Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodic.jk v8nex8g-v table or Appendek8 8xjgv-vn .ix B.

Name several properties of materials that could be exploited to make afo8p8)f ht/zd thermomet/t8pfh)d f 8zoer.

Which is larger, 1 C sbxjyjo8f1 q ;*h58k f$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system;/*uf,3fkw-xysdds, sku (zrp c r;;h B, but B is not in thermal equilibriumf;u-fp3*syus,d kwc,sk; zxrrh;d( / 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 i,i ytq vwagy0;wv3 cqwl u/ey*y;+/v-ron. When heated, the strip will bend. Which metal will be on the outside of tw/ww;ly;/e+y* y- 0uvyigv ac t,v q3qhe curve? [Hint: See Table 13–1.] Why?

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

The units for the coefficient of linear expah6 k8 l1u6mbanb23dhq nsion $\alpha$ 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 furnace (oa.s;,b5dx-sdenwe 5 e zycy5,r other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch iss 5de-we,sdz5yab ne;x,c5.y 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 a;qi 4/)wc77 (rep cw/lydc xaxre fixed at the ends often have a section in the shape of a U. Why? c7 ewx/iyrxc(a;dwq7pcl/ 4 )

A flat, uniform cylinder of lead floats i y z3- md7b.mp1kka*o.o)pihqn mercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometer is first placed in a hot tub of w7 h74d9vtva18iq4vb l jysp0 xater, the mercury 7va q vtbsv0i414jp h8d79ylxinitially descends a bit and then rises. Explain.

A glass container may break if one part of it is heated or coolwmv9;j, b b.rged more rapidly than adjacent v w.b9gbmj ,;rparts. Explain.

The principal virtue of Pyrex glass is that its coefficient of linear expansi 3rqs/x: xg:4s uala1kon is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Psxkg l3a1 4q a:sxr/u:yrex.

Will a grandfather clol68 ixqk3yr :5,rok7 wi7uyvwck, accurate 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 wilarb dtlc )b1is. (4w;ll cause its bottom and top to bulge so badly the can will not stand up. Whatdb4w t( ic ra)sl.1b;l has happened?

When a gas is rapidly compressed (say, by pushing dow,d6ilk/kpj uvj.6 d*rn a piston), its temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperature using the kinetic theory, in particular notingj.*d6i6 lr /p dkju,kv what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force on an aluminum sphere submerglsvu*ii43i u/ ed in water increase or decrease if the temperature is increu3li*v / usi4iased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theory and the u;, wmte6o7hzvf;o5f )bx) xirelation between average m6) v,7)oohxti;b fxuf ew5z;kinetic energy and the absolute temperature.

Explain in words how Gay-Lussac’s law follows fr o.r :ei8a, +*umtazbhom kinetic theory.

As you go higher in the Earth’si i 8ve-0(oxzyex 63lk(e6ny)v.x xga atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed an objecy z86 5cz-ym. ay-tvcst must have to leave the Earth and never return. The escape6ztz.cmv5cs- y-y8 ay 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 roo z0ehr6qvulyvipp a.* ry7s +co z:328m temperature. What can you infer about the molecularoylv6 v2u 8h ri.70*r:zpp3+z aqcy es properties of one relative to the other?

Explain why a hot humid day is far more uncomfortable tha87e7mb; b ,cnnot ;gckn a hot dry day at the same temperme7b,n78 cbgkcn to ;;ature.

Is it possible to boil water at r.wnq vee( eduoj:,2 ;h4pjk-w oom temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the aep 4ezr5qbd) fpk c)5(p+k) ydir temperature is the same but the humidity is different. Which is more 5zebq yke 5p) 4)d frp(pcd+)kdense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerousz,-knh1 r;bg mp/v4nk to open the radiator cap of an overheated automobile engin;zhv1 rkmn -bpn4gk, /e.

Why does exhaled air appear as a little white cloud in the winter (Fi3s)rfhd -u;rl g. 13–28)?

