Which has more atoms: 1 kg of iron or 1 kg of aluminum? Seeyml- h*zc3e orj1 12vl the periodic table or Appendix jlohylrm-32* c1z e1 vB.

Name several properties ojryoln k84 00a( xp0kwf materials that could be exploited to make a thermometerl y04 rakjn0owxpk80( .

Which is larger, 1 C ;s bohmq u pf.sn+r+./0zu2sv $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B is not in therkg)3yz c 0pju/mal equilibrium with system C, what can yzk gpycuj03 /)ou say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to a strip o, v: cfevg-tg8 hi.tg*f iron. When heated, the strip will bend. Which metal will be on the outside of the eg *ig:-8v vg.cfhtt, 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 lqx 4kxc1ky8btl3 ,r0qinear expansion $\alpha$ are $(C?)^{-1}$ and there is no mention of a length unit such as meters. Would the expansion coefficient change if we used feet or millimeters instead of meters? Explain.

Figure 13–27 shows a diagram of a simple thermostat use mbiakpj4- y;yr2.v r:,vgh.cd to control a furnace (ocyy-rh;j 4.ikpv.,mav2: g brr other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch is a glass vessel containing liquid mercury that conducts electricity when it can flow to touch both contact wires. Explain how this device controls the furnace and how it can be set at different temperatures.

Long steam pipes that are fixed at the ends often have eme 7+2ku/g,kso-wns a section in the shape of a U. Wh,/koe +2-us7nsgwke my?

A flat, uniform cylinder of lead floats8grnr jo0/-xv 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 t)0d0 rgj,qooc +w4ers4cs rj1 ub of water, the mercury initially40g0 4wrj,1cors)s+c jderqo descends a bit and then rises. Explain.

A glass container may ff ,vg:1aji:ubreak if one part of it is heated or cooled more rapidly than adjacent parts. Explainfvfj,1i:gau : .

The principal virtue of Pyrex glass is that its coefficient of linear expro)n.f:ypke9f ut/ i 8ansion is much smaller than that for ordinary glass (Table 13–1)fu)tipref /y .8k: o9n. Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurate at 20 l.l2s 36in+mn kh. ysc$^{\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 ws0 jp5rdt)h;cill cause its bottom and top to bulge so badly the can will not stand up. What has hahd;5 psjt)rc0 ppened?

When a gas is rapidly compressed (say, by push2oi-kvf j/zwva2k :i5; hf;eq ing down a piston), its temperature increases. When a gas expands against a piston, it cools. Explain thes j52/wv;2 akff hivo;:eik zq-e 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 alumc7htf g (yq0;zinum sphere submerged in water increase or decrea0 yhtq;f7z(gc se if the temperature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follor*s ivj0qu* f nnhjsjha962;(ws from kinetic theory and the relation between average kinetic energy andvn n9j6ijs*sj qfh; 0h2*(ura the absolute temperature.

Explain in words how Gay-Lussac’s law 54e iz8 i+fya1 4j*6ykvbjisodakmkx; g)i:)follows from kinetic theory.

As you go higher in the Earth’s atmosphere, theszsvu7z20p+e6bnoh :. w5af)u yj1kg ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed+dbfmm jk,qys),. 5f xnvi,bfsc98u0 an object must have to leave the Earth and never return. The escape velocity for the Moon is about one-fifth what it is for the Earth due to the Moon’s smaller mass. Explain why the Moon has practically no atmf.5sb+n8vm0u,by,k9m ff siqj, x c d)osphere.

Alcohol evaporates more quickly than water at room tempera9vlq3 lqb1jeaz6.s* ature. What can you infer about the molecular properties of one relative to the other?a.*e q61l9b vzlsa jq3

Explain why a hot humid day is far more uncomfortabm-jcvig+x:l 22; t+ zmthd 5jhle than a hot dry day at the same temperatur:xm++v;icjth j md-h2tz lg25e.

Is it possible to boil water at room tempegiay;3b kp 0 ;9qm6;a iobshb9rature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the humi fiu y+ g2mj1ja(;q0apdity is different. Which is more dense, the dry air or the humid aig ;am+a2juj( py10f iqr at the same T? Explain.

Explain why it is dangerous to open the radiator 7b19fg8 aq igs tn6p:jcap of an overheated automobile engi:1b6gs8 f naj i7gqpt9ne.

Why does exhaled air appear as a little white cloud in the wintew*h mf 6wvob0/r (Fig. 13–28)?

