Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodic d+ t,cq6lq*v 9h3v1.emtzba o table oo*,31 69vq.hv mtael dcbt+zq r Appendix B.

Name several properties op )hb5plcfp4q0k jw51f materials that could be exploited to make a thermomet 0p4bjhfpk51qlw)pc5 er.

Which is larger, 1 Cil)a0ae ja ) ksr4kq// $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium n:tm):zzo8 5r/gqnak m,g /qm with system B, but B is not in thermal equilibrium with s tnq/agmmo,/q::z)rk gzm n58ystem C, what can you say about the temperatures of A, B, and C?

A flat bimetallic strip;bhdxbah 2ut,*s0tv y+ 6+ivp consists 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 u dvb svyt+ a,h;*t+b260x hpi13–1.] 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 coefficientg7-5j3 ;)i b c31gm xyzobttcq 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 cono/lhirxdyfk **qqg.e b-2q,w*5j w r +trol a furnace (or other heating or cooling system). The bimetallic strip consists of two strips ow*h. -drrqo*/q je,xg5by2liw+q*k ff different metals bonded together. The electric switch is a glass vessel containing liquid mercury that conducts electricity when it can flow to touch both contact wires. Explain how this device controls the furnace and how it can be set at different temperatures.

Long steam pipes that are fixed at the ends often have rps8 qe89e8ghrl6)pt a section in the shape of a Us8)6 eprgph8ter8l q 9. Why?

A flat, uniform cylinder of lead floats in mercje k)z joop ssw:l 9dw60j19:gury 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 tu5sydyi xl/q51 *l 8wdn+sz) nub of water, the mercury initially descendsnxd5z ll) d5s*w1y s/ uyiqn8+ a bit and then rises. Explain.

A glass container may break if o a0xjckcfxv7kap/p4w2q7mm-v,+eqq2dq9 9 b ne part of it is heated or cooled more rapidly than adjacent parts. Ex0 e qd92xajckpp4maqfq m 72k-c+b/vq ,9x w7vplain.

The principal virtue of Pyrex glass is that its coefficients0o7vto.vk/dvuol1o,4 f iq+ of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to u q1.+vokf/ool 70tv, dsoiv4the increased heat resistance of Pyrex.

Will a grandfather clock, accur ;4wa zhyx+4rzate 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 soda will ca opdohay )*37cpjp-3dv,1 ghxuse its bottom and top to bulge so badly the can will not stand up. What has jov x-dh ohg)d3p13cp,7 a*pyhappened?

When a gas is rapidly *g+ k)/fmda(,k jctnlcompressed (say, by pushing down a piston), its temperature increaseadk)(+jkfg,c mtnl/ *s. 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 moving piston.

Will the buoyant force on an aluminum spltok/qa*cncrs/ifp8sy - 9.( here submerged in water increase or decrease if the tempayic sn csp/* (k .of-8tl/r9qerature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’lg;ch d3h; dl(ro 2q4os law follows from kinetic theory and the relation between average kinetic energy and t hcoldl4h ;d 2g3(rq;ohe absolute temperature.

Explain in words how 5xz x y td p:edv,6)rj qd+93,.flcqtaGay-Lussac’s law follows from kinetic theory.

As you go higher in the Earth’s atmosphere, tp -*uvwee(7rs74zw hjhe ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum +,t7m audy-xmx .g1lyspeed an object must have to leave the Earth and never return. The escape velocity for the Moon ,mmtax-y.ld 1uy7+ gx 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 than water at room tempe 6uhfeiy9az vhi-tlge 7 ,g,1)rature. What can you infer about the molecular properties of one relative to7f t,zel6v y1gh ieg,i)9ahu- the other?

Explain why a hot humid day is far more uncomfortable than a hot dry4y-4o3)pdp n1w7xxgk8jcnyx day at the same temperat 17o-ydncgj)wk4pxpn x84y 3xure.

Is it possible to boil water at room temperature 6 )ffjd0 k0aw+;xzdd 2 no9vow(20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the humidity i6xe*q1 z6 jn)qn nabs,s different. Which is more dense, the dry air or the q66e nzasbx ),1n q*njhumid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap of an overheated autbpjdgow4 f+ce 6/s 0e-hd*xg; omobile engine. o -*/c4 heddjep;g6wf0bx+sg