  How many atoms are there in a 3.4-gram copperg6 ak 9fyd ;tnigj7h)8 penny?   $ \times10^{22}$ atoms of Cu

  How does the number of m(v0ga 4p: xwito9gg6-hh(sn atoms in a 26.5-gram gold ring compare to the number in a silver ring of the same m(m gh06:- xgstioh9 apvgw4n(ass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68ab+uo: bzn)3i °F. What is this on the Celsius scale?bu+b)i:zno a3   $^{\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 temperatureso9 -s(;n5v ofelz g(ew 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 knq)/0at 0 nsxusu**u, the alcohol column has length 11.82 cm at 0.an/sn00 uu tx**s uqk)0 $^{\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 builw(/kms. j7k iqt of slabs 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. 13–29) is built of wrought j4g;t1nin y6je*: kux* lbsp,iron approximately 300 m tall. Estimate how much its height changes between July (average temperature of 25°C) and Januaryln6kxp,e:jyt jn;g1 siu4 *b * (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 rivv6;5p1kj ltip et hole are often used and the rivet i tlp5j6 ;1pikvs 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 ,8iy g;pnlcg 2 eu2lu:zz198a)kb trv 4 $^{\circ} $ C is $ 1\times10^{3 }kg/m^3$ What is water’s density at 94 $^{\circ} $ C?    kg/$m^3$

  A quartz sphere is 8.75 cm in diameter0+dhu, u:gwvl. What will be its change in volume if it is heated from lv,:+hg d uw0u30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 39 baxt;4wob,n 50.0 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 +s)o ea8p5jnw9ziqhl. ,b;.r q+ moht+dgtt755.50 mL of water at 20 $^{\circ} $ C completely fills a container to the brim. When the container and the water are heated to 60 $^{\circ} $ C, 0.35 g of water is lost. (a) What is the coefficient of volume expansion of the container?    $ \times10^{-5 }$ /$C^0$(b) What is the most likely material of the container? The density of water at 60°C is 0.98324g/ml.

  (a) A brass plug is to be placed in a ring made of iron. Atyqx9d qk ad)/z o51nk, 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 e1: m9bfr oh9ovessel so it can expand in essentially one direction o oor91fm9:ebh nly, show that the effective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the density i 3b0rz-+p 4w2ciwej2nvrkc 2$\rho$ 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 placzz:ycoo)h/;q+, z) lzm ma l:te of length l and width w has coefficient of linear expansion :z zczolc/lm)a,y):+ozm qh ;$\alpha$ 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 iso0srx i3je f;nh42mx:qtropic 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 of brass an-dckakh2v a52q2bi ;xd keeps perfect time at 175cbkx ki;2avhq2 -da2 $^{\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 inside4 ky9fczd9 r;t 26og.n0 etqco diameter of 0.140 mm. The bulby 0 g n.q46efzcd9ot9rk; o2ct has a volume of 0.255 $cm^3$ How far will the thread of mercury move when the temperature changes from 11.5 $^{\circ} $ C to 33.0 $^{\circ} $ C? Take into account expansion of the Pyrex glass.    cm(b) Determine a formula for the length of the mercury column in terms of relevant variables. Ignore tube volume compared to bulb volume.

  A 23.4-kg solid alumin1of .p49 t94 txtdbmia2uj+mbum cylindrical wheel of radius 0.41 m is rotating about its axle on bi ut4at9o2d41m xftj9 pm +b.frictionless bearings with angular velocity $\omega$ = 32.8 rad/s If its temperature is now raised from 20.0 $^{\circ} $ C to 75.0 $^{\circ} $ C, what is the fractional change in $\omega$?   

  An aluminum bar has the desired length when at 15°C. How much stress iv xh o ;/iv9l 8fhp:unl14izf5s required to keep it at this lpx f91hfivl4lu: noiv ;h/z5 8ength if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-secti nvlax ,a/b87j eg(ri; .7bmevonal area 0.041$m^2$ is rigidly connected to two vertical steel girders. If the beam was installed when the temperature was 30$^{\circ} $ C, what stress is developed in the beam when the temperature drops to -30 $^{\circ} $ C (b) Is the ultimate strength of the steel exceeded? (c) What stress is developed if the beam is concrete and has a cross-sectional area of 0.13$m^2$ Will it fracture?

