Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodic ta+ orsd1oyy6zjtl o6 b.d)kr,8ble or Appendix B.) lok 6+rs.yr,z o1tdd8oy6jb

Name several properties of materials that could be exploited to make a th fmh4:vt2y7qsk c ,z1qermometeqh yq 1k2scvt4,m7:f zr.

Which is larger, 1 C5 /i c2 +0o-ces-jkoutmfyg/r $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium wit ,c(zl ngyb/bsn8 rkl;2qu5,oh system B, but B is not in thermal equilibrium with system C, what can you say abo/qn;ubk(zl,r,82byol5 scngut the temperatures of A, B, and C?

A flat bimetallic strip c /v juz1tpok:t4bfwhy6me2*1gdp 0c 9onsists of aluminum riveted to a strip of iron. When heated, the strip will bend. Which metal will be on the outside of the curve? [Hint: See Table 13–1dbhgky:u/ t6* t9m ce014j wp2fvpo 1z.] 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 coefficienmjwf a/*w3w*a t of linear expansion $\alpha$ are $(C?)^{-1}$ and there is no mention of a length unit such as meters. Would the expansion coefficient change if we used feet or millimeters instead of meters? Explain.

Figure 13–27 shows a diagram of a simple thermostat used to cont.aferd6r19xc rol 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 electricity when it canedc6. f9x1rr a 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 fipqpku f n)ixk17b8fa1mh393exed at the ends often have a section in the shape of a U. Why?fepk7k1p9i 8fq1)ux n3m a h3b

A flat, uniform cylinder of lead floats in mercury at l99.gx+ytxfl 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 t :dowe 21r-zntub of water, the mercury initially descends a bit and then rises. Expla2rw-dzo 1ten :in.

A glass container may break if one part of it is r4x/1s) w*qm8 vpm(t9futrx nheated or cooled more rapidly than adjacent part r4 qmpsr9n1/)f( txw*um vxt8s. Explain.

The principal virtue of Pyrex glass is that its coefficient of linear expansio8hay -9a,s: jwv fzz-,zs*gpwn is much smalle,v zjas fyw *ga,phz8-zws9:- r than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, aclvim jj);v2n 0curate 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 sod07kiru9ex- jg 5oul. ka will cause its bottom and top to bulge so badly the can will not stand up. What has happe0l5gurk xij.u -o9k7ened?

When a gas is rapidly compressed (say, by pushinsz 85g8r temhjw f940gq-,xcg g 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 of molecules when they strike the movirheg4gq , 59zfgc m8jtxsw0 -8ng piston.

Will the buoyant force on an aluminum sphere subme: fxlvmpdz 7/7rged in water increase or decrease if the temperaturevm/ 7 7fzpld:x is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic thew 5szd50 ihg;s 56ofepory and the relation between average kinetic energy and5s5 izps605ed;gf who the absolute temperature.

Explain in words how Gay-Lussac’s rn.95 yw1cs ql6:cu melaw follows from kinetic theory.

As you go higher in the Ear 6-8 xzp 3xk: )3ar (q,usrk/l*yasnubv7jg hyth’s atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed an object must have h+i )dhji44hy 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. Explain why thdi4jhy)h4 + ihe Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at room temperature. Whomzw9p :hews82; x*ua,l d3ougldn93 at can you infer aboutnwxwo:e9 9dh ;llzu*ps2,au 3o8 m3dg the molecular properties of one relative to the other?

Explain why a hot humid day is far more uncomfortable than a hot drchd(6h eh 6vh, np7ch*y day at the same temperchh p hv,hce(6d*6 7nhature.

Is it possible to boil water at roza3q9 pcw )1knom temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the /y +q ldf7m7vfhumidity is different. Which is more dense, the dry air or the humid air at the same T? Expm7 +dq7 flfvy/lain.

Explain why it is dangerous to open the radiator capxg 1u9y/9 xocq of an overheated automobile/ 1x qx9ygc9ou engine.