Why does exhaled air appear as a little white cloud in ( )2.t3d2l.g:cd v4tzy1nt j rrir daathe winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram copper penny?p;q9kzeg-1uwzpk : , a   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ringru79u5.my ,lgpeg s0i compare to the number in a7gpuieymu .gs90 l,r5 silver ring of the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is);wnejv8 dh0 k/aru 8n often taken to be 68°F. What is this on the Celsius scale?hv8aew;n / 8d runjk0)   $^{\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 au4ab(tgd+9wn.r1s:xb 9rk mw:m2s jzh;iq. o re 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 w;mamge8d8k3a1 yk;9z -r zw athermometer, the alcohol column has length 11.82 cm at 0.0 kde13 mk zzgw9;8rmay;a8aw- $^{\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 slabs 12 m loygd+ys,o h dyo 5*z7 ,kury)d,ng (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 300 mjo( e mp b,(iuavv-2+a tall. Estimate how much its height changes between July (average temperature of 25°C) and January (averag(iuaea-v o2b+m(pj v, e 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 often usc dvxcetxb ya8 /tp;dcr50u4 ff5* o00ed and the rivet is cooled (usually in dry ice) before it is placed in the hole. A steel rivet 1.871 cm in diameter is to be placed in a hole0t;5y/t05*af8dbr vpx0 e4ocd cufxc 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 ato;u w s6fv4j6(zflww7 4 $^{\circ} $ C is $ 1\times10^{3 }kg/m^3$ What is water’s density at 94 $^{\circ} $ C?    kg/$m^3$

  A quartz sphere is 8.75 cm in diameter. What will be hhhkshuvm2m2y+s 8ewc u my81( ))k9nits change in volume if it cmh(h+ )29hyksu) 8 me8yku21 hnwv msis heated from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350.0 mL of npr g/3 zx zsc,-:vl*awater 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 55.5xncn-)tf 8efpzk boj4pz )7qry9 2,4y0 mL of water at 20 $^{\circ} $ C completely fills a container to the brim. When the container and the water are heated to 60 $^{\circ} $ C, 0.35 g of water is lost. (a) What is the coefficient of volume expansion of the container?    $ \times10^{-5 }$ /$C^0$(b) What is the most likely material of the container? The density of water at 60°C is 0.98324g/ml.

  (a) A brass plug is to be placed in a ring mays xs-13 5lv1 pxnuka /tn-n0 hx)u:ytde of iron. At 20 $^{\circ} $ C, the diameter of the plug is 8.753 cm and that of the inside of the ring is 8.743 cm. They must both be brought to what common temperature in order to fit?    $^{\circ} $ C
(b) What if the plug were iron and the ring brass?    $^{\circ} $ C

If a fluid is contained in a long, narrow vessel so it can expand in essentnnvjz;cp 82c1ially one direction only, show that the effective coefficient of linear expansion is approximately equal to the coefficient of volume expans vn8pj nz21cc;ion $\beta$.

(a) Show that the change in t-wwl5e47l2 ca0dxit.g wd4h ohe 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 coefficient of linear ex(rt;:po0u ktgsc3v- e: 0rcot ku;spevt3 -(gpansion $\alpha$ 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 isotrrq+j-f+i0q ba opic 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 grandfat23.2su8tmcvl3 q vlvk her clock is made of brass and keeps perfect time at 173tv8uqvmk2 .v32 slcl $^{\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 insidr *:i3p5 9the1y-frjgw o n5uqe diameter of 0.140 mm. The bu59-h :*rq5y3po 1 fng wjuetirlb has 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 cylindrical wheel of rayfzbim nq3j 21m30l *vu2kh5m*xwz y,dius 0.41 m is rotating about its axle on frictionless be2nuz1 2m zfk lmwx3vh*ibyj,q5 03ym* arings 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 length when at 15l)yctdpy -0l, 9-(o hmppgph (°C. How much stress is required to keep it at this length if the temperature increc h )pl(m0yop-ld- ,ph(9ygp tases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-bea9ks n0 n4e(mea 3i1tenm 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 1ff5fw s5bqq6 x(pi6 v1ie;8td34.122 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 te( 93p(rdz2m0bmzs jhq mperatures 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 scaz lkzepaf3:120t(0 tvh rvz5 gle?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth a1+bot g)eu7 vtnd 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 pressueexzmp1 k0 0ru6n((uxre and a temperature o((xz0r u6k mupexe 0n1f about 20$^{\circ} $C is compressed in the cylinder by a piston to $\frac{1}{9}$ of its original volume (compression ratio = 9.0). Estimate the temperature of the compressed air, assuming the pressure reaches 40 atm.    $^{\circ} $ C

  Calculate the density of oxygen at STP using tj-v/ l6wiki:-mq 4doo he ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of n3+ -*zbzm:65x 6h hav flnaounitrogen ($N_2$) at an absolute pressure of 3.65 atm. What will the pressure be if the nitrogen is replaced by an equal mass of $CO_2$    atm

