Which has more atoms: 1 kg of iron okcbn boz+g jq59448 eyr 1 kg of aluminum? See the periodic table orq 495+nzjbk eo y8cb4g Appendix B.

Name several properties of materials tu6y*tl(p vr5ohat could be exploited to make a thermometer.r( *oy u6p5vlt

Which is larger, 1 C lnuv177e19 adq 4yoel tkd,w9 u5u8 io$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B is si ug):)-x0 qxjn q4otdt lmu+/fjr+(not in thermal equilibrium with system C, what can you say about the temperature)m u:0+lg(ts/dj toxxrq -)i4uq+jf ns of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to a strip of iron. When e1m (q ajf*zz-heated, the stri( q *jafmze1z-p will 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 coefficient-4,oddhujnj2q+ j pgxb2-q(r of linear expansion $\alpha$ are $(C?)^{-1}$ and there is no mention of a length unit such as meters. Would the expansion coefficient change if we used feet or millimeters instead of meters? Explain.

Figure 13–27 shows a diagram of a simple thermostat used to control a f*rf at o63(cua:0ip dzurnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch is a glass vessel containing liquid d0 3or*z 6tafpuia c:(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 tox5 q9z,bja 0whe ends often have a section in the shape of a U. Whoj a50z,qb9wxy?

A flat, uniform cylinder of lead floats in muj7)x u.o 3z be*;pcsup e3(ciercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass t +zf a7j:gebx.yrie(, hermometer is first placed in a hot tub of water, the mercury inity j. ,r+za:ixfge 7be(ially descends a bit and then rises. Explain.

A glass container may break if one part of it is heu3ahjvf7a-s ;ated or cooled more rapidly than adjacent parts. Ex3va fhs7u-; japlain.

The principal virtue of Pyrex glass is that its coefficient of linear expansio r7 i.z9jiv*zbn is much smaller than that for ordinary glass (Table 13–.z9iivrz*7j b1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, ayz;zbmp2j1t0 ccurate 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 bulge so badly rh:q:akrc d* a2r 3ad;the can will not stand up. Whatc:: arrr3dqk dah2a* ; has happened?

When a gas is rapidly compressed (say, by pushing down a pistrdiw4c y mum2 p;iux:lz5v83 )on), 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 strike the moving pistonvw5pxi l :ir4u8ym2zc;d )u3m .

Will the buoyant force on an aluminum sphere submerged in water incrill4 /ng eh1khno (855ukfn :rease or decrease if the temperature 1n4 (8nokhu illgrn5/ fe :k5his increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Cha a2e/ o9ylhkpvy62f7nrles’s law follows from kinetic theory and the relation between average kin2ae/ yhp9 vflo yn67k2etic energy and the absolute temperature.

Explain in words how Gay-Lussac’s la m .3xqgij4w7 a.dhdx2w follows from kinetic theory.

As you go higher in the Earth’s atm4j/ r4 5v/t/gcmequ-ja rksk+osphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed an object muslzu:og0 w9o9 et have to leave the Earth and neve9:ozl9eug o0wr 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 qrm 99li68g s ms13o kg4jg5q)d4uswpouickly than water at room temperature. What can you infer about the molecular pmg5u gsi9 m8jgs)o39pod q4w lks4r16roperties of one relative to the other?

Explain why a hot humid day is far more uncomfo enr/+ , zna iq-efpnd.i8p3e(rtable than a hot dry day at the dp+ nip.,z3i(ea-e8r/nfqne same temperature.

Is it possible to boil water at rooect u(cmn a1,,m temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the sal, cm5d)m5od4hmf9md me but the humidity is different. Which is more dense, the dry air orm4m hmo) l9cd5,5d fmd the humid air at the same T? Explain.

Explain why it is dangerous to open the radc9h ;a7ou1ctjiator cap of an overheated automobile engine.ch9 t j;au7oc1

Why does exhaled air appear as a little white cloud in the winter +8.en7arau5,m amb:t l. mang (Fig. 13–28)?

  How many atoms are there in a 3.4-gram copp5izty-ye5k9w t x xc/7er penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare to the yll ddfqo)r+8j e0dzq.2p)f9o s cu8+ number in a silver ring of the sul y 0.9eo ))l8r8+f ddfdzq c+opqjs2ame mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. W/e9 vq,e :p ex/(a3djwtb- ;nznohy v7hat is this on the Celsius scale?vex9:otzvnp b/ ay;/e(w 7hen,-q3jd   $^{\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 lowes n5br vq,jm6j/dp vsfs: 9ck)4dt5q,at 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 alcohol6cug t0l 0(8)pxzntj t column has length 11.82 cm at 0.0 )nx(t0jlp6t t 8uzcg0 $^{\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 1khg - ol7a4l-y2 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 approxxb2bej+)b+cp p-z2 msimately 300 m tall. Estimate how mu-xbzmjbep s2 )b2pc++ch 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 ofte qbh4,v4c5yxm :ih hz1n used and the riveyc4hh45m 1,:qhxiz vb t is cooled (usually in dry ice) before it is placed in the hole. A steel rivet 1.871 cm in diameter is to be placed in a hole 1.869 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 447pd v9v k.dtv $^{\circ} $ C is $ 1\times10^{3 }kg/m^3$ What is water’s density at 94 $^{\circ} $ C?    kg/$m^3$

