Which has more atoms: 1 kg of x7 u:punyky5 et5s/2ciron or 1 kg of aluminum? See the periodic table oy /2u5:kn7upetsx yc5r Appendix B.

Name several properties of materials that could bka w)-u95 snof2k/xks e exploited to make a thermometer.fks u-os9w2k an5)x/k

Which is larger, 1 C f4oigysud x9tf:w d7, t57t h2. mwg9t$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equh7 mht qp xg0f27jc()kilibrium with system B, but B is not in thermal equilibriumft2j0gcqk()p x7m h h7 with system C, what can you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted tc uf: 7sgkrb l vq*+i15rh+(csx0n:meo a strip of iron. When heated, the strip will bend. Which metal will be on the outside of the curve? [Hl vsu71kqg +sn :rbhxm(+ fc*:rce5i0int: 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 coeffici m 6bna6emon17pll1crt, q-5hent 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 con8w9wcp ../ 5 (lu*oook aieutx,q nv-ktrol 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 contact wires. Explain how this device controls the furnace and how it can be wktp8*o9 xu/5.,.eokaou(i wql v -cnset at different temperatures.

Long steam pipes that are fixed at the endx1e8-x.*z e (so v(s.vv, yj r)gugoums often have a section in the shape of a U. W 1oz8 sr)s,u- j.ue.gyv m(xxgv(e*o vhy?

A flat, uniform cylinder of lead floats in m*r kpe(ql ; mq((7sdlrnwk: ncy9-v4iercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-injx1e pmm. 6sher hpsno8 24r,7-glass thermometer is first placed in a hot tub of water, the mercury init,8pj26opm.e sm 1eh r7hr4x snially descends a bit and then rises. Explain.

A glass container may break if one part of it is heated or cooled 6irao.zs1 of gb,in( e+a wt:*more rapidly than adjacent parts.w r za +(.i*,6b1:saetoinfog Explain.

The principal virtue of Pyrex glass is that it2wbuy5k*1 k sys coefficient of linear expansion is much sma*y us25kbywk1 ller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurate at 2t64o93kytk v2pw / kqb0eaxa( 0 $^{\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/e,wu *dklp2 o i;unn5 will cause its bottom and top to bulge so badly the can will not stand up. What has uile* wn /kdo2u ;5p,nhappened?

When a gas is rapidly compressed (say, by pushing doaoxhxc xcv6x2 t (,c+n 7/5iuown a piston), its temperature increases. When a gas expands against a piston, it xc5 /(cn2 cx o7v+tiuhxx6ao, 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 sphere submerged in water,p+.d;+ozw sni m8r/w9l jd5yqi +hug increase or decrease if the temperatu8 dno+ld+/s9 ;ygrw, u +h.im5 zipjqwre is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theom9sagy 6 9b gwtd:m:(rdl *j;wv5frz,ry and the relation between averag, :wrlv ad m tb(dzgy *;w:fm969jg5rse kinetic energy and the absolute temperature.

Explain in words how Gay-Lussac’s law follows from kinet .ba8 x-wy)zfuic theory.

As you go higher in the 4bpt7g )ggiu xv:)f5bEarth’s atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the -2*::r0 iq kgmg wvmfaminimum speed an object must have to leave the Earth and never return. The escape velocity for the Moon is about one-fifth what it is for the Earth due to the Moon’s smaller mass. Ex0gfg2m-: rqaw*ki mv:plain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at rookga j9r;uv(ujw o8(,p: (ybq tm temperature. What can you infer about the molecular properties ofw;job:p(rv, 89qau y(( tug jk one relative to the other?

Explain why a hot humid dax*4jtyrznncbauw nk8(, k(q dm f8907y is far more uncomfortable than a hot dry day at the same tempnd*ak(8jnwckuxy ,t rf( m4 n8b0 97qzerature.

Is it possible to boil water at rdazot o1jqfp quud)3 k9rma6 63+ *y, m4pjkj2oom temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when t) bq5omuo-at64anuy d /h9y6 ehe air temperature is the same but the humidity is different. Which is more dense, the dry air or the humid air at the same T? Explainy-96yoh u mbano/64 auq5te) d.

Explain why it is dangerous to open the radiator cap of an overheated auto6dwu:ir vz3yh8be*g. mobile engiw.ri8*vz gu 3 :6dhbeyne.

Why does exhaled airsdo3 8ojq05 gq appear as a little white cloud in the winter (Fig. 13–28)?