  A barrel of diameter 134.mwj7; kahi 4vr22bn3k+fsc9 a122 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 temperature z7i i 5 lxlu3toiao8*fk;9x;ks on the Kelvin scale:
(a) 86$^{\circ} $ C,    K
(b) 78$^{\circ} $F,    K
(c) -100$^{\circ} $C    K
(d) 5500°C,    K
(e) -459$^{\circ} $F    K

  Absolute zero is what temperature on the Fahrho 8 0ijw0qs,c;zjg h9.mfmbbx) c,v,enheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Ef4mp-yej7b; aarth 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 atmospheric pressure and a temperatuta;umaff- f61w.)t j xk 1l9lbre of aboutkbw61ft a.a9ul-tf)1fj m;x l 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 i8 jg.qzt;4 s30l )f99z*jwl lm ,upbbxysgub6deal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of nitrogen yxt3z r6i 4bu4($N_2$) 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 conbm*e) jbyq .5ghsg54uj xkc x 3v,4e6mtains 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 j jg)o s)m9a(p -vb4x1rde +y-hg9v.rypsy)o 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-ukir (.tk:nu(;( g k/tq zwud;L container holding 105.0 kg of argon gas at u;( gt;urdi qwk(/nkkzt(:.u385 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg ofoyu ts6 z 162klh,*/tv 9rfqlx,9vxli, y jro3 $O_2$ 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 m j. ne :4tpl41ipgn8xballoon, which makes it less dense than n8p4 n glmjt:e1ip.4x the air outside. Suppose the volume of a balloon is 1800 $m^3$ and the required lift is 2700 N (rough estimate of the weight of the equipment and passenger). Calculate the temperature of the air inside the balloon which will produce the required lift. Assume that the outside air temperature is 0 $^{\circ} $ C and that air is an ideal gas under these conditions. What factors limit the maximum altitude attainable by this method for a given load? (Neglect variables like wind.) $\approx$    $^{\circ} $ C(Round to the nearest integer)

  A tire is filled with air at u;t 9 7(diqwci15 $^{\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 18.m++,l3 ixkfmc 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 e+u6+ljy)w6 yps0sn .;wixmcs .ve i w1scapes 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 mol,jgcc-cbc 68 cecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water areesdx ji**n dk ms0s;fmc- )x(9 there in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) moleja90(yz i mc-ms,    $ \times10^{22 }$ moles and (b) molecules of water in all the Earth’s oceans. Assume water covers 75% of the Earth to an average depth of 3 km. $\approx$    $ \times10^{46 }$ molecules

  A cubic box of volume 5. 1cecsbp g r*c.* h+zxdxy+3x31$ \times10^{ -2}m^3$ is filled with air at atmospheric pressure at 20 $^{\circ} $ C. The box is closed and heated to 180 $^{\circ} $ C. What is the net force on each side of the box?    N

  Estimate how many molecules of air are in each 2.0-L breath you inhale that were 5qk57tya4p09zgs jd g alsok0a7sqp45g gzd9t 5yj 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 translation-5qds j3zhxb c7c8;2kdh9hpncr, p 4oal kinetic energy of an oxygen molecule at ST95oc3p2;chj pqh7d8kcb, z xr -dhns4P?    $ \times10^{-21 }$ J
(b) What is the total translational kinetic energy of 2.0 mol of $O_2$ molecules at 20 $^{\circ} $ C?   $ \times10^{3 }$ J

  Calculate the rms speed of helium atoms near the surface of the Sxe)1y /; dg0wvsdo7ncun at a temperatuvdye x1)cw odg/7sn;0re of about 6000 K.    m/s

  By what factor will the rms speed of gas moleculkicn ::88lapt es increase if the temperature is increased from:k 8 tapil8cn: 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, v tnimf8zahdxzfu + cc:*w(w644/*sa2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calculate the 4/ta+ *:mh(c*8xzsudfz 4 wa fvicn6wrms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in 0./hb2ptmime(o l pz)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 volumeamc5 yexk4wy(p7db)at591 1s/p zeqn is held constant, by what factor does)x19wek ynb ypmd/te1acqz54 7 5(pa s $v_{rms}$ change?   

