Which has more atoms: 1 kgbp m e8pcw1h.3 zunp*; of iron or 1 kg of aluminum? See the periodic table or Appendixnmpe *b8 3w.u;hp1 pcz B.

Name several properties of materials that could be e/ldfpr.i()lpb-fg gh (4, qvlxploited to make a thermometergp ,f4.l-/)lplvi( h grqd (bf.

Which is larger, 1 C :oplgk:.)s -go.)39 *rh xtc qeisnzs$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, b g9) ;m r6k,iiisznif1ut B is not in thermal equilibrium with symn;9 1zrig, s)ikfii6stem C, what can you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum r(hkoqcs *5l-( iyn/k:s aiym,iveted to a strip of iron. When heated, the strip will bend. Which metal will be on the outside ofk5qyi/( scn*(y-lo:, shikam 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 coefficient of linear e4fulx2x o9c2 hxpansion $\alpha$ 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 o moz2 .i q::::t hplmtp5- dg9nvdq+pff a simple thermostat used to control a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch is a glass vessel containing liquid mercury that conducts electricity when it can flow to touch both contact wires. nd:+tpglp :f:divmoq.tz59h mp q2: -Explain how this device controls the furnace and how it can be set at different temperatures.

Long steam pipes that are fixed wctlk-g4t (/ 8,fvdwb uj2u idz(hz..at the ends often have a section in the shape of a U. Wh./df 8d( b-g4,. vtk(zhuw 2jzcuwtily?

A flat, uniform cylinder of lead floats in mergoluq/bpyty w8;w 59y)e80s(3zucs rcury 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 y-ge00zm2wlw) 37 ketzvn zf7 in a hot tub of water, the mercury initially descends a bit and then rises.f2 k-0zgztvey)z7en0l7w 3wm Explain.

A glass container may breakn53w4el uwqi( if one part of it is heated or cooled more rapidly than adjacent pa 5l wwnuqe34(irts. Explain.

The principal virtue of Pyrex glass is that its coef,b nni v-6bl/bficient of linear expansion is much smaller than that f-n lvbn,6b bi/or ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurate atb 0x+hzqie70j- p93 h iskzwo 5)todrcl)c24w 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 sol6oolcp;y 7bb hv.ym +dd;-;kda will cause its bottom and top to bulge so badly the can will not stand up. What has hap7h.-ok;dd b;lbmylpo6;c v+ypened?

When a gas is rapidly compressed (say, by pushing down a piston), its temperat).ov5vo oui2: u3v/j)l uxex1hp+kvl ure increases. When akl +vo ovuxi )h p2/vuj :.l3)ovex51u 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 sphere submerged yn/y55iva 6auin water increase or decrease if uv5i65a/y naythe temperature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follopw1t1v1wp-toq ixa -i 47fk-uws from kinetic theory and the relation between average kinetic energy and the absoluvxti-t7- iuw1k4q1 1-wa ppfote temperature.

Explain in words how Gay-Lussa ,ums8bay(2sie7j-m ec’s law follows from kinetic theory.

As you go higher in the Earth’s a6oc6q6y9c rdi tmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth rtzkajl(eb8mf: (fr r0 l)i+hv9dl;x (efers to the minimum 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 (vbamz:8h lje9 fl+)(ix;( drkf trl0the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quitezq z 5y536ozs ki*covf8;x-ckly than water at room temperature. What can you infer about vqz; z ti5-*fo8s5 kzo6ye3x cthe molecular properties of one relative to the other?

Explain why a hot humid9a9p c2yvkj 58 0luibi day is far more uncomfortable than a hot dry day at the same tel 0ii2ckpa9jyu5bv9 8mperature.

Is it possible to boil wel0*rq z zb8.kater at room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the ai hdv xjy+m,:lj2 *tpw8+0brwir temperature is the same but the humidity is different. Which is more dense, the dry air or the x0pj 2w +iyj:lmrhb8wd, tv+* humid air at the same T? Explain.

Explain why it is dane099swtb) 47a bp gtxagerous to open the radiator cap of an overheated automobile engine7 )at4 pt0sbwxeb99ga.

Why does exhaled air appesisdu42s . +nhhc hyo2(;4pjfar as a little white cloud in the winter (Fig. 13–28)?

