Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodichv.43qq2scz v table or Appendix vs4h.qvq c32zB.

Name several propertieaw yo5 p2o d9ak/crgo4p 08c+ds of materials that could be exploited to make a thermometer w 5c d/o9c480dpgpyok2a r+ao.

Which is larger, 1 Cc vo+d-ucv-3g hmal * 6ug7kf- $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equ)56: xg jltkqdilibrium with system B, but B is not in thermal equilibrium with system C, what can you say about t56qj:t xkg)dl he temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted e *vopd83hg(9u:rbdj to a strip of iron. When heated, the strip b 8v(ur*d: h39 egdjpowill bend. Which metal will be on the outside of the curve? [Hint: See Table 13–1.] Why?

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

The units for the coeffib /jskvc/5tv) cient 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 thermostatb o j 1j/yci3ik3b*q1c 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 switck iqj3cyi/cjbb13o 1*h 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 fixen 3nt7zvlxzybi3: 3 ki*ycm7,d at the ends often have a section in the shape of a U.:kyt i7n3,lzcz 3x nv37 myi*b Why?

A flat, uniform cylinder of lead floupr0 vqjgz1 rud:2 n711odbg3ats in mercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometer is first placed in a hot tub of 5 aok4pf8di*lq zv4(m7u 6eeye7q l 1zwater, the mercury initially descends a bit lfdo y6ua415v4e8i*me 7q(ez7pq lk zand then rises. Explain.

A glass container may b8- i9gtay,qh yq )p9qpreak if one part of it is heated or cooled more rapidly than adjacent 9)8aqy,qptih y-9 g pqparts. Explain.

The principal virtue of Pyrex glass is that io. cs(ww-m2xtts coefficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives ris.(-x2msowwct e to the increased heat resistance of Pyrex.

Will a grandfather clock, acp/pa6z5g6pcn g-wp5 vcurate 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 cause its bottom and top to bulg2 (gmb*hajhba cdc8g 4n )65lle so badly the can wil c 5dm8agbc an gl642(ljbhh)*l not stand up. What has happened?

When a gas is rapidly compressed (say, by pushing downa eh(7dd l2w+r a piston), its temperature increases. 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 strhr 7wla( ed+2dike the moving piston.

Will the buoyant force on an alu(ux 7hfr* +s5vy7npeb minum sphere submerged in water increase or decrease if the temperature is increased from 20 (*vbsn5fh 7+e xu7yp r$^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theory and the r0 d09,h glrkfjelation between average kinetic dg h,rj0lf9k0 energy and the absolute temperature.

Explain in words how Gay-Lussac’s law follows from kinetic t t2aikfxj l92m6w; i(theory.

As you go higher in the Earth’s atmosphere, the t7z ),avvi ,jiratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for t6 x:xh:at1wap he Earth refers to the minimum speed an object must have to leave the Earth and never retxw6 tax1p:a: hurn. The escape velocity for the Moon is about one-fifth what it is for the Earth due to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more qu0 ue1,fgou/ url-wr1d-obja; ickly than water at room temperature. What can you infer/u1ofb -r0;ldo1uu r,gae wj - about the molecular properties of one relative to the other?

Explain why a hot humid day is far more uncomfortable than a hot dry t87 zrn1-17hek atr zmday at the same temperatu8 h 1mr7trt-zkza7e n1re.

Is it possible to boil water at room tempera /yo iaa,zlt d5i+l+sa-8 z tk(l.;h ofhbdp74ture (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same:r 3fogk)w.y g but the humidity is different. Which is more dense, the dry air or the humid air at the same fg gy:.w )3okrT? Explain.

Explain why it is dangerous to open the radiator cap ofi t))xpa;w y;ylx2pq1 an overheated automobile enginixpq )lyypa)w1 ;2x t;e.

Why does exhaled air appear as a little white cloud in the winter i/i 3,t(zbj+8rdpes5wxyz v9(Fig. 13–28)?

