l*6 zpjdvbx5-ev6ef: tg7 5ghf5xib4.1$ \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 7ube 5s+fir,x x) -yv64r t flclbop0*were also in the last breath Galileo took. [Hint: Assume the atmosphere is about 10 km high and of constanty v)+criultp0o5*-b7rfxbf4s 6, lxe density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of an w v2dsl9 te0j)zb t8a:oxygen molecule at STP?) 0:9ttadsvbjle8 2wz    $ \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 atoms61ri9x*ojiveofgb- + near the surface of the Sun at a temperature of ab+ i b6gjv-r xi1oo*f9eout 6000 K.    m/s

  By what factor will the rms speed of gas molecules9knmg7s r4 cqnwb /6+q increase if the temperature isw9 +kcqn7 64/rn gqbsm 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 hav(/xj g+q ai8wsed b/gpy5x7r5e the following speeds, given in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calculate the ib7a+sg edx5(/ g/wyrqx85 jprms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at 20.0 6 y)s4y.hoi rt$^{\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 held constantv+ eou a0.*m dil.f1jx, by what facfui d*x0vm1ja +o e..ltor does $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is given 3. lt5lrmp,k hby $v_{rms}$ = $\sqrt{3P\\rho}$ where P is the pressure in the gas, and $\rho$ is the gas density.

Show that for a mixture of two gases at the samscgs6,7s) ivgwwbi pv.k9v (, e temperature, the ratio of their rms speeds is equal to the inverse ratio of the square roots of their molecula wpcvis,9vvb)kg i 7s.6(wg s,r masses.

  What is the rms speed of nitrogen moleculegg 5jlc5a4z5 qs contained in an 8.5$-m^3$ volume at 2.1 atm if the total amount of nitrogen is 1300 mol?    m/s

  Calculate (a) the rms speed of an oxygen mgvc6lcb0u b83olecule 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 diwl,15blj m (jqstance between nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms spi dlr:-68hfri .oit(p eed of an amino acid whose molecular mass is 89 u in a lid 6 ri:-foitp h(ilr.8ving 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 wri3y5z6)z2cdn kn * zp66nnwj gytten 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:hqlbcste , nn6k9p od4 q6.*eh z997j oashe6, $^{235}$U and $^{238}$U (the superscripts refer to their atomic mass), can be separated by a gas-diffusion process by combining them with fluorine to make the gaseous compound UF$_6$ Calculate the ratio of the rms speeds of these molecules for the two isotopes, at constant T.   

(a) At atmospheric pressure, in what phases )wp +nrwu6)utyi:v4+ddpl- x 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 5uliav qn93i 2(a) qlu3n29 iv5ia 90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humi7uppl5 yzvx(y)w 2f d9dity is 50% on a day when the tempera dp7yx)2vyu (f zp95lwture is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a hb8bcptr:o*: -y bb69 a +kyhsplace where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place m,cg7b2u.7iy0 a*r rex* rxodin the mountains is 0.72 atm, estimate the tempera70rdrb2a.oce gxr* *y7x ,m uiture at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of6oa4vbys/p;l water is 530 Pa and the relative humi/ lpbas yv6o4;dity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day mli o)07)zo wbm )qut3when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cooker if the 75g20lb ubgjae iok* 1o0, ddfwater is boiling at a kgo010ea 5id2u, g7folb jb*dtemperature of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a0 x7w6hkhbb fp *jwa7 k2q:y0o room 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 poi;ppqkr ay; f27nt 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 2 7sae jb kdejpff--i1vvtb1-b* k: 4kmolecule (see Table 13–4) to diffuse a distancebk1-7ks d2p-if:tb1 baj *vf e-jkev4 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 dzs q p6u1j+f0q go4z5+ 6hktwto the interior through tiny tubes called tracheae. An average trachea is about 2 mm logd q51 zw4pju+ 0fk 6oqhtzs+6ng and has cross-sectional area of $ 2\times10^{-9 } m^2$ Assuming the concentration of oxygen inside is half what it is outside in the atmosphere,
(a) show that the concentration of oxygen in the air (assume 21% is oxygen) at 20$^{\circ} $ C is about 8.7 mol/$m^3$ then $\approx$    mol/$m^3$(Round to one decimal places)
(b) calculate the diffusion rate J,    $ \times10^{-11 }$ mol/s
(c) estimate the average time for a molecule to diffuse in. Assume the diffusion constant is $ 1\times10^{-5 } m^2/s$    s