  How many atoms are there in7rwk f/or jxtdh e6-b o/bp/;c*q i9d: a 3.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare tvlc7/2uit5hp phz- l3 1wh +rno the number in a si/chli-nhlw 3u 2ptrp+75h1zv lver ring of the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this on the Celsius 1 +g/7ksul w7xvqivo.scale? w/k+. x7q1g 7svilovu   $^{\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 recorl e +)0zp7gusvded 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 lengtkq*ott l0)9clm g:c d+i(p zv7h 11.82 cm at 0.0:o*mtvq)tgd7k clp(z0+9i cl $^{\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 long (2n8bd)mcpo s2;(y2 hfl 0 $^{\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 apprz6 5d3ahh) /nslglo/joximately 300 m tall. Estimate how much its height changes between July ( )o/sl aj65nlhh/d zg3average 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, r y,l3b:c dkx.j d99g. 5fsucefivets 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 is to be placed in a hole 1.86j u. e ys5cd:.bdf ,3k9lc9gfx9 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 atgfyv5)c 4 mi+ru12lgv 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 innij *iia*,) nr8gar, 7a 0yx4o6k h cm3hbpva2 volume if it is heated from 30mak b3ahj a or ivry*,ihi0g7 a,2*n8c6x pn4) $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350.0 mL of wateczo;hm u:,ksdv a-p-.r 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 ,4eii qn2j nzh+ysd:uv;. -eh55.50 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 be placed in a ring made of ironj3;99nh0rp tm+ hv)hvl cd hfuu*4e1b. 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 contaig4r.d6i (f6ad;u jute.ea sa/ ned in a long, narrow vessel so it can expand in essentially one direction only, show that the effective coefficient of linear expansion is approximately equal to the coeffii; d.eu/sa(fja6a e46rt gd. ucient of volume expansion $\beta$.

(a) Show that the change in thximce(zja i,*jm4q3e +qi-/nld7c)gk b 5 pw*e 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 h3fv1,dg hxol) as coefficient of linear expansionold3 fx)v1gh , $\alpha$ 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, :phjoh i45gwpl5e 7;6lq hnm8$\beta$ = 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 clo*)i3yb.kmpvs ck is made of brass and keeps perfect time at 17 bp *3iv)skm y.$^{\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 men1y0p)evl tb7rcury thermometer has an inside diameter of 0.140 mm. The bul)lvypebn0t 71 b 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 radius hui3 j ab+4zsi7tw9- v0.41 m is rotating about itswv3 b7 taz-ij49+h usi axle on frictionless bearings with angular velocity $\omega$ = 32.8 rad/s If its temperature is now raised from 20.0 $^{\circ} $ C to 75.0 $^{\circ} $ C, what is the fractional change in $\omega$?   

  An aluminum bar has the desired length when at 15°C. 2gipdjzkkke gt8r,.(r 0) m0t How much stress is required to keep it at this length if the temperature inztkm0derk. k(pgt )0g r ji28,creases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of crosctetri2o-gy 02 ny8 b 9+dqll4s-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 134.12eu 0z.z*d.aqihe9pno 0q0v3z2 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 temperatures on t;q 2r pn5jc o1moj5tc6he 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 Fahrenheinaf0 a2a1im/ bps n9,ot scale?    $^{\circ} $ F

  Typical temperatures in the interioq z.ji;,0jjm 2 vs7;9 zeijisur 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 z9p )746tvb/ e.ze5 znkzr uqkat atmospheric pressure and a temperature of avrk6 .5 /qt)uzz7knzp4ze9 b ebout 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 n m/ )no/j40s6zmq:hug x hz0doxygen at STP using the ideal gas law.    kg/$m^3$

  A storage tank contains 21 dlem29jwldrqy(0207vhrf b 5.6 kg of nitrogen ($N_2$) at an absolute pressure of 3.65 atm. What will the pressure be if the nitrogen is replaced by an equal mass of $CO_2$    atm

  A storage tank at STP co . ,*ptx qtqze w,a/+-7ehcrhontains 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 ga*lszc( f 3ja7ls is at 10.0$^{\circ} $C and a gauge pressure of 0.350 atm, (a) calculate the volume of the helium gas under these conditions.    $m^3$
(b) Calculate the temperature if the gas is compressed to precisely half the volume at a gauge pressure of 1.00 atm.    $^{\circ} $ C

