Which has more atoms: 1 kg of iron cj;k9rcn,8rb0uv)j -whyhc 6or 1 kg of aluminum? See the periodic table or Appjccn,w608u; b )j9r chr-vhykendix B.

Name several properties of materials that could be explh0ges23.sv jngq 19qu oited to make a thermometer.hv ge 3.g9j01q nq2uss

Which is larger, 1 Cfb s(( bmvepvjx+k 0;cu r4e6) $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B3 w:rn h7ec:cj is not in thermal equilibrium with system C, what can you say about the tempcw3rjhc:n: e7 eratures of A, B, and C?

A flat bimetallic strip consists of b:a*)m f)uv ecd 3qeo1aluminum riveted to a strip of iron. When heated, the strip will beo1af cequ*eb v)m3d :)nd. Which metal will be on the outside of the curve? [Hint: See Table 13–1.] Why?

In the relation $\Delta$L = $\alpha$ $L_0$ $\Delta$T, should $L_0$ be the initial length, the final length, or does it matter? Explain.

The units for the coefficie;mrka;/n gw 2znt 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 control a furnace (gsgf dw grmqfr e;fn(26 t,)/: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 liq/6rtf:dwng,fgrqe ;2 f (mgs)uid mercury that conducts electricity when it can flow to touch both contact wires. Explain how this device controls the furnace and how it can be set at different temperatures.

Long steam pipes that are fixe /csliycq9 q 5y 1,.my 15jcm1txwu0eyd at the ends often have a section in the shape of a U. Whyic91jtw05y/q, x 5u .mcy1sl ceq1y my?

A flat, uniform cylinder of lead floats in merc ev 9mn;qx:ps3y7yr3 iury 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 fir4juue) 9ib fwti3, 8jkst placed in a hot tub of water, the mercury init9k 3)4i,tiuwu8j bejfially descends a bit and then rises. Explain.

A glass container may break il r/ it1ugd tnuv(:1u2f one part of it is heated or cooled more rapidly than adjacent patrigutv u:/dl1 u(n 21rts. Explain.

The principal virtue of Pyrex glass is that its coeffic6z 4j0usa,j liient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives0 jz, 6juasi4l rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurate a msq,ku h*wq 32o6n4ydvf8jc :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*m:)ca q 3mt* wagedg8 bulge so badly the can will not stand up. What has happenegm q:c)*t ea* d3agm8wd?

When a gas is rapidly compcj ps+:e7 buheje 51dq+pl2 5rressed (say, by pushing down a piston), its temperature increases. When a gas expands against a piston, it cools. Explain these chae:he++b 57 jejc qdprs25lpu1nges 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 water incrru,n.g(g)eqhz*k.1l pa yv k-ease or decrease if the temperature is increasqy(g epv u,*a.kz nl-h.k)1gr ed from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from ki5uwqzi* zhel;jdb) ;4 netic theory and the relation betl5iq*w 4;zjbe ;hd u)zween average kinetic energy and the absolute temperature.

Explain in words how Gay-Lussac’s law follows from k.lni 4)ibf*2nqubq- dinetic theory.

As you go higher in the Earth’s atmosphere, the ratio of8vc a.axc-bkh4upy53 $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth h//t ibh w*+3)jl3bcjpk lf: crefers to the minimum speed an object must have to leave the Earh+: cpjl bbi/33l/fcjk )*thwth 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 the Moon has practically no atmosphere.

Alcohol evaporates more quickly thany q+/ex v(f-b8a;pgbn water at room temperature. What can you infer p-b +ef/n b8a(xqv y;gabout the molecular properties of one relative to the other?

Explain why a hot humid day is far more uncomfortable than a h8om,ssy8 k5zt f*+p tgot dry day at the same tem 8sto gk*tf85z +mpy,sperature.

Is it possible to boil wat;udd(bn:ryc 3 er at room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the aw:0 )g;zqdspjx3a k8+gy (np hir temperature is the same but the humidity is different. Which is more dense, the dry air or the humid air at thek sy;dp8zw3 (n:g 0p+ahj)gqx same T? Explain.

