Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodic tabl3np wc;0ilb idj5x9 i1e or i5 d9;ji0n3xpwcb il1 Appendix B.

Name several properties of materials that could be exploited to make a thermomdu 2f5lob,if8 eter. ifu,l28o5fdb

Which is larger, 1 C :w,q afwp r.0yc) ylg4$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium witn5zf p7/ixg+th system B, but B is not in thermal equilibrium with system C, what can you say about the tpn 7xit5 f/z+gemperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to a strip88euaztuv-1fvn; 7 i6m m khg1 of iron. When heated, the strip will bend. Which metal will be on the outside of the curve? [Hint: See Table 13–1.eu8 hn7m6v18- v ug1k ati;fmz] 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 expansion +pdntx+ ml,jxh7 -k,f $\alpha$ 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 user zm, 3t 4x.64w(gozf dp;rvwhd to control a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch is a glass vessel containing liquid mercury that conducts electricity when it can flow to touch both x4dgtwmvzfz, rh( ;.r3o6wp 4 contact wires. Explain how this device controls the furnace and how it can be set at different temperatures.

Long steam pipes that are fixex77vxblda 7 3 e vf6v8ge5mfc3d at the ends often have a section in the shape of a Uvvfb367l57 xm dg8xeve7ca 3f. Why?

A flat, uniform cylinder of leadc(i kp8 (k+s6:t ck s9exqt8.a;je2zth; wyhm 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 of watec. y6/;uwovl+gdvdn . r, the mercury initially descends a bit and then rises. .ygco .dl6 uv/dv +n;wExplain.

A glass container may break if one part of o+3l/ioxc y7f it is heated or cooled more rapidly than adjac/fc+l3oyxo 7ient parts. Explain.

The principal virtue of Pyrex gi*:q kb8 )ivtvlass is that its coefficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the it*8vkib:q ) ivncreased heat resistance of Pyrex.

Will a grandfather clock, accurate a4z),nate uf9bwgc2y0h1 ucr-t 20 $^{\circ} $ C, run fast or slow on a hot day (30 $^{\circ} $ C)? Explain. The clock uses a pendulum supported on a long, thin brass rod.

Freezing a can of soda will cause its bottom and top to bulge so badlfddg)4zy,i1 ;n exux (y the can will not stand up gz;e yx(4 ,fn1dd)xiu. What has happened?

When a gas is rapidly cou7xc*zl,*o sjmpressed (say, by pushing down a piston), its temperature increases. When a gas expands against a piston, it cools. Explain these changes* sx,co7ujlz* in temperature using the kinetic theory, in particular noting what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force on an aluminum sphere submerged in wn3o7(y nkwo3,v 0jv rsater increase or decrease if the temperature is is0v nr,o7yo vk3(wnj3ncreased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law m n;s 340u3uots3hazx follows from kinetic theory and the relation between average kinetic energy and the absolute temperat a34usts3o0 nzhm;3ux ure.

Explain in words hownwl g92go 5a7i Gay-Lussac’s law follows from kinetic theory.

As you go higher in the Earth’s atmosph)ukea :o0; fetmnun4.ere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum spsyt++8kan)pl(l2g xjeed an object must have to leave the Earth and never returny82latjxns k pl g(++). The escape velocity for the Moon is about one-fifth what it is for the Earth due to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quicw7ixk2y ( fukxht;s*3kly than water at room temperature. What can you infer abouk;3kx*uyhfs2xt (w7 it the molecular properties of one relative to the other?

Explain why a hot humid day is far more up;ild ebu2dulv.(qhynn + -yi)g7k(* ncomfortable than a hot dry day at the samnli( + yy)v dd(u*. lg7-2qe;hbnupkie temperature.

Is it possible to bobe ay-s3r.:e r 5l7hxnil water at room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the humidi1zpjjp+)o43u1xlph lx j5vh +ty is different. Wl+13jpx)pj l4 uxvo5+ jphh1z hich is more dense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerous to ope(q: bz+olf;w 7kfpbc6n the radiator cap of an overheated automobile 6 o;qcf+l kpwf:(7z bbengine.

