Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodic ta3t .fq 6sdh p q/onn1tbz7ffc)8g;h.bble or Appendix3 f;to 7t/61pg)hszqqfb8 f.b.nchdn B.

Name several properties of materials that could be exploite8u7yh4-gs+3ns zxh eid to make a thermometzs i73 hxg8hneu4s-y+ er.

Which is larger, 1 C cg62od oam,c: mk d1y)$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilib yx mrbtd4zs 00h5z98z 56dlojrium with system B, but B is not in thermal equilibrium with system C, what can you s4 oh0ldsz5dzmbt r8y059 jx 6zay about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to a strfr89o*x k6mdz- )hassip of iron. When heated, the strip will bend. Which metal will be on the outside of the curve?r-mhaokz) x8 *s6dfs9 [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 1uzyuvg5a3v0 linear expansion $\alpha$ are $(C?)^{-1}$ and there is no mention of a length unit such as meters. Would the expansion coefficient change if we used feet or millimeters instead of meters? Explain.

Figure 13–27 shows a diagram of a simple thermostat used to control a furnacd7 hh5kn8g. rce (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 electricik8rc 7dh 5ng.hty 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 a;n3rd; d.skg / wsiorfn3 p92have a section in the shape of a U. Whd fa;o 3/npir293s sw;k.rd gny?

A flat, uniform cylinder of lea4 3mc:15 bvves yanu;wd 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 fanxc,k2q6b2x+i w b.r irst placed in a hot tub of water, the mercury initiaqb, c62 n xw.2kia+rbxlly descends a bit and then rises. Explain.

A glass container may break if one part of it is heated or cooled more rapb)c3,tf,gp(stdsf+/q su rh6 idly than adjacent parts. Expl tbs6 cs/,f+ gruds(t p3q)f,hain.

The principal virtue of Pyrex glass is that i t vih)0s tc.o5t;xrlbg p0;r+ts coefficient of linear expansion is much smaller thcpt t0g); ixsor 5+ th0bv;rl.an that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurate at 20 8nfbz co w4ky r,t+7eplz:0p6$^{\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 cc4 4 gk5w ez v+gxkdl;k5cv:q.ause its bottom and top to bulge so badly the can will not stand up5xdvcck zql v 5:.ek;g4wk4 g+. What has happened?

When a gas is rapidly compressed (say, b*ls1 e7 lo)uy5yvib+k y 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 tolky1ib vlu*e yo)+57 s the momentum of molecules when they strike the moving piston.

Will the buoyant force on an aluminuws)t (b0)t* yd+ciu smm sphere submerged in water increase or decreas 0mtby)(usdtc+ * i)wse if the temperature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from6v vb9ocz i-sh.7ecqezv(l.0 kinetic theory and the relation between average kinetic energy and theov6 v7l9v0c.eeb.h( z -s qzci absolute temperature.

Explain in words how Gay-Lsh )ez(c9m(rcussac’s law follows from kinetic theory.

As you go higher in the Earth’s atmosphere, the ratjnj9+8mk cf /k v2f9wiio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed an objechp7.wpm: /nh cf/f :twt must have to leave the Earth and never return. The escape velocity for the Moon is about one-fifth what it is for the Earth due to the Moon’s smaller mass. Explm/h./pp wt7nfh:fw:c ain why the Moon has practically no atmosphere.

Alcohol evaporates morq tuaa)-ycp59e quickly than water at room temperature. What can you infer about the molecular 9yt 5upa-aq c)properties of one relative to the other?

Explain why a hot humid day is far more uncomfortable than a hotjhyfl7 q:1dlhidz .4hp 69za2 dry day at the same7phlz.a hjyqd1i624z9 dh:lf temperature.

Is it possible to boil water at rt2e;a ,f:ncl room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air 8:mqgwnn 2 i4tz ym,-p azya5)temperature is the same but the humidity is different. Which is more dense, the dry air or 8y 4 5a q)t2 zgy-iwam:mnpn,zthe humid air at the same T? Explain.

Explain why it is dangerous to open the radiator cm .w6m db 23.geszal.map of an overheated automobile enginag2m.bm l6s3 e.wzmd.e.

