Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periors/- z:c rwe +pn2lv2a3 qjcx(dic table orr2-pslac je+cz: (x 2/nw vrq3 Appendix B.

Name several properties of materials tha jish;0fdhb3are3x7- ej/ 1/h7hq vv yt could be exploited to make a thermometer.y0h hqhs-ah3id7/ 1x ;73j v erjbvf/e

Which is larger, 1 C ncccj,zo27e .h6zzy k0/wbv1 $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B ivp g/v2)h /bbwcme. i8s not in thermal equilimghb) c pv/8bwv.i e2/brium with system C, what can you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to a strip of ironl*izznjms l:sk6,j ;o5*h2 tt . When heated, the strip will bend. Which metal will be onkztn:2;z5l ,j lo6hss *ji t*m 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 cosytxvaask 5r2n.8 6k1efficient 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 simpleo7 u 6, 2oyo k.v:bwivd,ghxq/ 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 i,o qy6ovb, oxug/kd2v.w:h 7 liquid mercury that conducts electricity when it can flow to touch both contact wires. Explain how this device controls the furnace and how it can be set at different temperatures.

Long steam pipes that are fixed at the ends often have a section in 7uivlm34(a m jthe shape of aumm(3 il7v 4ja U. Why?

A flat, uniform cylinder of lead floats in mercury at 0ml7 px7 2bo(ml 4lx,gc $^{\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 water,5vn9u tgfl7e9e49ze0 tk/v ,w0sd klx the mercury initially descends a bit and then rises. Evedtn 479/5t00 k g ex zsel9fk,l9vwuxplain.

A glass container may break if one part of it isv:p-d7poqjn kq0,;k x heated or cooled more rapidly than adjacent do ;pq 7,:0q -pjxvnkkparts. Explain.

The principal virtue of Pyrex glass is that its coefficient of linear e kq+g6hwtu rh0u d9l +i;9(ahexpansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased;uweduirhh t+l0 99hg+kaq ( 6 heat resistance of Pyrex.

Will a grandfather clock, accurate at 205 kj*j 0u()aqafk*zia $^{\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 bulge so b;g94y qcicln aa7r3e )8jp9j vadly the can will not stand up. )7l j y vq8ig3j4rnapa;9e9cc What has happened?

When a gas is rapidly compressed (say, by pushing down a piston), its0gt930 f9, da/ oi7agry pk4w/gyyqci 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 ty7d0arpiyy/3i 49gkw 9,gfqocag/0t o the momentum of molecules when they strike the moving piston.

Will the buoyant force on an alu, b0nb*,d7qi(qhj oe zvmy77rminum sphere submerged in water increase or decrease if the temperature is increased fromhey j77vd(* m qnqor70 bzi,,b 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theor 0ikt7u*wbq2( y9 ghig;+h8fqlkhg6x y and the relation between average kinetic en62k*q 7bgt yhf;hk(0g8xwq+i iu9lhg ergy and the absolute temperature.

Explain in words how Gay-Lussac’s law follows from-bl w/-* z/s 5qmq41n/9pfaklnpvetx kinetic theory.

As you go higher in the Earth’s atmosphere, the rat)-vuy; vgahgk )fa s3( eivt*(io of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minin5m1amef: 5ibmum speed an object must have to bna 551i ef:mmleave 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. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at room temperatulijvrzmm 0ep7z rf7,691j;; nw0wioy re. What can you infer about the molecular properties of onzi0r0ljmw 9izofj 16;;v7 mne,ry 7pwe relative to the other?

Explain why a hot humid day is far more uncomfortable than a h x*fqdvbqu.t/: w0m;; cpsxvm3:nv )x ot dry day at the sdv3q: xmwvcsx:p.; v;qnf/ t *bumx)0ame temperature.

Is it possible to boil water at roj/ of5ua*ut0 wom temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the humidity a4hfi-) : d(i/sgj9bgbb oy2ais different. Which isfgb9a/ h(oajg-bbsd)4:yii 2 more dense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap of an overheated a/cy zg7pgh4 urf 6/+u jld:kpo.pbd.0utomobile engine pkp7 .4ly: /u+h.df/p6uggcoz0j bd r.