  How many atoms are there in vj1yv uv8 +a63n+zkp ga 3.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram kkk.zs0 .5wbmime(gj ec;y /-k,j/hqgold ring compare to the number in a silver ring of the same ma;ckm/egk.zs(/ iek-.0 hbjykjm5w , qss?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is v *naw8q9 oij-vt*yp-this on the Celsius scale?jv-- *aqy 8 w9ipvn*to   $^{\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 lo2rs98 wg hl-imwest temperatures recorded are 136 $^{\circ} $F in the Libyan desert and -129 $^{\circ} $F in Antarctica. What are these temperatures on the Celsius scale?high =    $^{\circ} $ C
low =    $^{\circ} $ C

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

  In an alcohol-in-glass thermometer, the alcohol column has civfz0k ,:8 zypbh xdz-.5:xtlength 11.82 cm at 0.0pi 0 xh.bz5:tdyz,z kx:v 8c-f $^{\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 o;vu2(s j5;of3 t x;wo eb7-njefm1je m long (20 $^{\circ} $ C). How wide should the expansion cracks between the slabs be (at 20 $^{\circ} $ C) to prevent buckling if the range of temperature is -30 $^{\circ} $ C to +50 $^{\circ} $ C?    m

  Super Inva$^{TM}$, an alloy of iron and nickel, is a strong material with a very low coefficient of linear expansion [0.2$ \times10^{ -6}$(C?)$^{-1}$]
A 2.0-m-long tabletop made of this alloy is used for sensitive laser measurements where extremely high tolerances are required. How much will this table expand along its length if the temperature increases 5.0 $^{\circ} $ C? Compare to tabletops made of steel.   $ \times10^{-6 }$ m    $ \times10^{-4 }$ m

  The Eiffel Tower (Fig. 13–29) is built of wrought iron approximately 30 fn 4-0kmcbzd/0 m tall. Estimate how much its height changes between July (average temperature of0-n/4 fkz bdcm 25°C) and January (average temperature of 2 $^{\circ} $ C). Ignore the angles of the iron beams, and treat the tower as a vertical beam.    m

  To make a secure fit, rivets that are larger than the rivet hole are often us )y tij.fp v x0qp f7gs*a-ad99s7wpc6ed and the rivet is cooled (usually in atvxqs) * 7w.96fjsyip-dp cpf79ga0dry ice) before it is placed in the hole. 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 apf,8z ;1xuy. krm (9 o.s3k1dnnsjwmg t 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 i)fb5gl ron+s: n diameter. What will be its change in volume if it is heated o5l):sgn +r bffrom 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled tv/l ,fi)c- xvau +7eejo the brim 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 55.50 mLwtbb+g or*-6c 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 iron. At 201c*asa*x:r q2rktn pl e7v ooxm(p3 :0 $^{\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, narbb9wf;zl t-0 nrow vessel so it can expand in essentially one direction only, show that the effective coefficient of linear expansion is approximately equal to the cwbbn f9;zlt 0-oefficient of volume expansion $\beta$.

(a) Show that the change in t9r o xyh hx17hz363cvlhe 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 anv m(2t q/l;ziulour2;d width w has coefficient of linear expansion ; mvu; uzi2lq/tr(2lo$\alpha$ 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 isotropip) ac72m u8j7jl,btkh c solid, $\beta$ = 3$\alpha$ if the amount of expansion is small. $\beta$ and $\alpha$ are the coefficients of volume and linear expansion, respectively. [Hint: Consider a cubical solid, and neglect very small quantities. See also Problem 18 and Fig. 13–30.]