  What is the pressure b l23ey8 lr)ypinside a 35.0-L container holding 105.0 kg of argon gas at 38b)l 3lyr 2p8ye5 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg6t-v() xng3r1q l kfau 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 he 9nd- 05x*.etysjizyskzc.a: ating the air inside the balloon,-jazs c*di5ytx .ez ny0k.:9s which makes it less dense than the air outside. Suppose the volume of a balloon is 1800 $m^3$ and the required lift is 2700 N (rough estimate of the weight of the equipment and passenger). Calculate the temperature of the air inside the balloon which will produce the required lift. Assume that the outside air temperature is 0 $^{\circ} $ C and that air is an ideal gas under these conditions. What factors limit the maximum altitude attainable by this method for a given load? (Neglect variables like wind.) $\approx$    $^{\circ} $ C(Round to the nearest integer)

  A tire is filled withsfr.h-* tqk13wz :rim 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 pkx3.d5cke/ *a3pxaw18.0 $^{\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 s3 ol mxjwz2o80 lx6gno. c*4eescapes 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 numberdg h/7g1sz4p q31 37uiafcg bn of molecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1 hvsy)(z)ji jl/ nhy0gy8)0b9s1b kvi.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) mo( wb v5+udan+,is,tlo les,    $ \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. 21fcd,caucx6 +bu3v,b,,pc ez-sgcc1$ \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. mcsgm1hrum - y8ah2*90-L breath you inhale that were also in the last breath Galileo took. [Hint: h*hc 12 8rms9m-uaym gAssume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of an oxygen molecule at So 6xcq8(iel2wrs * wk8TP2*88 we6wl(rcks qoix ?    $ \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 Suyb(v. a1p ,c wbjo-h ;y*u3,1ho) qwvw8riaven at a temperature of about 6000 K.v p wwe1b- 8,w,a 1oh3vyr*q)yj; (buha.o ivc    m/s

  By what factor will the rms speed of gas molecules increau( 1y*/sc e.mjy-j hrc,f kk:cse if the temperature is incr(jm s, /k. ruy ccch-k:j1ef*yeased 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, gi zpivd 2:q)q 2lp59viaven in units of km/s: 6, 2, 4, 6, 0, 4, 1,vi 25l :)adq2qpv 9zpi 8, 5, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules3 b +4iaj 1vzl,lcz.wz in 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 constant, b-gh;iyhd:d2b-w 4iusp.f 4q k y what factor f i2h;k:pbqdghi- -yws4u 4 .ddoes $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is givvv)dzf7d7 rt:v 6r:dven 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 23e xc.: mdmnzof two gases at the same temperature, the ratio of their rms speeds is equal to the inverse ratio of the square roots of their molecular mm.ze: 3d2ncxmasses.

  What is the rms speed of nitroged w.6 dyjr8 a,n)ahgln llc9*;n 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 a b19pivrfb+x( ktdt81n 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 ob7cx(v+(vtf q87ty gbetween nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular mas + doxmp.2 lxlky(h.1ys is 89 u in a living cell at 3dllx+mox 2. .p1yh (yk7 $^{\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 ofvlqas v:v5irlff8 (z: 0y2 nk+07hgch 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 uraniumg7 aj7bm:ewz7 , $^{235}$U and $^{238}$U (the superscripts refer to their atomic mass), can be separated by a gas-diffusion process by combining them with fluorine to make the gaseous compound UF$_6$ Calculate the ratio of the rms speeds of these molecules for the two isotopes, at constant T.   

(a) At atmospheric pressure, in what phases ca +--2toic fpl/h1 l ;mhpcggpjw :(gn;n $CO_2$ exist? (b) For what range of pressures and temperatures can $CO_2$ be a liquid? Refer to Fig. 13–21.

Water is in which phase when the pressure is 0.01 atm and the for bu95 dpa1zrc; (wv67sb: rtemperature is (a) 90 rubr(97o:w5r;1z a v fdb6cps $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (a*mn4l( 9g+eensn (qi fpproximately) if the humidity is 50% on a day when the temperature is 25(lq *mn4ge ein+ (s9nf $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water boils at,+ (txnywkpfqnlv, 23 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the gbldxa u9b(r;s,3;vvo ;: fvjmountains is 0.72 atm, estimate the temperature abg;3b;vr,l9 j ax vo;ufvd :s(t which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of water is 530 Prlj ;la(vw0ne vd.bi10q*;a na and the relative h (.r0ja1 ilnvd0 w*;bae vn;lqumidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the temperak2:+jqt7q*u qml 9z rqture is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressur+tax4nzm(2 vce cooker if the water is boiling a4+x cv mntza2(t a temperature of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room tnt*v7zeb6b( 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 el4hs+gdy )5l5 $^{\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 a2p zbwp - eh1c-zri:lgs,gi)to3c/.wnq 7q/l glycine molecule (see Table 13–4) to diffuse a distqlw cq713b.lg w-on/pc e )hitprsz:/-,i g z2ance 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 interio/es96acpq:60l fui uwr through tiny tubes called tracheae. An average trachea is about 2 mm long and has cro:u96ieq 0cafswu6p l /ss-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 0 s n s1w,+e)z,uwa 8zlvz)uslcalibrated 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 meap s.n8pcn1w +a p(om;msure 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 tempevjz 83j xz28 -wx1 *g4moktkci6r, (ucqsmy4a rature. How much error will bqx ck jmsv 2t z41io 8(z 68km-gu,3rwyxc4ja*e made in a recipe 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 helium49y(lkp5ci pi fkn /h3 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 cylinder? 3y icflknhp p/4i9 (k5  