Show that the rms speed of moleculx keiy0aq-oo, e9h(hi r*i,t 6es 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 temperahvnm91k:b vfo4x pu.;h u08x0dq y;ax ture, the ratio of their ;vufqp;xd10yx hv8m 0 9h4 .n:kxb ouarms speeds is equal to the inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen molecules cont i+dsm1l1+qb++ zlrxpained 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 / kfboilljo7- 7v3- nj+il,z kspeed 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 betweenn9 +dfhigs)8z nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed xl 1e cnf3pjw;t/.ym gm1(i af,d0ol8of an amino acid whose molecular mass is 89 u in a living cell at gj0 p38.c/d l(eay1xoilm wn;1, fmtf37 $^{\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 be written P = vvgi; (tbzt944i6pv i$\frac(1)(3)\rho v^2$ where $\rho$ is the density of the gas and v is the rms speed of the molecules.

  The two isotopes of ura 2vgj;xo i,xh;nium, $^{235}$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 pressurt8 www(0xbkltyv c8 f3xhmr.855 tq3je, in what phases can $CO_2$ exist? (b) For what range of pressures and temperatures can $CO_2$ be a liquid? Refer to Fig. 13–21.

Water is in which phase when the pressure is7qi2q7h brn2v 0.01 atm and the temperature is (a) i27qvr b2qhn7 90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity is 50% on a dayag3yz0xypt( / when the tegyp(a0y 3/ zxtmperature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water boils dgcb*+mmy-ugc d go 4tdh,( bt*,; 40gknmq d(at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is a0tkx-yte1uxf 71h ) td) 1)pz)gzgyi0.72 atm, estimate the temperature at which water dgxik ))g-1tpf1)uay t)17hztyz 0ex boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressur**m7 8ftjti ;p,jz kore of water is 530 Pa and the relative humidity is t kojjim,8p trz* *;f740%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of w,d: g h4ctbx)48p acbqater on a day when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cooker if the w9n57unirw1)/l kucb dater is boiling at a temperatnul bc / 719ik5d)wrunure of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room of volumhpqj ,q +6ht*ue 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 poza uqv,v*2.wv 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 molecule (see Table 13–4) te e)f0o w+kruh5i7 py8o diffuse a distanrfkeph5o8i7 uy0+ e)wce of 15 $\mu m$ in water at 20$^{\circ} $ C if its concentration varies over that distance from 1 mol/$m^3$ to 0.4 mol/$m^3$ Compare this “speed” to its rms (thermal) speed. The molecular mass of glycine is about 75 u. t $\approx$    s ([color=rgba(0, 0, 0, 0.85)]Round to one decimal places) $v_{diffuse}$    $ \times10^{ -5}$ m/s
$v_{rms}$    m/s

  Oxygen diffuses from the surface of insects to the interior through tiny tubes 0-1c;lmzm8q 96w9a lk mzpwwrcalled tracheae. An average trachea is about 2 mm long and hc 9aw1 zwkmmwmqp-0r9l6l8;zas 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 calibraq. jk003q+h zobg8v heted 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 measun 7-:,cmr utsn/c+epure has been calibrated at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A Pyrex measuring cup was calibrated at normal room temperature. How much eyssn/)y n nn 2rej:y+8rror will be made in a recipe calling for 300 mL of cool water, ) n:j 2+yys/eynn nsr8if 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. After mzuz.nuh;ml9mf7 4af( any balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of the or9ma.f4z uhmfnu;z(7 liginal gas remains in the cylinder?   