Why does exhaled air appear as a little white cloud in the wlw p2xo;;a)3*k nw)m cq vypqmpce0 ,:inter (Fig. 13–28)?

  How many atoms are there 56vff6cuxh3fin a 3.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold gp .dn/0f fp5)zj1vujrzi//o ring compare to the number in a silver ring ri1g f)jz/ p.d0f5zjvun// opof the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this on the Celsius scal:.70 rxt 3(js4 b1lag 2qtbo r/reyiffgzho *,e?(jo:04gxrahg7i ro./b1 fts3elbz2 rf*t q,y   $^{\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 temperatures recorded are 136 7 jbn+k jj vhhjarg* ku)),.4b)ii3 ii$^{\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 cw p xwuyffz;rw-/ k6 +e/ckx.4m at 0.0c+ zx/rkf; w4-ky /p6ewx.uw f $^{\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 sl .;de0u+/hijwm j/xe qabs 12 m long (20 $^{\circ} $ C). How wide should the expansion cracks between the slabs be (at 20 $^{\circ} $ C) to prevent buckling if the range of temperature is -30 $^{\circ} $ C to +50 $^{\circ} $ C?    m

  Super Inva$^{TM}$, an alloy of iron and nickel, is a strong material with a very low coefficient of linear expansion [0.2$ \times10^{ -6}$(C?)$^{-1}$]
A 2.0-m-long tabletop made of this alloy is used for sensitive laser measurements where extremely high tolerances are required. How much will this table expand along its length if the temperature increases 5.0 $^{\circ} $ C? Compare to tabletops made of steel.   $ \times10^{-6 }$ m    $ \times10^{-4 }$ m

  The Eiffel Tower (Fig. 13–29) is built of wrought iron approximately 300rja lsuc;s6)h8h -ku: m tall. Estimate how much its height changes between July (average temperh6alhr sjsc:k-; u)8uature 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 than th 3 pcyh-3izz8ud numj17u1ze1e rivet hole are often used and the rivet is cooled (usually in dry ice) before iuuzd-z pj3ez81iu1 3h 1 c7mnyt is placed in the hole. A steel rivet 1.871 cm in diameter is to be placed in a hole 1.869 cm in diameter at 20 $^{\circ} $ C. To what temperature must the rivet be cooled if it is to fit in the hole?    $^{\circ} $ C

  The density of water at r2lpuejx /9u2fd esk sm2-q+*ped*h84 $^{\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*tb:sejx7y7yfybh4 3f hy*l rt 7 c:m6. What will be its change in volume if it is heated 7ebrjyct*4sfl67b 7xf*3:ytyh:m yh from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is fill6o o;gp ls+l-ged 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 wb0 gq2i sp)mpw 6mah..bw m(4uater 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 pln0) 8pzs2wnb maced 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 contaiv43: aekpa7ey zp 0c1pned in a 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 coefficient of volume exp4 pa1k3 ve7aycze :p0pansion $\beta$.

(a) Show that the change in o,vow ;; skxb1the density $\rho$ of a substance, when the temperature changes by $\Delta$T is given by $\rho$ = -$\beta$$\rho$$\Delta$T
(b) What is the fractional change in density of a lead sphere whose temperature decreases from 25 $^{\circ} $ C to -40 $^{\circ} $ C？

A uniform rectangular plate of length l and winjzkd*y 3 6ec1dth w has coefficient of linear expansioz*ndk yej6c 31n $\alpha$ 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 isotk4 g8 qzh87mkkropic 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 clocq j3ul( jdr8,qk is made of brass and keeps perfect time at 17 jj8q r3,uldq($^{\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. T7h0,l-q5zv/ pwuue rxhe bulb has a volume of75q0/,-plevz wuhxru 0.255 $cm^3$ How far will the thread of mercury move when the temperature changes from 11.5 $^{\circ} $ C to 33.0 $^{\circ} $ C? Take into account expansion of the Pyrex glass.    cm(b) Determine a formula for the length of the mercury column in terms of relevant variables. Ignore tube volume compared to bulb volume.