Why does exhaled air appear as a little white clittnd9 r,660lg gb1ehoud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram copper peu8vh/hob) 5u tqp +v2 t(xeelu.,-sdhnny?   $ \times10^{22}$ atoms of Cu

  How does the number of -hdk 86rvr eg/;kd: comh,a .ratoms in a 26.5-gram gold ring compare to the number in a silver ring of the same ma/8kvdor :;.h,ercgkmd a6- rh ss?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this on ther/ :*xq -jk. vmkkgra; Celsius scale?kka/jqv:-g r*rk;x.m   $^{\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 lowess ts;dt).7 nu *jo:atlt 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 73ek+ 3 y qs93tv8 o0lvasiemralcohol column has length 11.82 cm at 0.0ylv o3ik379m8 s+ tesqa v3re0 $^{\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 sql. /bex/6c1wsrl. k ulabs 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 approximah* n uptkw xp0a;)utvj1(az+xaw 2h1,tely 300 m tall. Estimate how much its height changes between July (average temperature of 25°C) and Jut a;12u,z *+hkhnx1 a)awtp (vjwp x0anuary (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 rivety: gy2sz9tojsx, j /s6 hole are often used and the rivet is cooled (usually in dry ice) before it is placed in the hole. A steel rivet 1.8sg :29s,o6y j/zj sxyt71 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 atsr76b fzhi7 +art;ph7mhsd6 :q4k md8 4 $^{\circ} $ C is $ 1\times10^{3 }kg/m^3$ What is water’s density at 94 $^{\circ} $ C?    kg/$m^3$

  A quartz sphere is 8.75 cm in diameter. What will be its change in volu2jexj9f qp95 bme if it is hee529 qxjp fj9bated from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is e ek vfi:e4amc17qn4pj; * 4wtfilled to the 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 fz rk jhk +3t;hf2fm1:water at 20 $^{\circ} $ C completely fills a container to the brim. When the container and the water are heated to 60 $^{\circ} $ C, 0.35 g of water is lost. (a) What is the coefficient of volume expansion of the container?    $ \times10^{-5 }$ /$C^0$(b) What is the most likely material of the container? The density of water at 60°C is 0.98324g/ml.

  (a) A brass plug is to be placed in a rp0r+ft65vr l3m y dlsp;ormj7y2j ug9wfc(5 0ing 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 a long, narrow vessel so it can expand in essential020ao*akr lgg f/brcxgn7 3y. ly one direction only, show that the effective coefficient of linear expansion is approximately equkla.g*cr3y0agf rbo 2gn70/ xal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the de/r1q onz t bn.sk3x:g*nsity $\rho$ 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 platr0hhsa g4 68the of length l and width w has coefficient of linear ex hath0g8s4hr6pansion $\alpha$ 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 isokn1uyf +jatje i5:g, .tropic 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 keypqsd./k6kmg kh s0a/5em+m4eps perfect time at 1 m4hks mm.ka/k 5spe/gdq0+ y67 $^{\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 mm. The f 0x :xwnkq2d/bulb has a volume owx xqk:2fn0 /df 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 tn w 8vyzq b6k/6cdb4ac4j+4hwheel of radius 0.41 m is rotating about its axle on frictionless bearings with angular vew44n vyj6catkb4d +z q6ch/8 blocity $\omega$ = 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 *fr*zuu dpa6+ when at 15°C. How much stress is required to keep it at this length if the temperature increasep *a6*rf+zu uds to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-bea;*k9qc8 xzdll m 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 134.1 8 rzu.ck.ip c*u:s(q/hr- nlf22 cm at 20$^{\circ} $ C is to be enclosed by an iron band. The circular band has an inside diameter of 134.110 cm at 20$^{\circ} $ C. It is 7.4 cm wide and 0.65 cm thick.
(a) To what temperature must the band be heated so that it will fit over the barrel? $\approx$   $^{\circ} $ C(Round to the nearest integer)
(b) What will be the tension in the band when it cools to 20$^{\circ} $ C?    N

  What are the following temperatures on the Kelvin scal-y qv9bc7dd3te:
(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 temperakxf1hzn 95h-plamly 34/ z8 hature on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the i brpjcna ce( )qr-e5c/ fa2h1;nterior of the Earth and Sun are about 4000$^{\circ} $ C and $ \times10^{6 }$ $^{\circ} $ C respectively.
(a) What are these temperatures in kelvins?    K    $ \times10^{ 6}$K
(b) What percent error is made in each case if a person forgets to change $^{\circ} $ C to K? $\approx$    %(Round to the nearest integer) $\approx$    %(Round to three decimal places)

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

  In an internal combustion engine, air at atmospheric pressure and a tempewqb.5rz6uh(uz51 wuz3t)lv /)bpu xorature 6u)u wpw5z(3qor) 1 th uzzv/x b5ul.bof 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 yv uu9.gw9c6bp9 lsyd9lh0) p at STP using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of nitrieoqg0( xk ;6/v7 qdm-jwk sx)ogen ($N_2$) 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 STPu;op15nyuq fe046qz xn1 r:k;o pvl2v 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 ga ngdrf (7ppw9/s 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 container holdino0m2it3 6 gmi5as6gudg 105.0 kg of argon gas at 38smut3iga0d 26g moi 565 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0u pdcr; /x(b /eli:y1e kg of $O_2$ gas at a gauge pressure of 8.70 atm. If the oxygen is replaced by helium, how many kilograms of the latter will be needed to produce a gauge pressure of 7.00 atm?    kg He