  How many atoms are ther) 0wv)wi.zhu ke in a 3.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of ato 92 fueljj7(sg :f5qbjms in a 26.5-gram gold ring compare to the number in a silver ring o79bj e5sfuj glj (:f2qf the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken hq/rusk6lu+2dw au-d6 .b3jd;h z im0 to be 68°F. What is this on the Celsius scale?hi/2sk+l.abr-uzm66u ;ud 3jqdhw 0 d   $^{\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 adc l0gr4d0l: 6c9cddyre 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 at 0ih03diftg8p qnihd( n9x56b20c ;9 f) ltfb bu.0ihfdfg tc 3nhbxf0;b)8b2l it( 699qp n0d5u i $^{\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 istyy(fvj3,l+z x 9x ci; built 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 ofuu2h u.gv9:e +wc;dsl wrought iron approximately 300 m tall. Estimate how much its height changes between July (s9uh;ugl+d vu:c. e2waverage 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 tafegh;m*+ -- vvpu2gh han the rivet hole are often used and the rivet is cooled (usually in dry ice) before it is placed in the hole. v fm-h;a +vephu g-g2*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 da9y /+jm1 gmdat 4 $^{\circ} $ C is $ 1\times10^{3 }kg/m^3$ What is water’s density at 94 $^{\circ} $ C?    kg/$m^3$

  A quartz sphere is 8.75 cm in diameter. What will be its change in volgkp31h 8q8uf 1pqmi5so v )q)xume if it is heated from 30 sv)f8 1ghk o3xui1qm5qp8p) q $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the bri+xq a,h6sr 2b(b /qpv7 ude4pam with 350.0 mL of water at 100.0$^{\circ} $ C. If the temperature decreased to 20.0 $^{\circ} $ C, how much water could be added to the glass?    mL

  It is observed that 55.5+z8 0p7v8zey8fsr wi4vpw+nq 0 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 plaux mvj7,-ryep(z/qn 6ced 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 loniq61gizks f9ke6 ; )igg, narrow vessel so it can expand in essentially one eii9 q;6f6)gigz1kskdirection only, show that the effective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the uml 0,s. . ai1hfi,zxcdensity $\rho$ 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 l dhq.8 logi-l0+zxi2zength l and width w has coefficient of linear expansion xhq8.zg+ 0z olildi2 -$\alpha$ 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 sofjt;f)g 9p,y.i* n+8v sm nrsolid, $\beta$ = 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 madde/tjf1nx 7 (-p6vsrx e of brass and keeps perfect time at 17r6n/xps e7-(f 1xvjdt $^{\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.71x. p4jeih;yosl: yu The bulb has a volume of sj7lh:yiyx u.eo14p ;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 1aqhq*g6joq jvb29vlk4 (,a ycylindrical wheel of radius 0.41 m is rotating about its axle on frictionless bearings with angular velocityoaj ablqv*9 2 qv6q,kgj1(h4y $\omega$ = 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 15°C. How much stress iv fef9 ix+fyhx *3r43x ukw1l;s required to keep it at this length if th1x;y+3 x3vexkhfi9 *ufrl w4fe temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam ofsicufn+t q :5h9n(i 5u 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 w.qn* 10cqcaovjxec n(h0wkj : ,/sri4m0ys7134.122 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 followie*1 w2zjsry +yng temperatures 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 th up:yeuh 87)0hynddv 8e Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun are about 40ctct-j tk ;x3000$^{\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+:z54f lzi npc at atmospheric pressure and a temperature of about 20lfzcz4+5:npi $^{\circ} $C is compressed in the cylinder by a piston to $\frac{1}{9}$ of its original volume (compression ratio = 9.0). Estimate the temperature of the compressed air, assuming the pressure reaches 40 atm.    $^{\circ} $ C

  Calculate the density of oxygen at STP using the ideal gas 99ou-p1q hl1y- ivaanlaw.    kg/$m^3$

  A storage tank contains 21.6 k1vx8de+ a yb b1mai42mg of nitrogen ($N_2$) at an absolute pressure of 3.65 atm. What will the pressure be if the nitrogen is replaced by an equal mass of $CO_2$    atm

  A storage tank at STP contains 18.5 kg of nitr/l -5tsw nqgm6ogen ($N_2$)
(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 a8i,eq;;3(xhrwo xoav8 dcfj0t 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 kc/q2ga(30 k fead,za105.0 kg of argon gas at 3k/a2a(,qdzkcf e3 0ga 85 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg o ,y;gy g8kj0(yh oxl4kf $O_2$ gas at a gauge pressure of 8.70 atm. If the oxygen is replaced by helium, how many kilograms of the latter will be needed to produce a gauge pressure of 7.00 atm?    kg He