  A quartz sphere is 8.75 cm in diameter. What will be its change in volumejp *;g, rmdnttnm7 kytb3nz6.na-65 v if it is heated f 3yn *,ntk6m gd-v5 ztj6.tapr7 nbn;mrom 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the br)2*hjmmy 7hc on1.n73c;wkj(j:qug gel l k)vim 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 wate,;uvx gm s;0 1kbqbh-obfqq mq,,d ;c4r 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 stu e c1:h*c,gbe placed in a ring made of iron. At 20 $^{\circ} $ C, the diameter of the plug is 8.753 cm and that of the inside of the ring is 8.743 cm. They must both be brought to what common temperature in order to fit?    $^{\circ} $ C
(b) What if the plug were iron and the ring brass?    $^{\circ} $ C

If a fluid is contained in a long, narrow vesqtdyc ) re4*(2tq8idsop6h 3wsel so it can expand in essentially one direction only, show that the effect6sr23y* t4h8 d(cqdip) etowq ive coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the z3awq52fw7w m*l. lr15kihqk 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 widthefz-:;foxpv t6 a:2x id 8/o qk7xr)qq w has coefficient of linear expan8r;)x6fi:x: qe pdvqoztf/ a k-7o2xq sion $\alpha$ 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 isotrop4wh4zx+(bt0e fc8r dd ic 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 made oqguu +9y to w ns7gz/l;p1x5u72n,hnsf brass and keeps perfect time at 1/ugn ,2l y;t5+7g19hss unxuq7 zonwp7 $^{\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 thermo 8xmx,:zif 9 b pd,xhg9p3nw*dmeter has an inside diameter of 0.140 mm. The bulb mxp: 9 p *wx8g,9hdb,inx3df zhas a volume of 0.255 $cm^3$ How far will the thread of mercury move when the temperature changes from 11.5 $^{\circ} $ C to 33.0 $^{\circ} $ C? Take into account expansion of the Pyrex glass.    cm(b) Determine a formula for the length of the mercury column in terms of relevant variables. Ignore tube volume compared to bulb volume.

  A 23.4-kg solid aluminu 1 ;x82sqlyyhlm cylindrical wheel of radius 0.41 m is rotating about its axle on frictionlessyy2xqls l18h ; 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 requiredi5kc 0 xy6w/xvc.dmm4 wkyc.0xcdi4 6/m5vxm to keep it at this length if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-sectional au0t: cxz2qv7:/: * ouepvve ltrea 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*l7t,nor;x (hoz7 trr.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 Kelvi7 pjj9/;k4exw)t o 3 j0v v0jfouf4ajzn 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 5mp4hwg( 4 ,k svq+ertthe Fahrenheit scale?    $^{\circ} $ F

  Typical temperatureshhnrrj )9j+7 u4gn. k,ha2vq9lxf rt4 in the 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, air at atmoq0 sej*ka1vkk7e0r 0 bspheric pressure and a temperature of about 200kj7qr1ae0 v 0*kkebs $^{\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 us)c/ng 9 ig tfmk)w-qtv15w.bzing the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 k2* lhn+l yicq3g 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 STPdssh 2q2rh.3q 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 helium gas is at 10.ybt6h km,o) xo(; (; rmivrem,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 insidahajr.*f j+y2 xxp5wk9sd :vj x+q7j/e a 35.0-L container holding 105.0 kg of argon gas at 385 K+axxfs+*awqh jvyjk. /xd:7r p29 5jj?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg of q :yt nftk 6yz v2c;/eb/-yeb,$O_2$ 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 theu4k no9 ljsy5qi6b5 3t air inside the balloon, which makes it less dense than the air outside. Suppose the vo35oj69lb4qt5 yikn uslume 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 with1 elkhpa(..an air at 15 $^{\circ} $ C to a gauge pressure of 220 kPa. If the tire reaches a temperature of 38 $^{\circ} $ C, what fraction of the original air must be removed if the original pressure of 220 kPa is to be maintained?    %

  If 61.5 L of oxygen atka -9vft/pa0x 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 escan:xyz13,; f dgkxj6 klpes a child’s hand at sea level and 20.0 $^{\circ} $ C. When it reaches an altitude of 3000 m, where the temperature is 5.0 $^{\circ} $ C and the pressure is only 0.70 atm, how will its volume compare to that at sea level?    times the original volume