Explain why it is dangerous to open the radiator cap of an q+ x7b .kiw-iprm :(yloverheated automobile enginer - : ibyqk+mxpl7.(iw.

Why does exhaled air appear as j 20exorv5vy8 a little white cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram copper egu g/r(a rd30penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring a9 we1+9jeoizcompare to the number in a silver ring of 1aj+ez9eo 9withe same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is oftecl7 euqs3trp )i*y; .f2i ru3qn taken to be 68°F. What is this on the Celsius scale? 23ifrl3u)yts7 pqicq;u .er*   $^{\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 tem4v) uhqjt *,ccperatures recorded are 136 $^{\circ} $F in the Libyan desert and -129 $^{\circ} $F in Antarctica. What are these temperatures on the Celsius scale?high =    $^{\circ} $ C
low =    $^{\circ} $ C

  (a) 15 $^{\circ} $ below zero on the Celsius scale is what Fahrenheit temperature?    $^{\circ} $ F
(b) 15 $^{\circ} $ below zero on the Fahrenheit scale is what Celsius temperature?   $^{\circ} $ C

  In an alcohol-in-glass thermometer, the alcohol column has length 11.82 cm -g1ik5un*tga at 0.n -51gik*augt0 $^{\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 bs zv rypp413i(wb 4we)uilt 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. 1 g wxhgr9ut8hy2* 39*jrk8biob i 4kzr2r2nt13–29) is built of wrought iron approximately 300 m tall. Estimate how much its height changes between July (average temperature of 25°C) and January (average temperatub3k49g 22hijirt8xo9t2 uy gnhr* *8z1 wrbrkre 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, ri.oq u+i( 9mjny7er+fx vets that are larger than the rivet hole are often used and the rivet is cooled (usually in dry ice) before it is placed in the hole. A steel rivet 1.871 cm in diameter f. iuj+ qrmnoyxe( +97is 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 4q:oews 2v16n9ac 7ur- ez-gxq $^{\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 6 /ztqtox l,k1its change in volume if it is /1lxqo ,k6zttheated from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350.0 5l,zvc di 1k9exf8 m4dggisncf1;s :-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 5th(c4lrt3ff)tcqf w* ex mv4spe(o4+ twl(,,5.50 mL of water at 20 $^{\circ} $ C completely fills a container to the brim. When the container and the water are heated to 60 $^{\circ} $ C, 0.35 g of water is lost. (a) What is the coefficient of volume expansion of the container?    $ \times10^{-5 }$ /$C^0$(b) What is the most likely material of the container? The density of water at 60°C is 0.98324g/ml.

  (a) A brass plug is to 5kksu .,t vfp;be placed 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, narrow vessel so it lx g 1e(kmook8 / q4qn,apl+)jyjj3 c9can expand in essentially og3lk +oeomn)ykp(jjq1x/j la c, 9q48ne direction only, show that the effective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the chanth (cegrd9 hob/6c 84lud3tr: ge 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 8x/eekk+cwi( g.xfl4xh.rq*j) r0 ouwidth w has coefficient of linear ex8+xe xw.(0/) fh*rlkkgcuqri4x o e .jpansion $\alpha$ 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 isotropic solid, x * .wgv ha,lnf4vemx0w0vg.2$\beta$ = 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 bybck5y mz5wh0:):0 u,t*wh0ojixt or rass and keeps perfect time at 17 m:tyto 0:owj 5u zcbryk 0hh5,*) ix0w$^{\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 rm5k6o 7coxm9 thermometer has an inside diameter of 0.140 mm. The bulb mkc6957roo mxhas a volume of 0.255 $cm^3$ How far will the thread of mercury move when the temperature changes from 11.5 $^{\circ} $ C to 33.0 $^{\circ} $ C? Take into account expansion of the Pyrex glass.    cm(b) Determine a formula for the length of the mercury column in terms of relevant variables. Ignore tube volume compared to bulb volume.

