Which has more atomsshj)/2lni 6xyh 8w) ld: 1 kg of iron or 1 kg of aluminum? See the periodic table o6niyxdl 8hw2)/ js)lhr Appendix B.

Name several properties of materials that could be exploited to make a3yu 3*vm+nha s thermometersnyma*h3+v 3 u.

Which is larger, 1 C0y1j ehg3mgz+ $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, bfi+f.mf,aty*g h q d42ut B is not in thermal equilibrium with system C, what can you saha td.*ygf2imfq4 ,+fy about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted tocwlk/q/41w6 kp el1m ( p y(lis*rhyo/ a strip of iron. When heated, the strip will bend. Which metal will be on the outside of the cur( plyw6ce1 /l(qp4sl *k /m1hikwoy/rve? [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 coeffu nwad9xd jefs,*py4 fj2;3b( icient 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 simjl) a: 7lmjgq)ple thermostat used to control a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch is a glass vessel containing liquid mercury that conducts electricity when it can flow to touch both contact wires. Ejl lqg) mja:)7xplain 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 havec1(,nro/ awi) r3s jwg a section in the shape of a1ao,)w3r/ insjr(wg c U. Why?

A flat, uniform cylinder of lead floats in mercury ath1fuhx ua4v pdr6(e:l cv(j:4 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass hafm.1*pi421z,m0,nf tc v3tdkmlrg thermometer is first placed in a hot tub of water, the mercury initially descends a bit and then rises. Ehkn tm,d, lm4i10m3*f crat1gz p2f.vxplain.

A glass container may break if one part of it is heated or cood0rf+feo z.n8led more rapidly than adjacent parts. Explaiz+d0 f8nf.e ron.

The principal virtue of Pyrex glass is that i/n sns,ht+g3gcj* q1e) 7mjfc ts coefficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise toe,fn q73)*jtcg hs1 sg/+njcm the increased heat resistance of Pyrex.

Will a grandfather clock, ac9gwvt2e 2 b + uunfppkm85*3 (1flcjiecurate 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 buyd-07-s rk2hvzh*y;w laqy : ottom and top to bulge so badly the can will not stand up. Whv:w y h;-ds2-7yuh*k alyqrz0 at has happened?

When a gas is rapidly compressed (say, byyb q.5 (q1 1fzplnklz6 pushing down a piston), its temperature increases. When a gas expands against a pistn .fb1zq6zqyl(1l kp5on, 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 piston.

Will the buoyant force on an aluminum spherlb e vnlg eeh9q 04/2osd92q:ie submerged in water increase or decrease if the temperature is increased from 20 vlqe929eido/g 4:qebs nhl 0 2$^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Cha)m sbi00nn9yq rles’s law follows from kinetic theory and the relation between average kinetic energy and the absolute temperature. yb n0i9)qs0nm

Explain in words how Gay-Lussa2wr)bju id eb)9:/agy9;6cw m r2y nblc’s law follows from kinetic theory.

As you go higher in the Ear u2zlz9*/epsjost1g4ex ,) htth’s atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the orn(a f.:;.b;hkqcyr xclb9)Earth refers to the minimum speed an object must have to leave the Earth and never return. The escape velociq k.bb lxf(;;:n haroy). c9crty 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 t 107tmu)u v0jgcpugu4han water at room temperature. What can you infer g7umvgt01cu)j04u pu about the molecular properties of one relative to the other?

Explain why a hot humid day is far more uncomfortable u apipqny4+;,er knu4y jlj0 :-jc4+bthan a hot dry day at the same temperatcju+a n4 pb u0yy-4npk,4 eij:j;l+rqure.

Is it possible to boil watevvvsl5esf 0h;-ubp0i j3a;r1 l 2 ik3hr at room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the humidity is f-r jy).mwv-aiypu,4 different. Which is more dense, the dry air- j w-ymu.y4 ,r)pfiva or the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap of an overhe7 bu ctg cn1.n2:qq-06mr gmuxated automobile engineuq q2btnucm.xm 1 r:gnc -g760.