  The pendulum in a grandfather clock is p0nsuq.jo 8 o*7doxs 0vx3p+ bmade of brass and keeps perfect time at 17 bns.p0ox3o* j8q pus 7o0v x+d$^{\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 insiwmx6g y/6i.f v3jg f/ide diameter of 0.140 mm. The bulb has a volume o imif.jxgvfg3/y 6w6/f 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 cylindric 0fmnp7- v,qom 2 3yrk+dqd7xral wheel of radius 0.41 m is rotating about its axle on fric0ydq-rr,p mmdx7k n7vf23+oqtionless 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 +inb5hfbz0tck(9 0i gwhen at 15°C. How much stress is required to keep it at this length if the temperature increases to 3 f9bcki0tz 0(gbhi+n55 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam ofmhb pki/4jt;f5 70ezl 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 134.122 cm atf gx7qt2ovc6; 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 tem:-jos,c 7kk vd4bj5 eni;axc /peratures 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 thsr 3plb nxpcib:7,jdv+9xf91 e Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in t 2zdi,sb1+qwa5auzx j do*4a1 he interior 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, aint ljr qdx:*dyp o lpu5v8*;61r at atmospheric pressure and a temperature of abd p lj *px5 tol*61yn:qv8;durout 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 the ideal gas lawd4ek+ma ks(8qh q-rk.dzzn-* .    kg/$m^3$

  A storage tank contains 21.6 k.4s,wrw,jbmld )vqx hn0gr. 3g 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 contai543kufgn v8n hns 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 gaso 5n z2cz6 z,9(dnbx f8mhy3pv is at 10.0$^{\circ} $C and a gauge pressure of 0.350 atm, (a) calculate the volume of the helium gas under these conditions.    $m^3$
(b) Calculate the temperature if the gas is compressed to precisely half the volume at a gauge pressure of 1.00 atm.    $^{\circ} $ C

  What is the pressure inside a 35.0-L container holdingh5l) 5fy3 qi x*gkx t:ig,gel6 105.0 kg of argon gas at 3853tkiy*i 5 hg,lqxl:e)xf5 6gg K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 9c (nwi,8y zclkg 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 heatingrd .k(u n6og7-3 wsksns*ble:4d zvn2 the air inside the balloon, nn 7(k bv r2 s3:nezlwk*d.odg6-s4us 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 with air at 15ice d )r1)hrg7 $^{\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-scxo qymbw*7puy 1:7 :92rnh cilve8 18.0 $^{\circ} $ C and an absolute pressure of 2.45 atm are compressed to 48.8 L and at the same time the temperature is raised to 50.0°C, what will the new pressure be?    atm

  A helium-filled balloon escapes a child’s hand at sea l(ryizpu* 2r- kevel 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 ofc gj 9i glnd*cz5,w vt),a6h,t molecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are theh ij02v09n 1ha2xwii qre in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) moles, (s.ukvl ppl keo123m+   $ \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 volumes23k) d/pfuowyq/m. nb5 *voagi4z t: 5.1$ \times10^{ -2}m^3$ is filled with air at atmospheric pressure at 20 $^{\circ} $ C. The box is closed and heated to 180 $^{\circ} $ C. What is the net force on each side of the box?    N

  Estimate how many molecules of air are in each 2.0-L breath you inhale + 9lxfasop4.:: x-elqvk1jmpthat were also in the last breath Galileo took. [Hint paq-m :flve+.p 914 skj:xoxl: Assume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of an oxygen molecule at *9n/fe b .u,cw+jde jvST/, bvc*uj +. enfdw9jeP?    $ \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 buv)ne0x wh1s2saq15 of helium atoms near the surface of the Sun at a temperature of about uabss) 5ehw1q1nvx 026000 K.    m/s

  By what factor will the rms speed of gas mo+wm5r* gkl(hw h/ij7 1a vnilkh: n5t1lecules increase if the temperature is increased fron(wh i:ig/ll 7a1n w5hk51krmt *vh+jm 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 ox cov9r*y5t:speeds, given in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calculate the rms speed. ry c:vt9*o5xo $v_{rms}$ =    km/s

  The rms speed of molecules in a gasnal*c q +(lw82ihuh. li 9n *tjyq*s1t 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 heldgy zu7cqs(8c+ constant, by what factoc+u(gsqcz8 y7 r does $v_{rms}$ change?   