  A 23.4-kg solid aluminum cylxoa5i,w((kws a6 oa cre 2-cu.indrical wheel of radius 0.41 m is rotating about its axle on frictionless bearings ( 5(ai.awau62x,sr coek-cowwith 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 desire j3k7mc11 pocnd length when at 15°C. How much stress is required to keep it at this length if the temperatck3 c17jpno m1ure increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of capu3nb0h: f sx+,x nh(ross-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 134.12pcm+ x 4y*gm2o2 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 temperatureixmn -4po1 y1xj ; q5-1zc)t 0dpmsbbcs on the Kelvin scale:
(a) 86$^{\circ} $ C,    K
(b) 78$^{\circ} $F,    K
(c) -100$^{\circ} $C    K
(d) 5500°C,    K
(e) -459$^{\circ} $F    K

  Absolute zero is what temperature on the Fahrenheit scale? ns/xi xj(yzjyxc:t+).r f+ )d   $^{\circ} $ F

  Typical temperatures in the inteb)xbvjq y1a7 q+ p-;q4xl1ce-, ewlxlrior 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 tem zmx .;7d ff j5wji*a;rgm4/luperature of about 25fz jdx;au*mmlf;j/wr7g4. i0$^{\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 u2av+ae.; pd1qyfo -sfsing the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of nig kgb)v)5s5nhh -m3outrogen ($N_2$) 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 STPd3ytoi ;-ql 63 rssol4 contains 18.5 kg of nitrogen ($N_2$)
(a) What is the volume of the tank? $\approx$   $m^3$(“Round to one decimal places)
(b) What is the pressure if an additional 15.0 kg of nitrogen is added without changing the temperature?    $ \times10^{5 }$Pa    atm

  If 18.75 mol of helium gas is at9.r6)c7of6gwg xsi1i/v r; a xxoiul8 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 argoos+igq 7 d7e9/wl k fv.3pq/unn gas at 385 K.+upv3qw7iq9fsl /dgonek /7 ?   $ \times10^{ 8}$Pa

  A tank contains 26.0 k0/vxt)1 bl3dg ixxw6 vg 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 air insidebln/jr(i b )+-g-8t uheg /jgp the balloon, which makes it less dense gge(hb/p)iu+jj8gn l -t r/ -bthan 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+w+w g9kvgl(cl ah :h-j);wfs 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 18m z4xn5n4 zg9p.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 sea level and 20.0 qscdpdsi/- 678djcj3 $^{\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 o53:6vbfkvcf m f molecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in9kpi)7)b q7h 3yy cklk 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a)zvq ** z96m t:pmidmo311qmlu moles,    $ \times10^{22 }$ moles and (b) molecules of water in all the Earth’s oceans. Assume water covers 75% of the Earth to an average depth of 3 km. $\approx$    $ \times10^{46 }$ molecules

  A cubic box of volume 5.1bmiw,s3 . s-cul.1k3ofcqz l *$ \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-Ln7yxu: ,rx6 yv breath you inhale that were also in the last breath Galileo took. [Hint: Assume the atmosphere is about 1,v xrun67 y:yx0 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy2(x.1r tqaq 6 t9s*z1dzjnkt n of an oxygen molecule at STP? zns* 1qtr9j a n6 (qd1k.2ttzx   $ \times10^{-21 }$ J
(b) What is the total translational kinetic energy of 2.0 mol of $O_2$ molecules at 20 $^{\circ} $ C?   $ \times10^{3 }$ J

  Calculate the rms speed of helium atoms near the surface of the Sun at a te39eqp v)t 1v/msk qg-tmperature of about 6000 K.gtv q3mt9k eq1vp)s/-    m/s

  By what factor will the rm wyw*h; d6m;ocxki)lu,1zpx, s speed of gas molecules increase if the temperature is inc6)loh cz mw ip*uxdx; ,ywk1;,reased from 0 $^{\circ} $ C to 100 $^{\circ} $ C?   