  Calculate the number of lab) l(kgq 5f*molecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How nlx8 dab j-ucz4:vh*-ymt8 v 7many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) mwjifpr .a-x:9oles,    $ \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 56,b tvmtoc-3 ddxdm )7.1$ \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 molecs cwto4gn646dfx8r6dmd d7f74 h nn8g1eo st.ules of air are in each 2.0-L breath you inhale that were also in the last breath Galileo took. tgo47d x 8o4cf6d dfg w14nd 6.6en8trs7mnsh[Hint: Assume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic ee)b4mf yt/wxe -gargb hz; *77nergy of an oxygen molecule at STP? bg*/- b7xz 4 ge )mhre7;ftayw   $ \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 of78fixwxm x.e (2in+rd helium atoms near the surface of the Sun at a temperature of about 6000 K.n.dr7i e +8xxmxf2iw(    m/s

  By what factor will the rms speed of gas molecules increase if the temperat4mlzw7 zt7b. lure is increz7 74bw.l mtzlased from 0 $^{\circ} $ C to 100 $^{\circ} $ C?   

  A gas is at 20 $^{\circ} $ C. To what temperature must it be raised to double the rms speed of its molecules?    $^{\circ} $ C

  Twelve molecules have the following speeds, given in units of km/s: 6, 2, kc3qyf,o sl1 qp2 g;8q4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calculate the rms speed2qkl 1y;co, gp8 q3fsq. $v_{rms}$ =    km/s

  The rms speed of molecu42 vaxs:uq:ciles in a gas at 20.0 $^{\circ} $ C is to be increased by 1.0%. To what temperature must it be raised?    $^{\circ} $ C

  If the pressure of a gas is doubled while its volume is held t9ty45d x*h uhm (r cg06ybrw0:c* xhxconstant, by what factorhgwt 5x4y0yb :c6(h0xt c*x ruhd*mr9 does $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is given by d c97.i k6l;f 6drrozc$v_{rms}$ = $\sqrt{3P\\rho}$ 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 temperature, the ratio ox-ubj k,hmc ib5 1nro90h el(uq4 f6p1f their rms speeds is equal to the inverse ratio of the squa1cuqm r6xb1iehkuo ,9f5bjp -h 0(nl4re roots of their molecular masses.

  What is the rms speed of nitrogen molecules contained in ayhtykxk9r3s r:via,6+:5z9yyrf hp 7n 8.5$-m^3$ volume at 2.1 atm if the total amount of nitrogen is 1300 mol?    m/s

  Calculate (a) the rms speed of an oxygen molecule at 0 usuzz b 4(f7kpi)i7g 7$^{\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 44zvv5 zmg.e bn.)ho,ur x4 vvdistance between nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular mass is 89xgg,po iui.w5/u wx.8,2jeg m u in a living cell i.w5e, p2 wgugg x oi,/.m8xjuat 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 ofw 55p:jdi kql, a gas can be written P = $\frac(1)(3)\rho v^2$ where $\rho$ is the density of the gas and v is the rms speed of the molecules.

  The two isotopes of uranium, 3js yt zwo(6q.6o)rq a$^{235}$U and $^{238}$U (the superscripts refer to their atomic mass), can be separated by a gas-diffusion process by combining them with fluorine to make the gaseous compound UF$_6$ Calculate the ratio of the rms speeds of these molecules for the two isotopes, at constant T.   

(a) At atmospheric pressure, in what phases cadb+7gl71qq*d f4j)vbpx s tc1n $CO_2$ 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 0.0hxw/q8qdioz m/ 03a d41 atm and the temperature is (a) qixw// 34mdhza0 8qdo90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidiv0 q,9y1jutl* mdl dd3ty is 50% on a day when the te1ydt39j dldl0m* vq,umperature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressurevd.n4bi7ouv du. r8x, at a place where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is 0.72 atm, estimaeji:t5 s98f mote the tempers895em :j ftioature at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the p5fy; cz) oz) tce)kje8artial pressure of water is 530 Pa and the relative humid))k f5)yecozez;8c jt ity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the tiz0oeh w*q.q7emperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure co+y/ k -j1u)y:hygpec ioker if the water is boiling at a t:y1-e ukgyyi /hc)j p+emperature of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a roombe 13c(*zvwt f 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 * i j9mipm1*4jxf5 vuapoint of 5 $^{\circ} $ C is drawn into a building where it is heated to 25. What will be the relative humidity at this temperature? Assume constant pressure of 1.0 atm. Take into account the expansion of the air.    %