  A 23.4-kg solid aluminum cylindrical wheel of radius 0.41 m isrlx4e/)8s x bhyam a, -4skmq( rotating about its axle on friqhl 4(yam/x-,4b se) ks8r xmactionless 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 lenbw hdc 4s6ii wub.-tqe.* ag(0l e9sd6gth when at 15°C. How much stress is required to keep it at this length if the 9*6 cds6w4 (0 et iuw.-l.siagbbe dqhtemperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-bsvgc2tvs:5)3t0 4j pcyf g 2hleam 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 cm at - iedm ir6n.5,di) odm4 ly(gc20$^{\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 tempiy -dzgpnx :vo137m p*eratures on the Kelvin scale:
(a) 86$^{\circ} $ C,    K
(b) 78$^{\circ} $F,    K
(c) -100$^{\circ} $C    K
(d) 5500°C,    K
(e) -459$^{\circ} $F    K

  Absolute zero is what temperatur/3wgcm76e xgbfx1clg n e:v)*e on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Eardr1)8gnqa*brqj :;t e 7ab+(tb b1ida k/lc x/th 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 2 r4 m1je8qwekq dw))va temperature of 4k 1ee8vjqr d)2q)wm wabout 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 lua3 *jc jkc)g3o.v p2ue i:hnno:y-+caw.    kg/$m^3$

  A storage tank contains 21.69 ci m4w y)tzlk;cm01hwr47op kg 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 k+4 bw3 a+gkb)d o;rhw1gw4(myxhb x0 gg 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 heliumyiyb)ni ( 6.xe 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 container holding 105.0 kg of argon gas att4alom 9- nit/1s eh7m 38th9tne /7sm - 1almoi45 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg of fdov z) (a1 5xn89t8x soo:wpi5ra9vg$O_2$ 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 air inside the bac.ol +c5 uivkn48 hn/blloon, which makes it5chu 8.lvnb4ok+/c ni less 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 air 6u2 de s.0e 7mn(une5mge.uxv 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 18o cchjl 2x3,8iqa)jyp jk. w09*wmc)e.0 $^{\circ} $ C and an absolute pressure of 2.45 atm are compressed to 48.8 L and at the same time the temperature is raised to 50.0°C, what will the new pressure be?    atm

  A helium-filled balloon escapes a child’s hand at uv/yyb.2zo : wsea 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-lgv w9 i,d4 iq;vk,g5fftl 7k3tmjz sd 2j6i9ecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are thecyyzzp40u.hc9 q ;cm.re in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) moleqtj :4rei -s9hd 6o:bas,    $ \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 5wyx+ hkbau(,ztx7j t ( e4zgo) 6(ygq/.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 arf is 6 7xndq5qvw7x,v+e in each 2.0-L breath you inhale that were also in the last breath Galileo took. [Hint: Aif,56dxwq v x7v+ s7qnssume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energyty, jzp+* o-drkg*sb9 of an oxygen molecule at STP? jp,s 9zgd ky**o-tr b+   $ \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 heliumk hwta69c:z we2)usz 7 u 1ur,ujx9c6a atoms near the surface of the Sun at a temperature 9 : ca ctu6ua )s6jre9zz1k,uh2w7w xuof about 6000 K.    m/s

  By what factor will the rms speed of gas molecules incr*gj fy9s :j.obease if the temperature is increased fj* : 9goj.sybfrom 0 $^{\circ} $ C to 100 $^{\circ} $ C?   