Why does exhaled air bdacgv fvxi0 psj*84/s u) hb- x;/6raappear as a little white cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gv* 2 fe7-wpl0r8gsgn nram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring k* k2zpk+b4gkcompare to the number in a silver ring of 4g2+kkz*k pkb the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this on th+cwyl(4wl9s l t*bc 5he Celsius scale? c(45sw *yh+btc wl9ll   $^{\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 recox8z d4ra8,i9wdj (hcxduy 4a 3rded are 136 $^{\circ} $F in the Libyan desert and -129 $^{\circ} $F in Antarctica. What are these temperatures on the Celsius scale?high =    $^{\circ} $ C
low =    $^{\circ} $ C

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

  In an alcohol-in-glass thermometer, the alcohol column has length 11.82xlpzs1+kc: +j cm at 0.0+ :ls+jkc1pz x $^{\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 w:ohqt x-lk;h+5m.*jgn nov /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–ufgl) n*ble:pab 3*(: kw )lbr29) is built of wrought iron approximately 300 m tall. f u)er*(nlabb* gl kw3lp:)b:Estimate how much its height changes between July (average 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 than28spz6o4 sn yb the rivet hole are often used and the rivet is cooled (usually in dry ice) before it is placed in the ho6 2pnsysz o8b4le. 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 waterm6ziyap,w xw9q3*4wy.s qr d 2 at 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 ihhxz* ;ud fy,yd(n(xtu9i;5ds; q8man diameter. What will be its change in volume if it is heated from 3auzd;*d;h5xmyq 8;i(fh 9s,un (dxt y0 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass istd.b8 yp;h 7a (8ctsxi:no-uk filled to 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 55.5rwha 97,9mlc u*-qyco 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 placed in a ring madwi(51 o 4olxfv44bqcge of iron. At 20 $^{\circ} $ C, the diameter of the plug is 8.753 cm and that of the inside of the ring is 8.743 cm. They must both be brought to what common temperature in order to fit?    $^{\circ} $ C
(b) What if the plug were iron and the ring brass?    $^{\circ} $ C

If a fluid is contained in a long, narrow vessel so it can expand in ess y p8ux*: m1xdp8ap e5s3rrvo+entially one direction only, show that the effective coefficient of x*p 1v:pprmeos85+ d ya8ux3rlinear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the db:ee 51-izd* iznnfb f)m *k3gensity $\rho$ 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 f8fef (fs9fwwcj*q6e* 1rx* aof length l and width w has coefficient of linear exps816f a*f w(fw9*fr *qfjexce ansion $\alpha$ 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 isotropifq g my y,sn 63pt,p.ksy65rv6c 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 i5tih76;fq dh ms made of brass and keeps perfect time at 17 56t ;qi 7dhhfm$^{\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 :+wn ty qyae;2diameter of 0.140 mm. The bulb has a volume of:an+2eyqw ;y t 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 0.41 m i1vu90( ypi)5s; q atmwyta48t nwb,rcn( 2dc ks rotating about its axle on fricsiu,8v4bk )ap c ( nc mrd5ty2t(twa91yq ;0nwtionless 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. How much stress is req 0t; :qn5anvzguired to keep it at this le t;avqn n0zg:5ngth if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal stel20b5slxx zx7el I-beam of cross-sectional area 0.041$m^2$ is rigidly connected to two vertical steel girders. If the beam was installed when the temperature was 30$^{\circ} $ C, what stress is developed in the beam when the temperature drops to -30 $^{\circ} $ C (b) Is the ultimate strength of the steel exceeded? (c) What stress is developed if the beam is concrete and has a cross-sectional area of 0.13$m^2$ Will it fracture?

  A barrel of diameter 13x7l3npi )rxlg n.hl82e- nya74.122 cm at 20$^{\circ} $ C is to be enclosed by an iron band. The circular band has an inside diameter of 134.110 cm at 20$^{\circ} $ C. It is 7.4 cm wide and 0.65 cm thick.
(a) To what temperature must the band be heated so that it will fit over the barrel? $\approx$   $^{\circ} $ C(Round to the nearest integer)
(b) What will be the tension in the band when it cools to 20$^{\circ} $ C?    N

  What are the following temperatures on the Kel3 ;:/btlttrpb* mhc bv (a(ul6vin 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 temperrz*p9pd4t )q,w bv;m gature on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun are o-i*9 - ezxenbabout 4000$^{\circ} $ C and $ \times10^{6 }$ $^{\circ} $ C respectively.
(a) What are these temperatures in kelvins?    K    $ \times10^{ 6}$K
(b) What percent error is made in each case if a person forgets to change $^{\circ} $ C to K? $\approx$    %(Round to the nearest integer) $\approx$    %(Round to three decimal places)

  If 3 $m^2$ of a gas initially at STP is placed under a pressure of 3.20 atm, the temperature of the gas rises to 38.0$^{\circ} $ C. What is the volume?    $m^3$

  In an internal combustion engine, air at atmospheric presbep* meu1 8 anezh*y57(tl5mmsure and a temperature of about epy8 men(a 1*z *l5mumht57 be20$^{\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 ga gf892-3yaqh71qedsbj f hii vw k;(v:s law.    kg/$m^3$