Show that the rms speed of molecules3-d rb1 nj4pmp 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 mixturf8w+ou9i dqgq nk7.0uo (p6c qe of two gases at the same temperature, the ratio of their rms speeds is equao uq9g+(6qc8o.0i dq7 wkupfnl to the inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen molecules contained in a j+.-bo3cpgy tkj-u o9n 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 oa) dp k4nh57dkf an 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 be0ka)p5i8d p (zfqgax48eio /qedb-/dtween nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of annzxpj:rv km;:8aq8o 9p87n sz amino acid whose molecular mass is 89 u in a livx9sn q:z78r;:jz opv8 kamn8ping 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 ca.f vup.3v8 lra5vgn:fn 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 uranium,f4 x5 k0yhfn0 -bvwjw.lzbkd949al m, $^{235}$U and $^{238}$U (the superscripts refer to their atomic mass), can be separated by a gas-diffusion process by combining them with fluorine to make the gaseous compound UF$_6$ Calculate the ratio of the rms speeds of these molecules for the two isotopes, at constant T.   

(a) At atmospheric pressurepi00pw- x 68re2orrde , 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 phazpb +)byng3hv 1zr10b se when the pressure is 0.01 atm and the temperature is (a)zb+ nb)01hvz3pg1y r b 90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew pointa++pvhcp2g3b (approximately) if the humidity is 50% on a day when the temperature is 25 3+gbp a2 vh+cp$^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water boilfvuo4pep0pi 1 ix v8vc;.lz:7s at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particutr0 ewj5/;r iclar place in the mountains is 0.72 atm, estimate the temperature at which water boilse0t;rc5i/j wr. $\approx$ =    $^{\circ} $ C

  What is the temperature 9-)f ;l vampi:ci;g /lbuc i-p8 m.pxeon a day when the partial pressure of water is 530 Pa and the relative -l.cx;bva /gpc m9)8iul;ef- pipmi: humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the temperature vv-wn)mz pe0+:ld4khis 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure c,lp5gdv7 9 po8qai4vc ooker if the water is boiling at a temperature of 120 qc ,p i89pgvo5lavd74 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room of volu.4m ,vng skw1exf er5fwx*x ahl:8kj 035mn0bme 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 p;b.+*fmyo sdp 4t/b ewoint 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 myk c0c 0rkdu -ki,0ucop,d44zolecule (see Table 13–4) to diffuse a distckdki0-upcy u0d4 ko0c,,z 4rance 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 thw9p k4cf)65g ue//54ixq *fnzv wwqprrough tiny tubes called tracheae. An av nifq 4*)f vwg p 9zxek/w56u4prq/cw5erage trachea is about 2 mm long and has cross-sectional area of $ 2\times10^{-9 } m^2$ Assuming the concentration of oxygen inside is half what it is outside in the atmosphere,
(a) show that the concentration of oxygen in the air (assume 21% is oxygen) at 20$^{\circ} $ C is about 8.7 mol/$m^3$ then $\approx$    mol/$m^3$(Round to one decimal places)
(b) calculate the diffusion rate J,    $ \times10^{-11 }$ mol/s
(c) estimate the average time for a molecule to diffuse in. Assume the diffusion constant is $ 1\times10^{-5 } m^2/s$    s