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

  Twelve molecules have the following speeds, given in units o lk:8.pv utm(rljwo33gr oe1: pti6g,f km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calculate the rms speed. wr:lr:3 ,gv ipjl 6.tu(3goeo pk8 1mt$v_{rms}$ =    km/s

  The rms speed of molecules in a gas 8 ;dg)i t/zdzbat 20.0 $^{\circ} $ C is to be increased by 1.0%. To what temperature must it be raised?    $^{\circ} $ C

  If the pressure of a gas is doubled while its volume is held constant, by what f;*ez wdl.o.b qactor w* o;. lq.ebzddoes $v_{rms}$ change?   

Show that the rms speed of molecules in a y9 xo+fe( ezroke2if04, zn;xgas 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 twoe 4wgi( h l(puomv8+ jqp;:(j-6 ymkcw gases at the same temperature, the ratio of their rms speeds is equal to the inverse ratio of the square roots of their molecular masses+iyvjuj w(6 m(mcq;48p pgh-w(eolk:.

  What is the rms speem;tiydoy-t rmydl:6 8) wya17 d of nitrogen molecules 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 spnbmzm 3e2 h;xe)/aqkz l:p-v,eed of an oxygen molecule at 0 $^{\circ} $ C    m/s
(b) determine how many times per second it would move back and forth across a 7.0-m-long room on the average, assuming it made very few collisions with other molecules.    round trips per sec

  What is the average distance between nit t)tut h1kwz54rogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular masp u7i6) fdfu*bs is 89 u in a living cell at 37 fub u6i)*fd p7$^{\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 wrll 4sjam:,r.;*n x pnqitten 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 ust t8 wm zwh2dii:3f4*ranium, $^{235}$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 yj c:ao;0 m8r0qcbqh+ *arl+gwhat 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 atmxryv. cc f*.m5kpd0k opu4m9. and the temperature is (a) 9c4f9 m5* .m0uxv rko .c.kdpyp0 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidityk;l:fjs, z 7nq is 50% on a day when the te; lj:ns 7f,zkqmperature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure gm0de+asn.w(n e2 /wsqw i3:j at a place where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is 0.72 atm,pw( unn:rm7: y estimate the temu (:prn:w 7mynperature at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of wei( q)ft5pd0xn y6 1vfater is 530 Pa and fnfepq6dtiyx)1v 5(0 the relative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water ouuxd ar*f. f46lx)38ml3xsgon a day when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside af 3lq1;zdyhd9fm:m*a7 ,do + ws;(.c gkwdlxi pressure cooker if the water is boiling at a temperature of fw( d .9ok d1w zcg 7h;diqy3 f;aldmml+sx,:*120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room of volume 681qaujs0ao611 zcuts9 0$m^3$ at 25 $^{\circ} $ C is 80%, what mass of water can still evaporate from an open pan?    kg

  Air that is at its dewy(8c;byv k1 rq point of 5 $^{\circ} $ C is drawn into a building where it is heated to 25. What will be the relative humidity at this temperature? Assume constant pressure of 1.0 atm. Take into account the expansion of the air.    %

  Estimate the time needed for a glycine molecule (see 5netg11b 4mi00 vne moTable 13–4) to diffuse a di ie1n45 g1onmt 0e0mbvstance 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 froml3 4n,*ggrut9d7omf o the surface of insects to the interior through tiny tubes called tracheae. An average trachea is about 2 mm long and hu,m4ltgo7r n9*o3d gf as 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 at 20;yw) h v;bhz;noda. s -jc;+ao$^{\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 m8zo )crw8 nynx*s ,r-measure 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 much sis7;o,s dqf:error will be made in a recipe calling for 300 mL of coolqs: sdso f,;i7 water, if the water and the cup are hot, at 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in a helium gas cylinder is)g iwk bgu64+e4.mr7pgy+ tv q initially 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fractior6qvgk w)4 gpg4uytie+m7+ . bn of the original gas remains in the cylinder?   