  How many atoms are thereb+ciy .ajyjle61/58 t 6 fydmm in a 3.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms inr;4.ph 1gf6h edzk2jd a 26.5-gram gold ring compare to the number in a silver ring of the same mass? fpddgh. h2; ze1kjr46$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this on the Celsiusjr6 j uuqq)/;w+e nqlla9w p;7 scale?9qqw nlq+;;a) w6u7r/epjlu j   $^{\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 rt:4dib, yeo* 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 k(y658r f gc lhtis6(qcolumn has length 11.82 cm at 0.0 h6slqif (6kcg5 (r yt8$^{\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 (2+2qo6ng6smj - ag g4bt0 $^{\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 w zmg(er2w ,;gs3fh.rd rought iron approximately 300 m tall. f zem;s( wg r.r2h3dg,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 than the rivet hole are often used hl8 r-id l,bpn5,y ns 83)iatxand 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 hol 8ny bina)plt 8-is,5,r3xdh le 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 at 4ks j. :wpaj,e. $^{\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 s*u3 0di4u7 hb4 jftil5bet6lbu. gw3in volume if it is74 e6lb .wht *ul0d3g 3j4iu5utfi bsb heated from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is fille b yqjgulsa;7l+k1i: 1d 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 55.50 mL of water 1u d4jdhbni,3 flw0x.wrq0r+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 9)j+ vllvrs 7niron. 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, narrowz0.8se7unxa8dqf ou. vessel so it can expand in essentially one direction only, show that the effective coefficient ofs0z.une8 qx.7 dauo8f linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the chilf8(i.ri8 .ulwo ;zaange in the 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 h,6)irkb zt/i gas coefficient of linear expansio 6k,tg rb)zii/n $\alpha$ 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 isotwapcd (; bgi:+2fcw/z ropic 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 grandfathc0taq 2fw (k, h(jv)sw.6hbyxer clock is made of brass and keeps perfect time at 17 )k0,6stqawh(jc hb . f(vw 2xy$^{\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 kogbl xxg /)d7 7p 3jhj5fv2v2has an inside diameter of 0.140 mm. The bulb has a volume of 0jfx ho37x7d2)vb gjpl52gk / v.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 froa bii78n 4-o -e gz3h*u9ddof radius 0.41 m is rotating about its axle on frictionless bearings with angular ve-frd 4i73u*nhga - boi8 de9ozlocity $\omega$ = 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 requirqnwv8 zw1+zxsv 60h8p ed to keep it at this length if the temperature increases to8w 6 zvh8np+ z10wqvsx 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal stee.tmtxc*: g5r fl 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 +efke9h ohb.se71 x +s134.122 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 v7o+d ge6u s4 5:y*koiftf. wrKelvin 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 Fahrenheit58php. gkvw v/ scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun are about 400yu 3a;4 fxt.3jsvjsrk h5+e+g 0$^{\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, ag,e;dp ykl 9-lir at atmospheric pressure and a temperature of a9kyd el p-;g,lbout 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 ;pl0 6eev zy1sideal gas law.    kg/$m^3$

  A storage tank containg-4yzvi;oo p.qf.lf 6s 21.6 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 contains ;.xvuqqe(wo *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 gad4s n4e+ *q/j- b:8xqispkqm os 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 cte888d7lv3jvgx/eqs 2 vnj5hontainer holding 105.0 kg of argon gas at 385v88en3e7h 2 sqx8vtlj j d5gv/ K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kb hx//xu )a6k 49gn ,c+xni p: 8wyf)-ilvmeefg 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 heating the air inside the b 56j u zjoews*zyle w(4 -6xa8mcrit;(alloon, which makes it less dense than the air outside. Suppzlw 8mwac zus-ee ;(x6ij(ty5j o4 6*rose 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 1.c5t7w1 h tokz4bh1au*:m bom5 $^{\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 p pqxubdve2f9b)6 j3i77zt4y18.0 $^{\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 chil l0 vesja3 hrp(()2c xyv9kb0jd’s hand at sea level and 20.0 $^{\circ} $ C. When it reaches an altitude of 3000 m, where the temperature is 5.0 $^{\circ} $ C and the pressure is only 0.70 atm, how will its volume compare to that at sea level?    times the original volume