  A precise steel tape measure has been calibrated aijx 4a5w0a ug7.qi*tc 1f qnl*t 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 measure7p5 b wdn ctnke8dt+3; has been calibrated at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A Pyrex measuring cup was calibrated at normal room temperature. How muct :fk;sn)o8d ch error will be made in a recipe calling for 300 mL of cool water, if the w od8):fckns;t ater 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 gay ovr:, tk-l2os cylinder is initially 28 atm. After many balloonr l-v:, to2okys have been blown up, the gauge pressure 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 length*c82p-j fq ipm9rspoa;7 2rhh 6.5 m, width 3.1 m, and height 2.5 m. Assume the temperature isj-f*h2a9 sq8o7c 2prir;pp hm 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is0bj e0dls eo9 in 0 zjj19x86wfy88jjved8i y7 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 techniques j+b2n mjqx0zp.cu2 wegf-w: 3-bwd)kis aboutn-m+p0):2 dwz3 2.b wwgcfb xueq-jkj $10^{-12} N/m^2$ 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 ohpu91tucp2 qofu22 7 full capacity of 5.5 L when 10 m below the surface, to what volume would his lungs expand if9otf u1 och2pu 27uqp2 he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning mi;poy+l 8ue9y.awj 7 sb)j/hfrom the Moon enters Earth’s atmosphere at a speed of about 40,000 km/h Molecules (assume nitrogen/9ha sim8;wy eujb7o.l+pyj )) striking the nose of the vehicle with this speed correspond to what temperature? (Because of this high temperature, the nose of a space vehicle must be made of special materials; indeed, part of it does vaporize, and this is seen as a bright blaze upon reentry.)    K

  The temperature of an k..e:h6 vaiq cideal 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 77x )tg6r uu*hj-gj4b gv/8k3cg 0m$^2$ (a) What is the total mass of air inside the house at 20$^{\circ} $C?    kg
(b) If the temperature drops to -10$^{\circ} $C what mass of air enters or leaves the house?    kg

  From the known value of atmospheric pressure at the surface of the Earth,dy;l/)crrc yu7( ri)h estimate th y7u(lc d ;hr)/ryrci)e total number of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contained in a 7+)ry 75mtm2 wg+qitkhu z i2/b.6$-m^3$ volume at 4.2 atm if the total amount of nitrogen is 1800 mol?    m/s

  A standard cylinder of oxygen1k pun3sfc+p wt(zt*. 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 atm(1+ nptwzkcp. s fut*3ospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of -:hc -9ellrnoliquid 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 gasol*y 3loc1mmrl h3 5uvl6yd+7c.3vvdn zrb40 boine at 0$^{\circ} $C is 0.68$ \times10^{3 }kg/m^3$ What is the density on a hot day, when the temperature is 38$^{\circ} $C?    kg/$m^3$
What is the percentage change?    %

  If a steel band were to fit snugly around the Earth’s b d.(;i)er*olicjze8 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 o nivp9jio7z x/(*ek bp;4 g;cwnto a glass jar at 20$^{\circ} $C. To help open the jar, it can be placed into a bath of hot water. After this treatment, the temperatures of the lid and the jar are both 60$^{\circ} $C. The inside diameter of the lid is 8.0 cm at 20$^{\circ} $C. Find the size of the gap (difference in radius) that develops by this procedure.    cm

  The first length standard, adopted iu, ygo4jhs +o*n 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 pressura 9 *xo oa*rf.ho/bx+0bocl+re 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 5:r2ebgf0ntyw jv z6e/t +r- l6t)arb$ 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 lidro4m+grum+/ ebxqw):q h) mt8bg,fy49 qe 7qq is suspended against gravity by tennis balls thrown vertically upward at it. How many tennis balls per second must rebound from the lid elastgq,f:roeqmwy)/q eg8qm+u 4) rbh q+x4bt 97mically, assuming they have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a yvw.,m79gk sc 3.00-cm-diameter (spherical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the air behcm7vsykg ,.w9 aves 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 followin20m e;hi9hm kzg two days: zh; 9 mk02mhie
(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 differ lmpwq,o-,e0 cence in the density of iron at STP, and when it is a solid deep in ,lew-,mop 0cqthe 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 to show that, for an ideal gas at constant pressure, tqoeg23s 5mj:k*iw lz5he coefficient of volume ez3le:*gqksiw5 mo2j 5xpansion 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 preve37 r 1ib9pgz rfeq-.gent rot and mildew. If the bfr qg gpe3-e9.rz 1i7cellar 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