  Estimate the number of air moe5mqb q 8,y.w /0cztbora7r n(lecules in a room of length 6.5 m, width 3.1 m, and height 2.5 m. Assume the tempr 705mb8etco(yb, q.z/ qarwn erature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of mdt80 s,on;nghhej:oc6 4x *h qatter 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 attainablp81td/t. l-24ks2tvz tx-gvg1 lbk axe using the best available vacuum techniques is about t x-vp gka. l/14v2xtd2kz- 8sbttl 1g$10^{-12} N/m^2$ At such a pressure, how many molecules are there per $cm^3$ at 0$^{\circ} $C?    $\frac{molecules}{cm^3}$

  If a scuba diver fills his lungs to full capacity of 5.5 L when 10 m below the s q *bthn+pehxzl5r(/;urface, to what volume would his lungs expa5/ n;*zpbhqrte+ hl x(nd if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moon ente,7b -ewh9ytx -2tcs zzrs Earth’s atmosphere at a speed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this spee 9ywbe7,z chx2-t-zstd 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 ideal gas is increase 5jjwgg9g95ag0b;ur xy .)tb4crsj- bd 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 sa/ca1y0xgpr ;fwv9u4zyb lh5(s22 y of 770m$^2$ (a) What is the total mass of air inside the house at 20$^{\circ} $C?    kg
(b) If the temperature drops to -10$^{\circ} $C what mass of air enters or leaves the house?    kg

  From the known value of atmospheric pressure at the surface of the b hywgrh 47-+uEarth, estimate the total number of air moleculeghy w +hur4-b7s in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules conta0wlqaebd **g*ined in a 7.6$-m^3$ volume at 4.2 atm if the total amount of nitrogen is 1800 mol?    m/s

  A standard cylinder of oxygen used in a hospital ba) mlvem m0a(9 qnng67my.v2has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow ratevn0(mlmm9 g y . 7b)ve6maqn2a, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liquid mu (huwj6 ve.czw+b t1 5o9r)xgercury 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 gasolinwe*t)d:gak k 0)dnl)ce 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 b,c2 9 fssku(oEarth’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 tightly6sk ap 6:n2bx c8mgmmb3s 5io,1 oyhw7 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 standa 8cql1 qmijq17rd, 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, ha(x c22oe-wk ggs a pressure of 195 atm at 20$^{\circ} $C. The volume of the tank is 11.3 L.
(a) What would the volume of the air be at 1.00 atm and at the same temperature?    L
(b) Before entering the water, a person consumes 2.0 L of air in each breath, and breathes 12 times a minute. At this rate, how long would the tank last?    min
(c) At a depth of 20.0 m of sea water and temperature of 10$^{\circ} $C, how long would the same tank last assuming the breathing rate does not change?    min

  The escape speed from the Eartu(aeqi59m :, dzria0o h 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 agaqbp b0b;nr*4u inst gravity by tennis balls thrown vertically upward at it. How many tennis balls per second must rebound from the lid elaru4p0n*qb bb ;stically, 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 depthw ebw9a43n1hdp vl t.* of 14.0 m in a lake. Assume the temp3he 9p*lwn1. tw a4bdverature 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 wate:hj zz2n5hc5c r5/k k+gf.nnfr vapor pressure in the air on the following two days: z:ff.h n 2k 5nzh/rjckg5n+5c
(a) a hot summer day, with the temperature 30$^{\circ} $C and the relative humidity at 40%;    Pa
(b) a cold winter day, with the temperature 5$^{\circ} $C and the relative humidity at 80%.    Pa

  A sauna has 7$m^3$ of air volume, and the temperature is 90$^{\circ} $C. The air is perfectly dry. How much water (in kg) should be evaporated if we want to increase the relative humidity from 0% to 10%? (See Table 13–3.)    kg

  Estimate the percent difference in the density of iron at STP, and wheniu-0ah el5j+. (cwui n it is a solid deep in the Earth where the temperature is 20+u iwa.ihecn j(0 l5u-00$^{\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 zfx1 w//0j(tuvylmwk96 /hiu an ideal gas at constant pressure, the coefficient offyw1lvhztuk/x9 (j u/m6 i/w 0 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.