  Calculate the number of molesh8qf92;qm) 1n 3xvyukj: skh cules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How many molecules?*vwi7hi m;wpek rv0rl)* 6t6g    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) :4mq0b9t:qk ( rtge:lxg1vl :f-brbf)tr-samoles,    $ \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 01 h0uasrya;n5.1$ \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 inha;(d ;3zz ikrmqle that were also in the last breath Galileo took. [Hint: Assume thek m(dz;q;irz3 atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinest*te- h61m pxtic energy of an oxygen molecule at ST-p *et s6mxt1hP?    $ \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 atoh5(vith*p4 y0ycdrb3h)axc 5 ms near the surface of the Sun at a temperatura)t( b5d4h chvyxpry hc03 i5*e of about 6000 K.    m/s

  By what factor will the rms speed of gas moleu4o myjz2t0*wpc1k iq.3sa-x *snm e0cules increase if the temperature is increased 40 ta e.0ck umx*ps3yi2no qmzw 1s-*jfrom 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: mgk)nh+4 +pgo 6, 2, 4, 6, 0, km+g)p4 onhg+ 4, 1, 8, 5, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at 20.0 5ub sk*to.fmyd,43 mc$^{\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 doub+ho 9qds, r-gpled while its volume is held constant, by what fac,g h+r oqdp9s-tor does $v_{rms}$ change?   

Show that the rms speed of molc,g-t /ssrx4r ecules in a gas is given by $v_{rms}$ = $\sqrt{3P\\rho}$ where P is the pressure in the gas, and $\rho$ is the gas density.

Show that for a mixture of two gases at the same temperaturb.g82d e( i b9wk))7.jsre,q vo opnqze, the ratio of their rms speeds is equal to th2 g zpidsjn78q, )).kb(v9b q o.eerowe inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen mol) wxb hccq th- b:s052dty5b4wecules 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 agc *0rk pl,f,u qwi1vs*;jv+ speed of 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 between nitrogen molecuzffjsfot s3,d-(b*b : ,b4yz8oaq ch 6les at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms spe fkpft5pyh3t;kk7b5,fci g .*ed of an amino acid whose molecular mass is 89 u in a livi7ky35fh5 kcgfp;tp ,.fk* tibng cell at 37 $^{\circ} $ C.    m/s
(b) What would be the rms speed of a protein of molecular mass 50,000 u at 37 $^{\circ} $ C?    m/s

Show that the pressure P of a gas can beqy)1. xtm.83uqm b,8fgwtet d 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 ur:n, kcik-mqhkjma.fu ,m(nmrb 6 a fy4i*b.-1anium, $^{235}$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 whatto* -g2oc4lt b phases can $CO_2$ exist? (b) For what range of pressures and temperatures can $CO_2$ be a liquid? Refer to Fig. 13–21.

Water is in which phase when the pr18vwg -ur6j0jhy ba1-x3aa mpessure is 0.01 atm and the temperature is (a) 90a-aa-10hjpvmjyurb x6 w3 1g 8 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity is 50% on a day wvq.ks+f fd*v m*qxj/(ly o i*vv :,jk3hen the t(f /k,i dvmf*os. vkqy3vljv:+ * *qjxemperature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water boils atzxr0rs * f)s8c 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular plac7ax6y,y+n df ke in the mountains is 0.72 atm, estimate x, dn7fk6+ay ythe temperature at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of . phcj,mof t57z r(k 9xfjdu1(water is 530 Pa and the relative humidipxj 7,1fjcu r .9zk5thdmo( f(ty is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial prenm0wgwj 0zt6)n h:8 cmssure of water on a day when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressum4m u5z*gd.vd p07 o-vei8qzgre inside a pressure cooker if the water is boiling at a temperaturvpo8g. z 70 dgqeid5v* umm-z4e of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a uzh9/ rj ,; - hawm2zki jggv;;ni54asroom 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 po k +)j fofoj ot*lx.zl(gph7(.int 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 molec yh ylus1 jr46yggpn/ud 4yui7.u25)z ule (see Table 13–4) to diffuse a distance1l yu72ny5)g. u4 4rpsyi6jgyduz /uh 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 gxxu3tpdam k/in-n e7:8- a s2insects to the interior through tiny tubes called tracheae. An average7tgdun:k3-xasna 8-/ ex pim2 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 has b(y+dbd8-anh2s:)e 9zv qzmckeen 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 b c8kj* bp(hz m59)e9e;r2(riquiyxmaeen 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 fk 3,.gex 8;hwdb+k:zv/wlt nat normal room temperature. How much error will be made in a recipe calling for 300 mL of cool water, if the water a3n.e +lkg,z8xvfbd wwkt h;:/nd the cup are hot, at 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in0zn ;z0; blljfm-8 v9 favt4ig a helium gas cylinder is initially 28 atm. After many balloons have been blown up, the gauge pressure has decreased t 8al0v fzv90glmbt zn-;;4ij fo 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air molecules in a room of length 6.5 m, width 5qw.k t8*u5eb1mh0( x bsc ovw3.1 m, and height 2.5 m. Assume the temperatw5s * 1 mc.w8q xhb(vktuo0e5bure is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of maf(a- .r9k257 ub- ppybjvtznqtter 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 ouf/4 pt)m c7dhf oj hi4:7t2ravailable vacuum techniques is about /p iuc4d:7jm 7t2)4rho fftho $10^{-12} N/m^2$ At such a pressure, how many molecules are there per $cm^3$ at 0$^{\circ} $C?    $\frac{molecules}{cm^3}$