Why does exhaled air appear as a little white cloud in the winter (Fxa9d oz;b0 q e,xrsh96ycj7i/ig. 13–28)?

  How many atoms are there nm)*qu,4 hfbz in a 3.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold rsv8p 0;2 pa3 vp*aipu*pzgl 5swxxe6;ing compare to the number in a silver ring of the avwvp0 5p *px;zsal 8;sup 2pxge *3i6same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to bel/dl rk 2spuuo0;lz73)5el wh 68°F. What is this on the Celsius scale?d2lz ;s) pl/le0u3r7k5ulhw o    $^{\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 temperaturezn3ezxoqh 4y tj23 79us 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 lengthe+sga (z5xdb 03)k b wanc7sh4 11.82 cm at 0.0k( bnghcbwa3x7z 5) 4a+ed0s s $^{\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 bu t g6(hc: z7 1db9t8olqs p:xets6lqr(ilt 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 wrougb;4t m4nnr v5ght iron approximately 300 m tall. Estimate how much its height changes b4 5t4v bgr;nmnetween July (average 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 than the rivet hole are on .gwq7vnqa7- ften used and the rivet is cooled (usually in dry ice) before it is placed in the ho nag.7vn-qw7qle. 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 i+-lz (k j m:.qp)ztjf5ko.faat 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 c oa0fwv6dorwr.- 6t2 e;or8kzm in diameter. What will be its change in volume if it is heate8od62 o rvr0k;.eorzaf wtw-6d from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350.0 mL ojv l0z z3gv df23)uag+f 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 m9; x x6kdxjg+oL 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 gej rm,4o. y6uplaced 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 a long, n;v;im:of8*)twfft. dtl * s bjarrow vessel so it can expand in essentially one direction only, show that the effective coefficient of linear expansion is approximately equal to th ol ms )tfj:ftw8*tv.i*;bd ;fe coefficient of volume expansion $\beta$.

(a) Show that the cha )::crs3ux(wq qqbq2onge 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 length l and width w has 8h3cp-mkz xk jw;6e)xcoefficient of linear expansio)xkw kp-e hmx j8;z63cn $\alpha$ 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 isotro cm; x7:*tsekcpic 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 keeps perfect time at 1ht skj ,).+n4svq yd*d7)qdsts4, +hk .y jnvd* $^{\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 ns)1j tqw(a) tt/rut9bulb has a volume of 0.255 wtrtj au t(s/))9 nt1q$cm^3$ 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 wheu+ y50 scg*p*npjsv;h1 hi jp3el of radius 0.41 m is rotating about its axle on frictionless bearings with angular velocit;5yipg1spsu j3nh0p**vcj+h y $\omega$ = 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 descwd8 qtp4fc8yt d9ohc ,e.g3cso79 j (ired length when at 15°C. How much stress is required t7pfdsc w htq.j,c gtc3do8 49oyc8 e9(o keep it at this length if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of crossyxioa+13. bak/b vl 0z-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 ca y(r8gshtz *)p3dx-,k/wue d m 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 scale)/zbz-t:qz ib9o y f(r:
(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 temjn/: hvkhlqx. l3 d9m)perature on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun are aboujt(993dm vmamt 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 luw.k+)e id(gpressure and a temperature of aboutwg .ui+( ked)l 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 usin8/bod orb-x+:wfp;l+opl* gz g v9b3eg the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg ofm 0hxps;pnq8h ;svr5 . 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 u9i;tw3rg 3cu 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 heli71 3j8psiid -u:e8r 2mony vpdum 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 ho+ihn)w-r t+rq lding 105.0 kg of argon gas at 3 h+)ir rqn+w-t85 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kgys:6cauc r5 hjc ,0mc7 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 buos9cxlj,7ftn5m+2z8 vtxs* n m yant lift by heating the air inside the balloon, which makes it less dense th xm*c7tm 8ns,j ts9fx v2n+zl5an 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 aire, .un.ovc lg3q8n80q1sjpoo 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 a kf+l+br6ml)doyaq s) i;+qf9t 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 childqw- 6epqt6;ungps -z0 :dh(* aa0s bqd’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 number of molecules6 ;lggk(nw;hn / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How many molecules? 5s dr543hi fux   mol    $ \times10^{25 }$ molecules