  A precise steel tape measure hxb ::dn n /p ri2t71+avyz3zfnas been calibrated at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A precise steel tape measure has been calibrated at 267vq. yys d4 u5jsibw-0$^{\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 nbzd4um )x hm ))jr43xawcuzvc*, ;ks0ormal room temperature. How much error will be made in a recipe calling for 300 z msrxh0*)cvxcu)mw3 ;4u,a j4)bzkd 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 ,c m l-tw0.ck,oqsu g +.7zjlegas cylinder is initially 28 atm. After many balloons have been blown up, thel.,.u oglc07jqemts,cwk+z - gauge pressure has decreased to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air moleculeyy ecr 2sng e)h)h .5mu.1lw)hs in a room of length 6.5 m, width 3.1 m, and heightr5ly1 .snewh2 y mh).)gec)hu 2.5 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 o+ kb wk bk1bmo2x93h fqa9dv16ne 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 a4 ynflho );sgg 9dfe; dl+g.w+b4v0 edttainable using the best available vacuum techniques is aboutgf44wdv+h y s)0 ;e.d;fo9gleb+ndgl $10^{-12} N/m^2$ 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 fu, 2:djpd(qj qzll capacity of 5.5 L when 10 m below the sjq2:(jz ,dd pqurface, to what volume would his lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returh87;17 vynpktei ;von 7 r/cqaning 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? (Becaus7io;h 8rpvk;vt1q /nan y7 7ece 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 10c( wy; ql5oh/nwt8y r22 gcyz10$^{\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 77b rz; 1 gs+6ef;o/teyz0m$^2$ (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 valueakh agh6kx 6:m1ir- (n of atmospheric pressure at the surface of the Earth, estimate the total number of air molecules in the Ea(6:6g- hmairxkak 1hnrth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contained in a 7j:1bp)ltv rg b1lcx 10.6$-m^3$ volume at 4.2 atm if the total amount of nitrogen is 1800 mol?    m/s

  A standard cylinder of oxpuewtb pp7 95 1j)ufw9ygen used in a hospital has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long w fwptpuu59jw p1e 9)7bill 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 obdsl /ftwv0 7m2n v6rm.vi75hf 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 gasolig mqjr59r6dk r4y/0i tne 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 e (f/ .dt -t4hr-.acmzhqf0s xfit 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 onto wb8 :c0i 93+ct3ntr hjoc(s:bjj9cgz 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 standardatfq:nolns.* :cb 5f), adopted in the 18$^{th}$ century, was a platinum bar with two very fine marks separated by what was defined to be exactly 1 m. If this standard bar was to be accurate to within $\pm1.0 \mu m$ how carefully would the trustees have needed to control the temperature? The coefficient of linear expansion for platinum is $ 9\times10^{ -6}C/^{-1}$. $\pm$ =    C$^{\circ} $

  A scuba tank, when fully charged, has a 5-e zt( hvm;t6 mdvxe+pressure of 195 atm at 20$^{\circ} $C. The volume of the tank is 11.3 L.
(a) What would the volume of the air be at 1.00 atm and at the same temperature?    L
(b) Before entering the water, a person consumes 2.0 L of air in each breath, and breathes 12 times a minute. At this rate, how long would the tank last?    min
(c) At a depth of 20.0 m of sea water and temperature of 10$^{\circ} $C, how long would the same tank last assuming the breathing rate does not change?    min

  The escape speed from the Earth is x0ep ls/l gd(kg 6x,3e$ 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 ao 0ru4ro9.om(an,wkv gainst gravity by tennis balls thrown vertically upward at it. How many tennis balls per second must rebound from the lid elastically, asrnwkur(.m0ao v,o9o4suming 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) bubiwlk9h( n/r3f-vu fr (mo9+6m z7tcgbble 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 ikbnumg(r/f h(f9ivc z l36tm+7r9w-os the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure in th t.qyi7d +bp;ce air on the following two days: y7dibt;qpc.+
(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 iron at STPgwd -bu-d;yo. , and when it is a solid deepub-d-;y go wd. 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 gtlt0d zr2 ;(skas at constant pressure, the coefficient of volume exps2 t rtkzl0(;dansion is equal to $\beta$ = 1/T where T is the temperature in kelvins. Compare to Table 13–1 for gases at T = 293K (b) Show that the bulk modulus (Section 9–5) for an ideal gas held at constant temperature is B = P where P is the pressure.

  In humid climates, people constantly dehumidify their cellars to ihqz.3azk eq:8 m 64q)lsu3uzprevent rot and mildew. If the cellar in a house (ke 4mq3l)k6i83z :zezu ash. uqqpt 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