  If a scuba diver fills his lungs to full capacity of 5.5 j oi,a(yv )lc:L when 10 m below the surface, to what volume would iyc)a v:o, l(jhis lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’zc+n qzflr9fy; ;( vqo,/bv,a 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 wqvc(a r;n+, fvyf;o b,z9/lqz hat temperature? (Because of this high temperature, the nose of a space vehicle must be made of special materials; indeed, part of it does vaporize, and this is seen as a bright blaze upon reentry.)    K

  The temperature of an ideal gas is increased from(gnm(n6r2yz7 d:lkrg w -o2rn4wokn4 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 770m5 mpn; k2.s9(7 vfi9n kprd9wp6br nst$^2$ (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 surfacev5d: k2,d2 iqn8cwate of the Earth, estimate the total number cidv k5 en,2a28td qw:of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecud0h,p uarq;ob6z5io 6les 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 q: yf4seyiwf 0ih66)wof oxygen used 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, measures06w:f)6qe4 hywfyi i d at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bojhi9s kws24a *wl 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 gasolinl d2bb )b2.xbr z)i* v+pe5vkte at 0$^{\circ} $C is 0.68$ \times10^{3 }kg/m^3$ What is the density on a hot day, when the temperature is 38$^{\circ} $C?    kg/$m^3$
What is the percentage change?    %

  If a steel band were to fit snugly ae69m9 cp7osk mround 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 o -x1*ccxq,vzfnto 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, adoptwe yodor;7n sj39ue*0y8y(q 2gqc (xned 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 u: sb6sb9immkh;, jr,charged, has a pressure of 195 atm at 20$^{\circ} $C. The volume of the tank is 11.3 L.
(a) What would the volume of the air be at 1.00 atm and at the same temperature?    L
(b) Before entering the water, a person consumes 2.0 L of air in each breath, and breathes 12 times a minute. At this rate, how long would the tank last?    min
(c) At a depth of 20.0 m of sea water and temperature of 10$^{\circ} $C, how long would the same tank last assuming the breathing rate does not change?    min

  The escape speed from 5px 6*,muq jgwthe 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 l/nj hw-vovn: q1qr1bdt/h;lm(c)m:tid is suspended against gravity by tennis balls thrown vertically upward at it. How many tennis balls per second must rebo/ btwv;n h/1hqot:-cd q(nm rv)mlj1:und from the lid elastically, assuming they have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameterera2(, ykb+gp (spherical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the air b,ykgr2(eb +a pehaves 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 followi cf8xay7+)j*iz nq2 07wfxngdng two days: agi 08* fdjqx 7cxnfz)yn +27w
(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 dxdw o;oyl ; 0:9i;r reg7twum(ensity of iron at STP, and when it is a solid deep in the Earth where the temperature is 29 rwegi7rdx:ow;y; ;(mul0to000$^{\circ} $C and under 5000 atm of pressure. Assume the bulk modulus (90$\times 10^9N/m^2$) and the coefficient of volume expansion do not vary with temperature and are the same as at STP.    %  ----待选择----decreaseincrease 

(a) Use the ideal gas law to show that, for an ideal gas at constant pressuuo el+l w:ewo(zy k+z)c+:4sure, the coefficient of volume expansion wo)+ w+4 :lus: e (+leoyzkuczis 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 dehumid e-rr;q da+;swify their cellars to prevent rot and mildew. If +w-qrda ;s;e rthe 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