  Estimate the time needed for a glycine molecule (see Table 13–4) to 9r,sxs4tuw4i diffuse a distance of 1ixrws u9s 44t,5 $\mu m$ in water at 20$^{\circ} $ C if its concentration varies over that distance from 1 mol/$m^3$ to 0.4 mol/$m^3$ Compare this “speed” to its rms (thermal) speed. The molecular mass of glycine is about 75 u. t $\approx$    s ([color=rgba(0, 0, 0, 0.85)]Round to one decimal places) $v_{diffuse}$    $ \times10^{ -5}$ m/s
$v_{rms}$    m/s

  Oxygen diffuses from the surface of insects toyhz40 f)1;d wdqd wg*s the interior through tiny tubes called tracheae. An average trachea is about 2 mm long and has crossydz w;w40 fsh1)* qdgd-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 ha;-:o6tysp :4u dcrylw s 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 2(tfn yy,f l93slln+byve 1w)jo)y85i 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 normal room tex 4 d bzv4ai4nmnj38(mmperature. How much error will be made in a recipe calling for 300 mL of cool water, if the water3d8z n(4n4mij 4vxmab 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 he7 /shg jw(d+wplium gas cylinder is initially 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of (hd+jw /w gp7sthe original gas remains in the cylinder?   

  Estimate the number of v c6n-+aqj +qwdmk/ 7aair molecules in a room of length 6.5 m, width 3.1 m, and height 2.5 m. Assume the temperature7/6q+jand -am cw q+kv is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of 7v) 4px;iw3nhhxuu h; matter 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 vacuum teuagx08z6f e. achniques is about a 6ge ufza.0x8$10^{-12} N/m^2$ 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 ca8xbgmb. 5dv+5isfwe 7pacity of 5.5 L when 10 m below the surface, to what volume would his lungs expand if he quickly rose to the surface? Is5b mxif8.b7+5vde wsg this advisable?    L

  A space vehicle returning from the Moon enter4po +v vsq8rp/s 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 r + vs/8ov4qppof 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 in(rr0ghn. n*0 d:(y nh orrc b2)c9nctacreased 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 ofj+pdf ;oa* gujt0 l0d0 2rv6cf 770m$^2$ (a) What is the total mass of air inside the house at 20$^{\circ} $C?    kg
(b) If the temperature drops to -10$^{\circ} $C what mass of air enters or leaves the house?    kg

  From the known value of atmospheric pressure at the surf 0y yxbp (wj6p)w+t+oqeh-*aw)eyna0ace of the Earth, estimate the total number of ainj+y)t6(heo p0wwa)0a xwpy + b*eq- yr molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of rdundgo ,fc ze-x +4i:m 3pd4t4e +o5bnitrogen molecules contained in a 7.6$-m^3$ volume at 4.2 atm if the total amount of nitrogen is 1800 mol?    m/s

  A standard cylinder of oxygen used in a hospg a(fb i*kiq0-ital has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will th i0fkiqag- b*(e 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 of liquid mercury at 03jo*3 qb(njjz:f4w bp2g :rvu9ck c:1rw 3utj$^{\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 dvcwdk:;7:gjmp*.i6nw2 n+ luo q e0jat 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 around the Earth’s equator atzgt*2llo8 9uyq 0 gyy syt.k76 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 tov5nifl 7 kt:,ightly 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 standard, adopted in t4 n yg xwxz;,/gb-bzg1he 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 ccss7y;+pn eamho4, ;h harged, 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 theb** obg lu c4pozc7 v 46k-pl+(0osqlx 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 gravity by mptet;cnr6 :;c,us(upn n-v2 tennis balls thrown vertically upward at it. How many tennis balls per second must rebound from thcpur,6 u: c2n-; ttmnv;ne(pse 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-diameter (spherical) bubble of air fko ys;fs .v :5*q zl6ous7dx ;b/yny3hrom a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the air behaves as a perfect gas. How large is t.y*fss y7bvzuo;5hd/qk:s3 o n6 y;x lhe bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure in ther0gaiuy;8ti dmr 8dm/taq),3 air on the following two days: duamt y08;gitqd)8ia/ ,rr m3
(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 differen2amxxuk. -jl 9ce in the density of iron at STP, and when it is a solid deep in the Earth where the temperature isxukjl2x .-a9 m 2000$^{\circ} $C and under 5000 atm of pressure. Assume the bulk modulus (90$\times 10^9N/m^2$) and the coefficient of volume expansion do not vary with temperature and are the same as at STP.    %  ----待选择----decreaseincrease 

(a) Use the ideal gas law to show that, for an ideal gas at constant pressure, k x49 qpmv4v:3h wdz+lthe coefficient of volume expanxv3+:vwzl 94 qdpm4khsion 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 constantdss8g 9n2/; wugo/ik6 ;lnw2r gbeb k35 tr9eoly dehumidify their cellars to prevent rot and mildew. If the cellar in a house (ked6 r ;ouw bn8be39g/2k9eks;n ggi lw/ rst25opt 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