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

  Twelve molecules have the following speeds, given in un +(se3ant l)6hk o (lo,u7cjztits of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calculate th)e6 l o3(n(htts7u, o clzkj+ae rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules infz)c.;h) vqh+lp udy( 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 a gas is doubled while its volume is held cont:yc9 :c aa o6tmksn4*stant, by what factor do*:y6 kaso9 c4na:tcmtes $v_{rms}$ change?   

Show that the rms speed of moleculesw+3ton4kjy-js2dr5a / xwnp * in a gas is given by $v_{rms}$ = $\sqrt{3P\\rho}$ where P is the pressure in the gas, and $\rho$ is the gas density.

Show that for a mixture of two gases at the same temperature, the ratio of ,d opb5v8 9 oq5nv: zb3vxazr8 cuvyewb-,6+ ktheir rms speeds is equal to the inverse ratio of thoc55w63:u9y zv qp,vba- 8z b8ov k dxr+v,bene square roots of their molecular masses.

  What is the rms speed of nitrogen molecuf +:)6 o7-o ouwuatwrnles 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 h oq8)xbnc*.tjp2( -2w7g 6cl pboqiian 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 nitroge ;m nzsszvzpd)g: t *6r41cjp(n molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of aigdgo /d 7u,08o vmn;zn amino acid whose molecular mass is 89 u in a living cellng z;8ovd7m0 /udig,o at 37 $^{\circ} $ C.    m/s
(b) What would be the rms speed of a protein of molecular mass 50,000 u at 37 $^{\circ} $ C?    m/s

Show that the pressure P of a gbqukn;f0 lwd0+ 0mt i5as can 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 urbfrsb s6)3lndfh/x. 2anium, $^{235}$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 pre ct89jpnn:9t,gdhb k c 0(gkt5ssure, 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 5 ip q4mv.hqu hn*)0uhthe pressure is 0.01 atm and the temperature is (a) 90i.4p*uqm qhhn 5vh0u) $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) ifv3v5r +7e 3bul lnzl91xpl zb) the humidity is 50% on a day when the temperat3v5lbu zpxn+)b9 7 3l1e lrzlvure is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure aqndad4;2f+ ipuec46j 8 rux+o t a place where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mo6 m8v0 i+jufud .dk-v;uud 6aeuntains is 0.72 atm, estimate the temperat ;ed ui +j6 .6uufdmv-8d0akuvure at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of water is3o n,8cz4b e y/8jixj/dfu2yf 530 Pa and tj8 4n byo xjd fe3//fizy2uc8,he relative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of wa mcl2:5 ;h0yzxge:hpiter on a day when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cooker if the water is .is jd :;abb,,4) kvl 4lol24vivzwku boiling at a teml4a2idvjl k; 4ibws,lov4)u: . vkbz, perature of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a rool8 uyu 0/o8kbj07z3aktaa10bumco7:)i jdfem 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 5 n ;sekrbt0b21 void .t,4nor-$^{\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 13–4) to diffdwnfkh6wl6 0 :use a difdw nw6kh60l:stance of 15 $\mu m$ in water at 20$^{\circ} $ C if its concentration varies over that distance from 1 mol/$m^3$ to 0.4 mol/$m^3$ Compare this “speed” to its rms (thermal) speed. The molecular mass of glycine is about 75 u. t $\approx$    s ([color=rgba(0, 0, 0, 0.85)]Round to one decimal places) $v_{diffuse}$    $ \times10^{ -5}$ m/s
$v_{rms}$    m/s