  Estimate the number of wb6yyu5; 8ls7etl r1cv3+m jl(a) 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 volum ujk,lkhvf gwu0(d1/j.5/ dohe 5.1$ \times10^{ -2}m^3$ is filled with air at atmospheric pressure at 20 $^{\circ} $ C. The box is closed and heated to 180 $^{\circ} $ C. What is the net force on each side of the box?    N

  Estimate how many mo /vw0c; ro9vwi+.p 3 05c wpczkg t9nu4yax:cclecules of air are in each 2.0-L breath you inhale that were also in the last br;9. t n5zx0wri4c3 wccwcuk+y/v oa: p0cvp 9geath Galileo took. [Hint: Assume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of an oxygen molecule at zifb7+ 24kv zt.pyf 4j ,jmi.bSTP? +zifjp,j 4fv72.i.zkb4y m bt   $ \times10^{-21 }$ J
(b) What is the total translational kinetic energy of 2.0 mol of $O_2$ molecules at 20 $^{\circ} $ C?   $ \times10^{3 }$ J

  Calculate the rms speed of helium atoms near the s.wm0hhrvf4, ddpjf* k5jf+9nurface of the Sun at a temperature of about 6000 Km 54vf+j hd nw*fj k9.fhd,p0r.    m/s

  By what factor will the rms speed of gas moleculo ,kcs k,8:reiyhcd38e6g+ fces increase if the temperature is increased from 0 ie8 +sc:g yfk3drhcc,,6 8 eok$^{\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, giyq46,)fni.iad 2ct( lh mi;: ggckg/aven in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, fg);(iya h6ga,nm i:ql. dck 2t4gc/ i7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas yuq8 iijo mzz76p3y*(5szos3 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 a*) btadfad05g gas is doubled while its volume is held constant, by what faa t5)*a bddg0fctor does $v_{rms}$ change?   

Show that the rms speed of molecules in a ga qb*u7v l v:jv2m-5pnys is given by $v_{rms}$ = $\sqrt{3P\\rho}$ where P is the pressure in the gas, and $\rho$ is the gas density.

Show that for a mixture of two gases at theyjep).h n8hvn7d /)el- sz (fg same temperature, the ratio of their rms speeds is equal zv)ye8 7fjesp)-h.nh( / g ldnto the inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrdvah3 +2mp.pv ogen 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 speed of an oxyg 8le9p eekhazmx477u(en molecule at 0 $^{\circ} $ C    m/s
(b) determine how many times per second it would move back and forth across a 7.0-m-long room on the average, assuming it made very few collisions with other molecules.    round trips per sec

  What is the average distance between nitrogen mo:lriod05 zbp3g(3yfgb2 u;d ylecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular mah3y 4un8rl8i1rmy bh1ss is 89 u in a living cell hr3nm 4h11 li88 ryybuat 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 i1) xvnxqamq.3akl)2t9i l;t be written P = $\frac(1)(3)\rho v^2$ where $\rho$ is the density of the gas and v is the rms speed of the molecules.

  The two isotopes of uraniuvf i 0haawupt4f u3(0:m, $^{235}$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, 79z0rnopq0 3-hp8w q)(dk6mqtnfbt 5oiv6n s in what phases can $CO_2$ exist? (b) For what range of pressures and temperatures can $CO_2$ be a liquid? Refer to Fig. 13–21.