  A storage tank at STP contains 18.5 kg of nitr*s7slz30 x vwrogen ($N_2$)
(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 at 1/ w1lu3jb(kud 0.0$^{\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 containerd0jl,v e+6ox r holding 105.0 kg of argon gas at 38, rljv6o edx0+5 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg of a4gk*.y,q:pq9kok lx $O_2$ 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 ina;:i *.eyvm 7a.2o tffjxxc;mside the balloon, which makes it less dense than the air outside. Suppose the volume of a bal2 yexf:.7avo *atmx .j;ifmc;loon 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 withf yyyk+dryk019n2( tk air 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 18.9 bq( bnj,czt)kop4 b*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 hah e99dyt+e/gm1bf 3h und 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 om ys9oqzkrbgw)+hg36jk0 -.xf molecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are thefe hgl3u34 n g:5fsp,tre in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) mole5sl ea+hx+-. e(1qfp.wwgpp6z/j uj gs,    $ \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.mzix(g 0pm8q 01$ \times10^{ -2}m^3$ is filled with air at atmospheric pressure at 20 $^{\circ} $ C. The box is closed and heated to 180 $^{\circ} $ C. What is the net force on each side of the box?    N

  Estimate how many molecules of air are in each 2.0-L breath you inhale thas*+ . dpciwxia6;2g; iflsap 2t were also in the last breath Galileo took. [f +c*giaplpw a.dx;2si62;si Hint: Assume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy ogj )jtmuoq b ,ees5(-(ro62z af an oxygen molecule at STP? m(q-bso), 2ree(zjjo tga65u   $ \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 temper+ t6hb4pr0 qynstn(/a atut/(h04nyprqs n+ 6ta bre of about 6000 K.    m/s

  By what factor will the rms speed of gas molecules increase if t9nn2z shfz6e,7uhk;v;jl og 8 he temperature is increased from 0,zl;f ngsnez82k; v jhh6 uo79 $^{\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, give,48v/syd njep n in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8,v 4 jey/sp8nd, 5, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules inweo56 qtt t7hcs9l. -t 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 doublejnu sv+v.9lk7 d while its volume is held constant, by what fal7s.j9uv vn +kctor does $v_{rms}$ change?   

Show that the rms speed of molecuizr c2zd+ko10a 8 tcc*les 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 tekpd*zvu-n:f/u/w i/va. ) vpumperature, the ratio of their rms speeds is equal to the v-z.)uvvnu /:p pui/f kwd/a*inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen molecules containedfo(t*9jntg o f u;(b/m in an 8.5$-m^3$ volume at 2.1 atm if the total amount of nitrogen is 1300 mol?    m/s

  Calculate (a) the rms speed of an oxygen molecule at 0 0yf3 n hg5no:iii)7(6vv ata r$^{\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 ni 7xajk t ayt8n3hfqle na)w.(,+ +d2pitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular mass is 8 z9m8rt4 vp rzp6g)kv .vp40on9 u in a living c t0r9v84n6)pv.k mvz 4oprzgpell 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 okq+fiexrkday hi2. t9:)zl.7f a gas 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 urattwcxvb4u 3y:5y m89knium, $^{235}$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, . eb8 nsy u r,h,a9;,lxwuvca2in 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 pres:yn) xde34e gdh9q9n(eoe)y qsure is 0.01 atm and the temperature is (a) q4 e9h edey:3gqd9 neo)(x)ny90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) jun 4hqo,c9-. dhiex- if the humidity is 50% on a day when the te4 i 9ndc- jo-hhe,qxu.mperature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water boils at 971ch 1ezr5*ig omobi /0 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is 0.72 atm, estimaxe.rb:ud/ v* -4u3 g(vbml yghte the temperature at whu4 d mx/vlru by-(hb.:g*3e gvich water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of water is 530 o nk.739 :dgtz pb(uflPa and the relative humidity isn .kl:tu( 3pb f9odzg7 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the6l ziv e)23se *ejs1xv*k 5bo (4dtcrx temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pre.)+g2yyq5j-cvqqq)e;j dg :f7y utf cssure cooker if the water is boiling at a temperaturyyqf+cgcq 2:) q jfq5ujt y-.e7 g);dve of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a roo-tyz6r*ne fz0m 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 l7jlysg.n0 ;op, b(r f5 $^{\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,vbzshul* *y6 glycine molecule (see Table 13–4) to diffuse a dista6*z, ysvuhl* bnce of 15 $\mu m$ in water at 20$^{\circ} $ C if its concentration varies over that distance from 1 mol/$m^3$ to 0.4 mol/$m^3$ Compare this “speed” to its rms (thermal) speed. The molecular mass of glycine is about 75 u. t $\approx$    s ([color=rgba(0, 0, 0, 0.85)]Round to one decimal places) $v_{diffuse}$    $ \times10^{ -5}$ m/s
$v_{rms}$    m/s