  Oxygen diffuses from the surface of insecj,yiacsj rk;3i o:*9 uts to the interior through tiny tubes called tracheae. An average trachea is about 2 mm long and has cross-sj ,3r*9;u:yjkioa ci 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 f:vy )gpj3 ;w x(g9ezl20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A precise steel tape measure has beeqnpak+0kij+ )+3c7jxbj6v7ok -l s6 tt dzo7vn 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 whei o vq5e(eef ko5.83as calibrated at normal room temperature. How much error will be made in a recipe calling for 300 mL of cool water, if the water and the cup are hot, aee .eo8q 5h evf5(oi3kt 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure iwr5x fc:b tq) 1yi.jo0fsg+6qn a helium gas cylinder is initially 28 atm. After many balloons have been f)s+cbfrq5 w1o:qyxigt 60j . blown up, the gauge pressure has decreased to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number ofeul kfg8+v/ vv8k11bs air molecules in a room of length 6.5 m, width 3.1 m, and height 2.5 m. Assume the temperaturge 11v8s fvv+8ubk/k le is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is about cj6*duyyy bp360 0rcb 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 attainstey p, gz,xuo 42vcq o 8+qh8;/krz/bable using the best available vacuum techniques is aboq,kxhsg2o/e +bv8,uyc 8 pq4rz/;z otut $10^{-12} N/m^2$ 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 bels2lr+pt2 j5 * 4tyork(iii+zqu8s 7 ugow the surface, to what volume woul27 rziisgrtjytq8+ls*4 o u(52u kp +id his lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moonx/5e e/m5pyrl 9rh+ uz enters Earth’s atmosphere at a speed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this speed xr/pm59 r uz5yl e+/ehcorrespond 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 incre*rvlberisfg-kyr0q3( . fd 8 /ased 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 volumea2y38 +4xl u cj5rtuyve)k/po 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 a /hv zims8e;8shcv:vwx q .0. ;u/vzewx7os0 ttmospheric pressure at the surface of the Earth, estimate w :8e/zs0v/ov vw xucszt s. q8ehim0 ;h.vx;7the total number of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed * x,2p(o pkjgdof 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 d+e-86b p4csjalt1w 1m2r hjr :3pdwn used in a hospital has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flowmn+w 3 j1wdhastb1-cld2er:6 pp j4r8 rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liquid edf8 lvwl; -n1mercury 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 gasoliw.l4h9nksiuv i62;b byat*9go) 5 lcv ne 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 equator at 25u. obe) n;ula5$^{\circ} $C, but then was heated to 45$^{\circ} $C, how high above the Earth would the band be (assume equal everywhere)?    m

  A brass lid screws tightly onto a gh9tj 5*mank1 yiej+h4lass jar at 20$^{\circ} $C. To help open the jar, it can be placed into a bath of hot water. After this treatment, the temperatures of the lid and the jar are both 60$^{\circ} $C. The inside diameter of the lid is 8.0 cm at 20$^{\circ} $C. Find the size of the gap (difference in radius) that develops by this procedure.    cm

  The first length standard, adopted in to zaj8;i2,l tuwck8, dhe 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 co ,;.y7oowfq qharged, has 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 Earth 1839qn)q wxq.zigtm lis $ 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 smg ikc(8 u1nc1uspended against gravity by tennis balls thrown vertically upward at it. How many tennis balls per second must rebound from the lid elastically, assuming they have a mass of 0.0c(g 1cm8uin k160 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00wx6+ 8pa-i q -xyemh6h-cm-diameter (spherical) bubble of air from a depth of 14.0 m in a lake. Assuma mhe8x+pxi yhw--6q 6e the temperature 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 press;m;d0yg7zzgzk ypk1+ure in the air on the following two days: kzp;d gm1+zk0y ;z g7y
(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 thevdx-4 8jm2tj /6d elfg9 8xexm density of iron at STP, and when it is a sov/x-djml2j 84dg69 e8f mx xtelid deep 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 ideal gas at constant ppxdd(t61/ 7+ lw flcfqdks4t:0y yfm:ressure, the coefficient of volume expakt:y46f (+dm1 dt0fsfxpl7dq:w cl/y nsion is equal to $\beta$ = 1/T where T is the temperature in kelvins. Compare to Table 13–1 for gases at T = 293K (b) Show that the bulk modulus (Section 9–5) for an ideal gas held at constant temperature is B = P where P is the pressure.

  In humid climates, people constantly dehme f3c8 u4ty(jumidify their cellars to prevent rot and mildew. If te4jmf3 cty (u8he cellar in a house (kept at 20$^{\circ} $C) has 95 $m^2$ of floor space and a ceiling height of 2.8 m, what is the mass of water that must be removed from it to drop the humidity from 95% to a more reasonable 30%?    kg