  A storage tank contains 21.6 kg of niy cf wqoez3,i8j- m*er:,qx, ptrogen ($N_2$) 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 ST(s4dwpb9;ddyn,: xy ix7o vg3P contains 18.5 kg of nitrogen ($N_2$)
(a) What is the volume of the tank? $\approx$   $m^3$(“Round to one decimal places)
(b) What is the pressure if an additional 15.0 kg of nitrogen is added without changing the temperature?    $ \times10^{5 }$Pa    atm

  If 18.75 mol of heliumz9e a0vz xc9o(m6ec7v gas 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 holding 105.0 aon.87kzwbz7q m0/fs fo 5(nb kg of argon gas at /bw(kmaqb7z7 zn50f.oosfn 8 385 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg of 9fwc:e n3,kyq8s1/q i6y dvc f$O_2$ 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 the2e07sfqanqj hy*p 8/x balloon, which makes it less d/7a qhjqyfpe 2ns0x8*ense 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 ax6d ((5ajohsaw/8sh;x y2kw*-b g gwair 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 1 *boenfw(2ff z(3nq *olj+fr/8.0 $^{\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 kb 2 : 14yurtj+bpgyr5at 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 5s4qm1e-un3)hb k(f zq dmli v.ey8v9molecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L?x9v h wx-bp /v 6vl*ox/gaq m*qa,8w*m How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) mo*v l8n b i3*,0yfpe93u;ao wcbea izs;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+-c6qf /1fjnt f*lk+x -vgv 5fnk:ycs 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 he )utj fs nydhhn (;p6pk)n8 5-9(cxmbreath you inhale that were (6 8jh)ny;(ef hk-t )cp5 dxmpuhsn9n also in the last breath Galileo took. [Hint: Assume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational 0y nvb8d9 +njsp1t3 gbkinetic energy of an oxygen molecule at STPynbn j1dstv0 b89+p3 g?    $ \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 su*fbvrgfmt3v(*syn pt98 ;;m +z/elu nrface of the Sun at a temperature of about 60tbg*vn+ ft;uze v9n8ps f;m3(* /mlry00 K.    m/s

  By what factor will the rms speed of gas molecules increase if m 2z *p4ohk2jothe temperature is increased h4*kj2o zo2pmfrom 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,sw c+uj15bejrvnn: 4 r6/c, zj 6, 0, 4, 1, 8, 5, 3,c r:jjw ns rbnc5 ,/6+4v1ejzu 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas atkwi1o, syv 2il9* i-1m8jdynj 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 4p),npumua21j3zj cjdoubled while its volume is held constant, by what faz1 c4,uja)pp2 u3m njjctor does $v_{rms}$ change?   

Show that the rms speed of moleculeyjg8vbt89 3 q57z+daifr s (dowjml5 +s in a gas is given by $v_{rms}$ = $\sqrt{3P\\rho}$ where P is the pressure in the gas, and $\rho$ is the gas density.

Show that for a mixture of two gxt5z qqz7 j4nf8jp7l/+1hf bm yi,x;nases at the same temperature, the ratio of their rms speeds is equal to the inverse ratio7 n;qix75fj+1p z48m/hjl,zybn xtq f of the square roots of their molecular masses.