  A hot-air balloon achieves its buoyant lift by heating the air inside the.pgo+ q 1dh5zz ay-q2f balloon, which makes it less dense than the air outside. Su h qfg 5+1-p.q2oyzazdppose 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 ai(fss3 -0smjup-z tak 6r 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 18.0e5fr+jq,e: eyww/ xw 8 $^{\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 esc8ut lsh uu,xs25snd/ 5hw8s x6apes a child’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 molecules /okhdn.j ;+j50 mjpk (g $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How many moldl h460*jvostvh -hf)o5e;ls ecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) molj*5ywoafae -3.rcyw1e5ze o c24 q;qhes,    $ \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 5p 75 (v+s76 ewfudsihn.1$ \times10^{ -2}m^3$ is filled with air at atmospheric pressure at 20 $^{\circ} $ C. The box is closed and heated to 180 $^{\circ} $ C. What is the net force on each side of the box?    N

  Estimate how many molecules of air are in each 2.0-L breath you inrxh83f+,z ktbf7 7s omhale that were also in the last breath Galileo took. [Hint: Assume the atmosphere is about 13sk8 zxb,7 f7fmho+tr0 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of 79kuwd1 fmn*vefx w x v)c.89gan oxygen molecule at STgv7dfm9x kv)cfeuwx n . 19*8wP?    $ \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 sur*+lgldrk jv/ + (yx)jbzku4 542sck v,wc wzs1face of the Sun at a temperature j4 cz*rsk k5d/ ycvwj2,l 4l+(vwz)sbg 1kxu+ of about 6000 K.    m/s

  By what factor will the rms speed of gas molecules increz)9luaich/2 j3k/ 9z hoahd5nase if the temperature is in 9kh) hzi/h/za395o dljn 2ucacreased 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 units of km/s: 6, 2, 4, 6y7j7tq- e 7nhsfczh-r6 5ksg,, 0, 4, 1, 8, 5, 3, 7, and 8. Calculate the ,7k7 fne t-6 cqzrjs-5yh7 gshrms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas a2q:y:,rcfi am t 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 whit8t w// ko hhp6ahhjwf 8.90qwle its volume is held constant, by what factor 08kww/9p 6thajoq h8whh/.tfdoes $v_{rms}$ change?   

Show that the rms speed of molecules in+-a :ujkjj;jt 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 temperat:kgb p3a7,m8 se)-mi3zo:lgi f q/ upjure, the ratio of their rm8l aksg7 mm j q-iuopf,i3e3bg)/:zp:s speeds is equal to the inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nit+oaug 7 8pof3krogen 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 oxygen mov/cm*v7jqc6 soh/ct e9z7p +/ ymq.rb lecule 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 distancwpo:ro hw5 x39uz h7z:e between nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular mass is 89 u in a-bnu9wy n tuvd0u.a)1 livinvund.t0 b-1u) w9ynua g cell 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 gas can .dh)tos 9:1hqt .bz9m6.lrwtnp.roobe 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 t mqbm2j q)/eg*c; i6xuranium, $^{235}$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 pcdvvn 8244 wloapctz( j8wn 39vo- 1)kjq ous1ressure, 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 thear / f4awghyz8 u4n;0m temperature is (a) 90 hmg4;8n farwa z4u/0y $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (05b wx9-en0gg4olhzc qk m n1:a vg*2papproximately) if the humidity is 50% on a day when the tempa0-k w21lgg pxqb5n*m echvz9n0go: 4erature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water boils afm*pi4e-(g2 dv; zty zt 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mouynlh27y ;yla- ntains is 0.72 atm, estimate the temperature at wh an7l-y y;y2lhich water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of watef qp)t,9s .qxlr is 530 Pa and the relative humidity is,fx pql9)st q. 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day 2d.m5grkk szw5x 8ch/ 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 boil s;syasq*t4yp.iqix ;u- t r39ing at a temperature of 120 3 .sas ty*iuy-;qt4i s;qrpx9$^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a c/t2yg*t24htf+e7hn le 9nn j room 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 p6imm4 go et1w5*l(53kh khlskoint of 5 $^{\circ} $ C is drawn into a building where it is heated to 25. What will be the relative humidity at this temperature? Assume constant pressure of 1.0 atm. Take into account the expansion of the air.    %