Water is in which phase when the pressure is 0.01 atm and the a.sw5r:p;dy tunw 1y)temperature is (a) 9)y;y.wrs : ndptwau 150 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if thejy zq4g *k,7 shja+)t-ky w,e ;1dpjhj humidity is 50% on a day when the temperature is w 4+gsyk- z jhy7)jktq,*;da1 ,hjejp 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place wherf yx94go:a ): ezbvgo:e water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular wscd vg .0o-o,v p*:mgplace in the mountains is 0.72 atm, estimate the temperature at which water boils.c .dw:,-o0*ogs mvvpg $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure ofj8c/7/3jgsk.jnd x mqc/s*3owl 1bju water is 530 Pa and the relative humidity 7jl/ 8/3sdx*ncw3 j/ucgj.qs o 1m bjkis 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on 0w-lzl0qhrp o258jjd a day when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressurytcldi9sge8k.bn2o t7l-(u6 e cooker if the water is boiling at a temperature of 120u9 ibdl6-se(gk7y8 n totc2.l $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room of manp0sr(b (g-e gmik.t 8ae28ji 3/9awuiqu9volume 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 -;txve-gs8 ibof 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 Table 13–*t1i o 2urb 6gblsq (c:py:u3k4) to diffuse a distt kuisg(:* 2qurbboyp36c1l: ance 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 surfau/ e7rt-ph:ktce of insects to the interior through tiny tubes called tracheae. An average trachea is aboutke7 r u-phtt:/ 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 meqzp bw98m-1 7o*ws azzp x-y,gsx xj9.asure has been calibrated at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A precise steel tape measu27glvr w-g 6lvre 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:ck( ,b0g2psmghh mw0 calibrated at normal room temperature. How much error will be made in a recipe calling for 300 mL of cool water, if the waterw,s00(hc km2phbg mg: 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 he5*q8mf/w m l abns*l9wlium gas cylinder is initially 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fractio*l9wl* / mm bqw8sanf5n of the original gas remains in the cylinder?   

  Estimate the number of air molecules in a room of length 6.5 m, width 3.fes y0nl2,xe9: :kc(pu) pa ll1 m, and height 2.5 m. Assume the temperature(0:xp,n a ckul:2 l plf)y9see is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of mattz8 ezpd6rn6ao n. or6 :dt.c8ler 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 attaiu)5buv0o0iggx -jiou1b lh0 e;qk; k:nable using the best available vacuum techniques is abo uk1; q0og;o bj0ehb)5u il-x0k:uigvut $10^{-12} N/m^2$ 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(+as)h3qnhlp2be 3 qk.5 L when 10 m below the surface, to what volum (klh aq3nb2)p+qh s3ee would his lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmosphere at a se fe mg5 z0dot;: **.xthpord:peed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this speed correspond to f*oget h:.; 5r*d0opdemt xz: 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 increasol5y g d2wf+l7ed 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 75/cl;o0l)phz s,* p(o es c/4-cyr*vv chumvy 70m$^2$ (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 xz n*g /hb0*5cg4f ,tp tu;tk1icge3u surface of the Earth, estimate the total numu;be c txhp4kz ,g 013f5*ntu*tgg i/cber of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of w; 1y5xx7s1 c (n;re5p jtsabwnitrogen 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 hospital has gauge pressure xl kqwvh7 -t2.= 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmosphelxk-wv 2h7. tqric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats i py8*as*dv w.fn a bowl of liquid mercury at 0$^{\circ} $C. (a) If the temperature is raised to 25$^{\circ} $C, will the cube float higher or lower in the mercury? ----待选择----lowerheigher 
(b) By what percent will the fraction of volume submerged change?    %

  The density of gasoline at 00l */gjmcysese qa60;$^{\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 equator at:;hq3f43r c 2na6loh+ ohclxb 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 idxs t-zk29/p7 txu5bonto 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 standf/:,l1 y1iax6xlyqnward, 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 rmig8 :h,iop lj s8p;1of 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 t1 d0isob)d 7jphe 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 against3q+wwh9gsmq 0o):kqy gravity by tennis balls thrown vertically upward at it. How many tennis balls per second mukog: yq0q+qs wm hw39)st 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 releaswn 3 w7so 26tn5rf/csues a 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 behaves as a pws /f2s o67twcrn nu35erfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure in the8melr9 o * s(i3p)idlep2l;th air on the following two days: ) 8l9 si peiht*(r2;lod3pmle
(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 oawmf 9w5*.hcg2 7t)rm kvn+4/fnlvx lf iron at STP, and when it is a solid deep in the Ea52 fmk+/nh *rg4n .7v mvlt ac)f9lwwxrth 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, tn. r90r 0x ;ignixmk:-sbb4hhhe coeff.xkms4; -riin b 90 bhxgn0:rhicient of 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.