  A hot-air balloon achieves its buoyant lift by heating the airslb,t 4q)6ceo inside the balloon, which makes it le o)c,e6b 4qltsss dense than the air outside. 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 airc d:t34m( 78s swpzo6 4g(ykey4hq6ouka +v pt 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 l l u8*c2-osjj+e;c pnat 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 atgi1c5gubr74:0tyh1ds sbzd + 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 number of uv8d,4,qf wpxkvfg* a5 9mrf,o kg4o0 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? Ho4-stxelzwtlg y 9i :+/w many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) moa-je,t7nq .zxr.u8o3 3ns5qa;mqme nles,    $ \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 n+ db wsu92kh,hv fmh0a c6.4y5.1$ \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 th 8vev-zknz f. )2y5kyiat were also in the last breath Galileo took. [Hint: Assume the atmospherzke-ky5vvy zn 8 f2.i)e is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of69qkj /sveld) an oxygen molecule at STP? )s 9e6qjv lkd/   $ \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 nel :sxw vzwm.j fid;t 69j8f:a-ar the surface of the Sun at a temperature of aboutfai: -jljxz:sdvw. mwt;98 6 f 6000 K.    m/s

  By what factor will the rms speed of gas molecu;in7prxi:bp /cme3k 0les increase if the temperature is increased fc m in3ep:r;7k0x pb/irom 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 sp4-m(gkvz6nckjly 6v0 nz ,)cy eeds, given in units of km/s: 6, 2, 4, 6, 0, 4, mzc,4 cjv6nnk k)zyl- (g06vy1, 8, 5, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules ip-wqw6 vq h6*li)e/s qn a gas at 20.0 $^{\circ} $ C is to be increased by 1.0%. To what temperature must it be raised?    $^{\circ} $ C

  If the pressure of ae+ep:qr56+nex b tx.h u7gj s- gas is doubled while its volume is held constant, by what factorx ux7+qpe : bgej.h-+netsr5 6 does $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is gi e6ce)eo h)5woyan;4iven 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 temperature, the ratiou/73ei3i / *lvcxne kf of their rms speeds is equal to the inverse ratio of the square roots of their molecular m3n/7 ulcxe /i3e*ki fvasses.

  What is the rms speed of nitrogen molecules contained in an byl*lecq160 uw9h q4 x8.5$-m^3$ volume at 2.1 atm if the total amount of nitrogen is 1300 mol?    m/s

  Calculate (a) the rms speed of an oxygen mo7ksf* d hkm qh6vms70k(tldk6 f(l0;llecule 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*n v7fee5na o( at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms kuc4xb 1-) lev.:qg( naq q+jvspeed of an amino acid whose molecular mass is 89 u in a living cell at nqx a+bk.14cvqj v(uelq:g) -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 written P = tzc/c /doaxv b. )al: m;tp+c:$\frac(1)(3)\rho v^2$ where $\rho$ is the density of the gas and v is the rms speed of the molecules.

  The two isotopes of uranium,idkc ( has,q; 2q3hmv9 $^{235}$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 c8m-o ;-nq:;or hs lcvran $CO_2$ 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 atmmw ahpt5+ tj7+ and the temperature is (a) 7t+a5+ph jmtw90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (appud:)d 28ekxtb-vg8 h hag8 .stroximately) if the humidity is 50% on a day when the tempgehg a:2-b )x8shdt t8vd.8ukerature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water boill.a m)rody0q50 *yuqcs at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is 0.72 atmkkcp6u( -uss 0, estimate the temperatur- s( ucpuk0sk6e at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of water is 530 Pa an 00lhtd8 yqpl;:dx7dgd the d 8hqx7:;ldgylp 00tdrelative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a dak0mle t--y-5uzprt2p4*b rtdy when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cooker y .ahn y2l-,qcif the water is boiling at a tempera, .2ylynha c-qture of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a 3- t6 3 qfocsammvl()croom 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 dgi uyw foy 9sd9684e55 $^{\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 glycinugvr 72;6of1d j40id8nheavz e molecule (see Table 13–4) to diffuse a distance of 0doavg8 uz6ern 27d 4iv;f 1jh15 $\mu m$ 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 thbw2mbm o253 hwe interior through tiny tubes called tracheaew3 w5h 2m2bobm. 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 hasr7cp6nw/a-jgu4*o c qy (xtngcy5 n9+ 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 o)m+2l d2nlc(j +g jz guy/;mzhas 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 d3qxoz ;y/*vgj ju i94much error will be made in a recipe calling for 300 mL of cool water, if the water and the cup are hot, at 804 /j *9gqz;uojxd 3viy$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in a helium gas cylinder is initially 28 atm. After maepd1kl 2 tc56(t;s/jwkki/ c +wtyg)h ny balloons have been blown up, the gauge pressure 2 lth( k)kdc/;/tt5k e+ipsww6 yjgc1has decreased to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air mo a w (-gi)9cifadhk5p+lecules in a room of length 6.5 m, width 3.1 m, and height 2.5 m. Assume the temperature is 22-aiw) kf5 hgpa+c9id($^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of mattewa xfq43;i ;sl.m:4 tzml 9dbor 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 available ,ckn;p)if(g c.6 ojeuemj2qdf 1-/gt vacuum techniques is about ,c;c ept/j ok2e q g1 m()ug6.-nidjff$10^{-12} N/m^2$ 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 hojc hw6t/-pz1 o(/gy yis lungs to full capacity of 5.5 L when 10 m below the surface, to what volume would his lungs expand if he quickly rose g6yh/ o/o - pj(c1tzywto the surface? Is this advisable?    L