  Estimate the time needed for a glycine molecule (see Table 13–4) to diffuse *gcud2j kahe9 3n4:bna distance of 192a*:cegb 3nhk4jun d 5 $\mu m$ 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 th87(1sty+kqxd25nzsd2 b*s hj1 nxooce interior through tiny tubes called tracheae. An average trachea is about 2 mm lo1d17szbk2c ns 2xqo nh t+d xj(*8soy5ng and has cross-sectional area of $ 2\times10^{-9 } m^2$ Assuming the concentration of oxygen inside is half what it is outside in the atmosphere,
(a) show that the concentration of oxygen in the air (assume 21% is oxygen) at 20$^{\circ} $ C is about 8.7 mol/$m^3$ then $\approx$    mol/$m^3$(Round to one decimal places)
(b) calculate the diffusion rate J,    $ \times10^{-11 }$ mol/s
(c) estimate the average time for a molecule to diffuse in. Assume the diffusion constant is $ 1\times10^{-5 } m^2/s$    s

  A precise steel tape measure has been calib1w,b6eeuvm a 3rated 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 measur k 06m1m)r(+k-k 8u +falepyqzp gpa0te 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 temsbo h6 vj w,nm9s3tx*-vesm++perature. How much error will be made in a reciph ojswt bvs3x+n+me, 96*sm-ve calling for 300 mL of cool water, if the water and the cup are hot, at 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in a helium gas cy 9xqns e6u29iq l(b*p g0ox j4p*;pprhlinder is initially 28 atm. After many balloop9 (sp6url gq;oe 04b*ij*9xqh pn2 pxns have been blown up, the gauge pressure has decreased to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air molecules in a roo71h- o j7nb2cg3yz lnkm of length 6.5 m, width 3.1 m, and height 2.5 m. Assume the temperature ibcg k7n2hl7nozy-1 3js 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of mattb vgabyjbt)xge :8 ;+;ux w(;ter 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 attainablei)zmst .tqa*1 using the best available vacuum techniques is aboutt.1* )sa tizqm $10^{-12} N/m^2$ 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 whensx/ a*hf+pjl6:)9cyhtisl zj tk7xaev71a .7 10 m below the surface, to what volume would his lungs expandxjisj 77h9k)lt.t s pevc+xa6 17fh/l*zy:aa if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from in -fpmf4 1dxgc 3r7h q(7n1qdthe Moon enters Earth’s atmosphere at a speed of about 40,000 km/h Molecules (assume nipf3gr n4n7d dx1ih -c(fqq1m 7trogen) striking the nose of the vehicle with this speed correspond to what temperature? (Because of this high temperature, the nose of a space vehicle must be made of special 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 increased from b;xj oykzap+/7(m( .(m awvgd110$^{\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 volumemkf(mv k(n6 n8 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 sl mly-tj.gy*( ih8e.s-3lcvof atmospheric pressure at the surface of the Earth, estimate the total number of air molecules in the Earyji8(l*s-e.3-y hll tg.c sm vth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen moleculeb 9cepe 9qti1cltu 9gt/(ce2l-w he 68s 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 us1y 7g:8xwgl4 z1 dm ivcnny-)1ck 4zgped in a hospital has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric cgx )pz:dy1 4w4gcnzi1yl1k8vn7g -m pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats inh7q; d xdj:9yz7ohiz h ,y51ss 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 0j0l(tf (q q5q(f8solnh e(kwr: k4q+k$^{\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 -/6ag zc7ihls the Earth’s equator at 25$^{\circ} $C, but then was heated to 45$^{\circ} $C, how high above the Earth would the band be (assume equal everywhere)?    m

  A brass lid screws tightly ontoohjmqt/qz/ 188kn8jq q, 4nwf 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 standard, adopted e-+:zr.g;j-sd imiqbolvn.kr( - l- hin 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,kpwn pm4hy23xvv*v p90gn4 p) 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 Eartb( xjy; 2p vd*4yx/axcr;q c9ih 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 suspo u0yvin0ai0x7z 2 :ayended against gravity by tennis balls thrown vertically upward at it. How many tennis balls per second must rebound from the lid elasticaa:7u0o00an y2iz vxy illy, assuming they have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter (spherical) bubble of air from a h-*u2:5usny98 zipg uauno c/depth of 14.0 m in a lake. Assume the temperature 2-c*9guu8:z5 nyhiousp/ nua is constant at 298 K, and the air behaves as a perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure in the -cn,9xa tbz)4 z+vumg air on the following two days: 4uzaxt+n) v, b-z cgm9
(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 diff)sv aw 5r6dq/xerence in the density of iron at STP, and when it is a solid deep in v6xsq)wd r /5athe 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 consxf;osuz *ft :j .q7i*otant pressure, the coefficix tz7:us.* of*;j oiqfent 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.

  In humid climates, people cons) ;(3xo,efv;xk/bpbpr- )nd : cthg actantly dehumidify their cellars to prevent rot and mildew. If the cellar in a house (khon gve,bpdrx-x;(cbpa/;3:k)f )ctept 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