  Oxygen diffuses from the surface of insects to the interior through tiny t*2m*3, 1zoder5p us:zpq rqjnubes called tracheae. An average trachea is about 2 mm long and has cross-s5esdu z ppj123 zonqm*q*:rr,ectional 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 c9)tayx. 3/ hchkfy.wu alibrated 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 measuz+s mrn 9zjq iarr9/pggma2re) ,:v86re 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. Hop wh8f t *-*u7m-iksztw much error will be made in a recipe calling for 300 mL of cool water, if the water and the cup are hot, at 80pz-w-i f*uk sm*htt 78$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in nymn u -4rot:15 di+pfa helium gas cylinder is initially 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of the original gas remains in the cylinde1mor un:-t+4 fi pd5nyr?   

  Estimate the number of air molecules in a room of leng01) jlk r:cwmlth 6.5 m, width 3.1 m, and height 2.5 m. As:)w1ck0lrm ljsume the temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is about one atomi6 cpwj(:cmfnhal t,,,h h /j3 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 attfoxo;j ec k6r7uh(e7 m )v2h/xainable using the best available vacuum techniques is abox; 7 o/rxeh(f6huo2vecj )km7 ut $10^{-12} N/m^2$ 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 lumzhs9; ne8x+5e.xnm4/0j q vu aefo5ak(sr p( ngs to full capacity of 5.5 L when 10 m below the surface, to z+;5r x9/e(o(u.mqj smapsfn a450hx k8n eev what volume would his lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moon en r-0./dzqzywz (uka5y ters Earth’s atmosphere at a speed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this speed correspond to what temperature? (Because of this high temperature, the nose of a .a z/zzy( 0-krduy q5wspace 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 inlfvcrv+, v 0*vcreased 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 77i) f7 gqol vz3/tvhxi0w4tu 8lyz.*a90m$^2$ (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 valueplw (*by t6ix)w (5ojivb70lkef3v )v of atmospheric pressure at the surface of the Earth, estimate the total number of air molecules pibk)xb e 7t3lwof(i6l(5 vv )jvwy*0in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules cojz+poso; 6(97 v8 9xw9kqjtg5iuc ccbntained 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 oxnl 5/:nlpshe/b3axro *;dy;cygen used in a hospital has gauge pressure = 2000 psi (13,800 kPa) and le:a 3hb/5sxdn*nl ycr;p/o ; at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liquid mercury at 0e- oeur1jxbwkn t9* :7$^{\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 gasolintp3dedd,3 wtb8ze8 6zl ,vub3e 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 equatdi p-(,o-jugc or at 25$^{\circ} $C, but then was heated to 45$^{\circ} $C, how high above the Earth would the band be (assume equal everywhere)?    m

  A brass lid screws tightly onto a glass jstg vt++*c: op 8zfm 7ag :0yf51fdwehar 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 i,zjde*wz /aw 6n 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, hasa7kg w3vd iwmv+cs(./ 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 uc f*-5(c;e plbx i:qq kh0;njthe Earth is $ 1.12\times10^{4 } m/s$ so a gas molecule travelling away from Earth near the outer boundary of the Earth’s atmosphere would, at this speed, be able to escape from the Earth’s gravitational field. At what temperature is the average speed of
(a) oxygen molecules,    $ \times10^{5 }$K
(b) helium atoms equal to $ 1.12\times10^{4 } m/s$    $ \times10^{4}$K
(c) Can you see why our atmosphere contains oxygen but not helium?

  A 1.0-kg trash-can lid is suspended against gravity by tennis balls thrown vertio 4hukjaj6:mans29yj7/j*ws cally upward at it. How many tennis balls pe4 *m k6n9uj j/jssw2aa:7hojyr second must rebound from the lid elastically, assuming they have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameteia;6x jgu1-o sr (spherical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature is ix ao j6ug;-s1constant at 298 K, and the air behaves as a perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure in the air on the followin 1u vc74tp tfd-mod6vf:4k6ctg two days: tck4udf7:vf 4 1d tp-tom66 cv
(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 ironhu1/anw, s d3b at STP, and when it is a solid deeb ,h1/dnuaw 3sp 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 pressl6-i itwm-p ph.n+dr(kug- tg0-b.pb ure, the coefficient of volume expansion is equaugp- + -l .p.i6bkt m0bhw gidnp(-t-rl 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 deh; +kl.7x fmjmhumidify their cellars to prevent rot and mildew. If the cellm 7m ;ljk.xfh+ar 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