  A space vehicle returning from the Moon ent2k o(i/d*;ml - qutspa0k4 nyvers 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 matermkpv0ayq2l; td*-( /o i4sknuials; indeed, part of it does vaporize, and this is seen as a bright blaze upon reentry.)    K

  The temperature of an ideal gas is * .n gs - n.t4sx1p)psu:ezcitincreased 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 7 y/4)w6quuz ya/6wnkd70m$^2$ (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 ttuqq :9y6rkex 6(n:mche surface of the Earth, estimate the eyqu(6tm :x nc6rk :9qtotal number of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed 7dj(1r)brxnp m y8*zz of nitrogen molecules 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 hospitalb- 4vd*mra bi /abb cyz9b*-b/ has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if yb-acz b**/m49b - vrbbb dia/the flow rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of3u8v5pmttk 2y );3mrtv kv qg) 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 gasoli3atz3h 7e:k it 3c0wmzne 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 equat6ef/iod8f8c c or 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 tightl.1snlu4jmi3 wy onto a glass jar at 20$^{\circ} $C. To help open the jar, it can be placed into a bath of hot water. After this treatment, the temperatures of the lid and the jar are both 60$^{\circ} $C. The inside diameter of the lid is 8.0 cm at 20$^{\circ} $C. Find the size of the gap (difference in radius) that develops by this procedure.    cm

  The first length standarm4pts sxhn,s h-r2/- rd, adopted in the 18$^{th}$ century, was a platinum bar with two very fine marks separated by what was defined to be exactly 1 m. If this standard bar was to be accurate to within $\pm1.0 \mu m$ how carefully would the trustees have needed to control the temperature? The coefficient of linear expansion for platinum is $ 9\times10^{ -6}C/^{-1}$. $\pm$ =    C$^{\circ} $

  A scuba tank, when fully charged, has a pressure of 195 at- h8j nktbfl7ipr z.7(m 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 5gr -j z5ru4a8;wv pxqthe Earth is $ 1.12\times10^{4 } m/s$ so a gas molecule travelling away from Earth near the outer boundary of the Earth’s atmosphere would, at this speed, be able to escape from the Earth’s gravitational field. At what temperature is the average speed of
(a) oxygen molecules,    $ \times10^{5 }$K
(b) helium atoms equal to $ 1.12\times10^{4 } m/s$    $ \times10^{4}$K
(c) Can you see why our atmosphere contains oxygen but not helium?

  A 1.0-kg trash-can lid is suspended against gd ufwe a2qdh;6cgnla, +;i. g4ravity by tennis balls thrown vertically upward at it. How many u 46dc , w2;;iqlgenda+fg. ahtennis balls per second must rebound from the lid elastically, assuming they have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter (spherical) bubble of air from a depthaq1vlwljt n1 a ad ():9na 6f*rx26ejo of 14.0 m in a lake. Assume the tempe1xtoq*l1 )vj d2 6( 9n6ajelwr:faana rature is constant 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 a:yx;h w( ,u)v05pr q/xwa xuyvir on the following two days: w;, :pv0 xuyhx v/wx(5y)rqau
(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 densit )o82ciw ,ute0gwv*+ jk d9 *nu;dznlzy of iron at STP, and when it is a solid det*luk ,*n92 du8+ 0i zvc)oegw;zjwd nep 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 to show that, for an 10( kmdly7tdj ideal gas at constant pressure, the coefficient of volume expansion is equal tojdy1d k(tm0l 7 $\beta$ = 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 deh8dtq. ixevs(5 ace54dumidify their cellars to prevent rot and mildew. If the cellar 4d8ds 5 .t5xiveaceq( 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