  What is the rms speed of nitrorilg1s e:f+m922 j zsggen 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 1:b( 9rjm lwjean 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 betwfio9*n h9m*ig:dj uc:een nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms o,t7/rik z0zq8ixy1 kspeed of an amino acid whose molecular mass is 89 u in a living 71yzoiz/tr kxk,0qi 8cell 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 gaonnd,5in1 qt 4lh +k6bs 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 uraniuz :d(, k-lf 0gw6s(brvk28 pu.slkjzxm, $^{235}$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 p5lvg +d8b8v gjhases 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 the tez qk(0/s gasw0mperature is (a) 0swzk(s/0 gqa90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity is 50% on e sa9ed3qb gh9l,3 o8sa day when the temperature is 25e93 q9boeg,dl3h sa8s $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water boils atlbo;7)v:opwuwzk +.q 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is 0.72 atm, estimate7b wbuasy xq82mg*h. 9 the t qax8hg .y*wu7mb9 b2semperature at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day whet7lqns)m a0u *n the partial pressure of water is 530 Pa and the relative humida)s*tunml0q 7 ity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the temperature is xw8 6i7mbn(y y25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure in (bpyfo0. 3igdside a pressure cooker if the water is boiling at abyi 0p3.f gd(o temperature of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in aafs6u(l( k00uvut0.myb q/jc4 rld)y 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 dewl ,.an 4n emcy:27nie; 5mnbr c.x5edv point 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 forhyo+ r. jk nn7:b9; 4mdt2ojdz a glycine molecule (see Table 13–4) to diffuse a distance of:nth ddoyj;r2+ oz7bj49 k.nm 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 *y 62yvfwji a*to the interior through tiny tubes called tracheae. An average trachea is ab2**iwy6 ja vfyout 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 has been c8rp;lax 0dbd7b0k5 hpalibrated 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 caliba,g/mj tt1xt*m y(le- rated 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 temperatu)ni 7f+c51tc de t5njlre. How much error will be made in a recipe calling for 300 mL of cool wate5+ c1j)nnifc te7l5dt r, 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 cylinder is initially 28 atm. Afis ;1 0x5 l3to0vizkuiqp q:5zter many balloon0ii3 ukpzz5itoq5v0 :;sq xl1s 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 ozt5xm:lr0c/,dt6fi 2 xnj w ;df air molecules in a room of length 6.5 m, width 3.1 m, and height 2.5 m. Assume ;5tf02 ,t6 xcdw:j mlix nr/dzthe temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of ma;pez8ek +j 3xxtter 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 attainable using the best available xc sh:no9ktch-8 oyyba:;0 ;fvacuum techniques is about 9t -hc;;hfa8o onkxc yy0s:b:$10^{-12} N/m^2$ 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 lung(s+ jdiodfitqn4;np ).v / xt,s to full capacity of 5.5 L when 10 m below the surface, to what volume would his lungs expand if hpifjn v+q(;.i st ,4dd)to/ nxe quickly rose to the surface? Is this advisable?    L

  A space vehicle returning fr.fk- o+ vur6ta* as/v *iu7hbzom 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 of special materials; indeed, pa*/- v. tk7+uvz*irubo f6haasrt of it does vaporize, and this is seen as a bright blaze upon reentry.)    K

  The temperature of an idecabfjtj :ues,1*+t :p5(laf-vp ;nrpal gas is increased from 110$^{\circ} $C to 360$^{\circ} $C while the volume and the number of moles stay constant. By what factor does the pressure change? By what factor does $v_{rms}$ change?$\frac{P_2}{P_1}$ =    $\frac{(v_{rms})_2}{(v_{rms})_1}$ =   

  A house has a volume of yh eb. +z3,fwi770m$^2$ (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 surf9r4i 2maxs9hsc6e 4v oace of the Earth, estimate the total number of air molecrao4v9 4s xc9im2 seh6ules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molee fiunqgjja 41,1yq+ *cules 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 uskdv3j*,3l) tj sf/ub r 2t.8l hrs*nxred 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 presj) 8ntlfu *j*,kbd3x/rsr tsv32. lrh sure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a box. * t p:pobuci23r8bfwl 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 h;k ea0pyx ;s0p-9lal:u 4mlb 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 f2qt4umj6xs /68erxz bit 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 tizum.ycr+c,yo t 64p9oghtly onto 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 standqo56fjwakeie)69 l5us 0wj ob r(0c 9mard, 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 pressure of 195j *i 4bd u:0uxtk.+fl3m*lbm a 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 from7 y9lnm;xc aikk z9do sg)l5,; the Earth is $ 1.12\times10^{4 } m/s$ so a gas molecule travelling away from Earth near the outer boundary of the Earth’s atmosphere would, at this speed, be able to escape from the Earth’s gravitational field. At what temperature is the average speed of
(a) oxygen molecules,    $ \times10^{5 }$K
(b) helium atoms equal to $ 1.12\times10^{4 } m/s$    $ \times10^{4}$K
(c) Can you see why our atmosphere contains oxygen but not helium?

  A 1.0-kg trash-can lid is suspended against gravityqqie nd6 i:utnx1)2a8 by tennis balls thrown vertically upward at it. How many tennis balls per second mui1tq):d6nu q8anx 2ie st rebound from the lid elastically, assuming they have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a n92w aw sf9w 9sunl.+q3.00-cm-diameter (spherical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature i u99n fsws+.al2n 9wwqs 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 air on the foda; uaxx-* 7 7abcr6sxllowing two days: x a*bxxa7 -6;sur 7dac
(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 ipfl21/w*ubyylap + f-ron at STP, and when it is a solid dyuawfy-p/b+2p f *1l leep 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 gaz t541rho6aa as at constant pressure, the coefficient of volume ex61at 5rha4oa zpansion 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 thee sl py:8da+4a ieackybi8.6(ir cellars to prevent rot and 48dlcpsk6 e8 a+.yiya aei(b:mildew. If the 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