  Estimate the number of air molecul /0yjn* q8blbies in a room of length 6.5 m, width 3.1 m, and height 2.5 m. Assume the tem0nbj*b/ yi ql8perature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of may4xe2djh.;;a xnc *uptter 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 uscz.ykq24 lg.+2x9 eo v3omq7a* xromuing the best available vacuum techniques is about o..u cexoqyxql 2 zm2+*r3v94 gmoak7$10^{-12} N/m^2$ 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*l3r8yjv k3ov his lungs to full capacity of 5.5 L when 10 m below the surface, to what volume would his lungs expand io ykvlvj3 8r3*f he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmo6x0pbxpuo 1)a7k g n z/6t1zhksphere 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, part of it does vapori76hp)xo06txz1 u pg/ 1zakbkn ze, and this is seen as a bright blaze upon reentry.)    K

  The temperature of aaj8+;7pzfer b -tuh5cn ideal 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 770rdw zlg )u+es i4fj563m$^2$ (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 off,jk1kop9 ,r9bt5 m w 2xrt hu-vdeb+)xq9v j: atmospheric pressure at the surface of the Earth, estimate the total number of air molecules in the Earth’s atmospheebj+x tu,9rp)mwt,rkj k19v ov: 5dx fhq2b-9re.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules conc rs(wr(hto-7 tained 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 hospital has gauge pressure ,-1q y1exx)a, lfdjej = 2000 psi (13,800 kPa) and af1eqjxej y,x-) , 1ladt T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl y (ak/adb4v4q9ba0wj e f.jv4 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 gasol266 0u1er4pm taidqtg ine 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 were4 c4y7zg:se y wcypr*0 to fit snugly around the Earth’s equator at 25$^{\circ} $C, but then was heated to 45$^{\circ} $C, how high above the Earth would the band be (assume equal everywhere)?    m

  A brass lid screws tightly onto a glas0) kuj5 wr.rptby,ep 1s 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, adoptedy :k0zyr+4pyvi yo,vh ,1wu m-4s :png 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, hayxx a ob5w*bzzl9d*6r 9t y*(ws 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 the Ea zxy. g50qduf3rth is $ 1.12\times10^{4 } m/s$ so a gas molecule travelling away from Earth near the outer boundary of the Earth’s atmosphere would, at this speed, be able to escape from the Earth’s gravitational field. At what temperature is the average speed of
(a) oxygen molecules,    $ \times10^{5 }$K
(b) helium atoms equal to $ 1.12\times10^{4 } m/s$    $ \times10^{4}$K
(c) Can you see why our atmosphere contains oxygen but not helium?

  A 1.0-kg trash-can lid is suspended against gravity by tennis balls thrownqarhu +o h cpwss6/jq7m1 g +,r-bv;g) vertically upward at it. How many tennis balls per second must rebound from the lid elastically, assuming they have a mass of 0.060 kg and are 7qpgm;+ob auqss h+ cvgw1hr,j6-/ r)thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter (spherical) bf2ayxo))d.fm8p : gpvubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, an).2gm d8:xafopypf) v d 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 following two d1/4 c0mgzo hfmays: hzm1o c4 fmg0/
(a) a hot summer day, with the temperature 30$^{\circ} $C and the relative humidity at 40%;    Pa
(b) a cold winter day, with the temperature 5$^{\circ} $C and the relative humidity at 80%.    Pa

  A sauna has 7$m^3$ of air volume, and the temperature is 90$^{\circ} $C. The air is perfectly dry. How much water (in kg) should be evaporated if we want to increase the relative humidity from 0% to 10%? (See Table 13–3.)    kg

  Estimate the percent difference in the density of iron at STP, and- e)zjz4ipd(ov-g )aq. utxt9 when it is a solid deep in the Earth where the temperature is 200z-ogx ( e p9.ud))att-4jizv q0$^{\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 cowkh9i,u7igi2 qa3 qg 4es,kd5 nstant pressure, the coefficient of volume expansion is equkeu2 iqh4,asqg, idk735w 9igal to $\beta$ = 1/T where T is the temperature in kelvins. Compare to Table 13–1 for gases at T = 293K (b) Show that the bulk modulus (Section 9–5) for an ideal gas held at constant temperature is B = P where P is the pressure.

  In humid climates, people constantly dehumidify their cellal2a7gxm)b7x3c yx *jers to prevent rot and m3xb jlm*7ax7exyg )c2ildew. 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