  Estimate the number of air molecules in a room of length gm4jxz/o,6 ma 6.5 m, width 3.1 m, and height 4a6 m,jmo/ zxg2.5 m. Assume 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 at ep1: dkwq00oqm 0q-3jyc.e nyga3li* om 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 attainable using the best available vacu:(oq2piy4o vmum techniques is about q:voo2 4(iypm$10^{-12} N/m^2$ 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;fis0c-p c6fw./x j h2, fzmdl his lungs to full capacity of 5.5 L when 10 m below the surface, to what volume would his lungs expand if he quickly rose ,d-.mfj;cf /zp l6i2sx 0wc hfto the surface? Is this advisable?    L

  A space vehicle returningoq 4l,z6r8 jxz from the Moon 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 correspond to what temperature? (Because of this high temperature, the nose of a space vehicle must be made oq8r x4o6lz, zjf 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 110 f yyec0++/wot$^{\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 77z/glz ffh0j+:0m$^2$ (a) What is the total mass of air inside the house at 20$^{\circ} $C?    kg
(b) If the temperature drops to -10$^{\circ} $C what mass of air enters or leaves the house?    kg

  From the known value of atmospheric pressure at the sudya*qh tf; 4c2rface of the Earth, estimate the total number of air molecules in the Earth’s atmosphere. 4t*a dfcyq;h2   $ \times10^{44 }$ molecules

  What is the rms speed ow hdu ljg;a-m,i18y1n5;oc vjf 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 used rwc/f,t.a va 0l/)pn hin a hospital has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the fhwap/)cr lat ,n0 fv/.low rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liquid mercury acd p6(-qocvx4,mxrpvgn .s/ )t q)m 6tt 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 gasolinks2, *ujktv 2i)z6mxce 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 tol v h;bq6y 6h.lyt,um ea+g)ep;+fgya* hq*a9 fit snugly around 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 d- 9 s4wrj0h+h )gzgstonto 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 in thes8kv, 9/ stmogf:o /cn 18$^{th}$ century, was a platinum bar with two very fine marks separated by what was defined to be exactly 1 m. If this standard bar was to be accurate to within $\pm1.0 \mu m$ how carefully would the trustees have needed to control the temperature? The coefficient of linear expansion for platinum is $ 9\times10^{ -6}C/^{-1}$. $\pm$ =    C$^{\circ} $

  A scuba tank, when fully charged, has a pressure of 1958-pst(r us7 tdio 5(dc 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 Earthc6rzwl0b . uw4 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;af -i4hic7/ t5yqp 7z6l: ew8kavmnt balls thrown vertically upward at it. How many tennis balls per second must rebound from the lid elastically, assuming they have a mass of 0.060 kg and at qzcwfmp 6;i4/75 vanht k liy7:8-aere thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter (spherical)qxx*(yy3ei 3c,5x l pb bubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the air behaves as a perfect gas. How large is the bubble when it reaches the ( 5qcxlx3,xpie *3yby surface?    cm

  Calculate the total wat21 -pwoyyzux,er vapor pressure in the air on the following two days: w 2p -xo1,yzuy
(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+o2(*jsa ljn43iu dzyja* +yfe:,wm y in the density of iron at STP, and when it is a solid deep in the Earth where the temperaturszal3 y* ejj(fu 2, miy4njwy +:od+*ae 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 cq:4 bwkybp0b 1onstant pressure, the coefficient of volwpqbb:4k by 01ume 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 constantlde7fypmhre29 7-ive+,c o q5i4 asn1 ey dehumidify their cellars to prevent rot and mildew. If tr14- i2 ,f7coaeqsvh+ eme5 9dpneiy7he 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