Why does exhaled air appear as a little white cloud in the f-um-g ,h om.mwinter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram coppeg gufi,bp9zq;49/mf0y7h dmur penny?   $ \times10^{22}$ atoms of Cu

  How does the number omh.)pv ;sxs -gte2 gh.f atoms in a 26.5-gram gold ring compare to the number in a e ..- mhsgghpt;2)xvs silver ring of the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this on the Celsius z hzx bm1y8eo0(,x,y-me8 mg, ee4qypscale?g(o , ,hq8pmm,4zez8xe- 1xby yeemy0   $^{\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 recorded aef;0qlfbzm4 + re 136 $^{\circ} $F in the Libyan desert and -129 $^{\circ} $F in Antarctica. What are these temperatures on the Celsius scale?high =    $^{\circ} $ C
low =    $^{\circ} $ C

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

  In an alcohol-in-glass thermometer, the alcohol column has lengto k -1qbf0 4heewq:6luh 11.82 cm at 0.0 qoe1-6 wf: 0uq4helkb $^{\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 (25r*0cjjwfi0(vz ; eda3nd ul 8+er ;gt0 $^{\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. 4aiv(, sycz r(13–29) is built of wrought iron approximately 300 m tall. Estimate how much its height changes between July (average temperature of 25°C) and January (average temperature ofa(z, (4 cyvris 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 use gqqcpv6q2+6vdh*gx 0v7sy; ed and the rivet is cooleqcx0vd; 72vph sy* +6eqqg6v gd (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 y)b0mx ; dvk2 q01o3rj 0dfgt.jkkqp+ at 4 $^{\circ} $ C is $ 1\times10^{3 }kg/m^3$ What is water’s density at 94 $^{\circ} $ C?    kg/$m^3$

  A quartz sphere is 8.75 cm in diameter. What will be its change i.1rsnpvc8h9j9 qb9vdn volume if it is heated.9v s9dcjn r89h1pvq b from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is fi2 n6lhm/ppwo2 +x)clqcq 8+ iilled 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 at,yr6r07 +mahlji a 7hg 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 ipt ;f 1adv:jh0nyd 9jq,3*ppln 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 vessel so it can expand in 7 mwvf kdg3.758i)or pq2untyessentially one direction only, show th.7 td2r5pomui7ng)8 q v3wfykat the effective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the den/l 6c8doppy*io3 9wqvsity $\rho$ 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 has coefficientn bc.ninea 7wwh:.3 y2 of linear expansiowanyi w3.:b2n7.h cen 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 isotropic s+ jnb2a/ +cwxmolid, $\beta$ = 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 is8kly42(+7s bne9nmlh art+p9 1 fssmv made of brass and keeps perfect time at 17sv94h r2t +mne 1kap9(n8 lym sf7sl+b $^{\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+:+9h nwtwz)cnb:xk m thermometer has an inside diameter of 0.140 mm. The buzb wm +:h):+k9tnncw xlb 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 aluminum cylindrical wheel of radi0-tw8+ zu tgldv1, 4nm nd,l5c koht0ius 0.41 m is rotating about its axle on frictionless bearings with c,gdt0h0m + li1tdun,- 5tznvw4k 8ol 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 r*fjbi x7 bp0xoe-q-r2equired to keep it at this length if the temperature incrrqfx--jp2eo7*i0 b xbeases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cronph yx8;czp.1v /8 v /gxjnu1nss-sectional area 0.041$m^2$ is rigidly connected to two vertical steel girders. If the beam was installed when the temperature was 30$^{\circ} $ C, what stress is developed in the beam when the temperature drops to -30 $^{\circ} $ C (b) Is the ultimate strength of the steel exceeded? (c) What stress is developed if the beam is concrete and has a cross-sectional area of 0.13$m^2$ Will it fracture?

  A barrel of diameter 134.122 5-;j6 2cmlsj/ jjck;s6lk s mscm 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 pb wgc.(sh71myow,dzf6s8a+ temperatures 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 whate; y2fvgf) 1z 4rgw.x vvy2vc1 temperature on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in tg86mh u((eapjv a3t;v x 6.zoqhe 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, airx9l rd0kvn;+ j2 yojma9lq/ 6d at atmospheric pressure and a temperature of m+2kn/d9 ;qj0r9oxa6lyvj dl about 20$^{\circ} $C is compressed in the cylinder by a piston to $\frac{1}{9}$ of its original volume (compression ratio = 9.0). Estimate the temperature of the compressed air, assuming the pressure reaches 40 atm.    $^{\circ} $ C

  Calculate the density of oxygen at STP using the ideal gasguqww.y/(f1yp8 n.auoc / g0s law.    kg/$m^3$

  A storage tank contains 21.6 kg rdb ,dfzni7 w 67r9njo;aw-0n 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 18.5 kg ov2 zmo8d(hsm scpy05*f 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,wfxz +mpi (8ku1 +fkqp-xlx; at 10.0$^{\circ} $C and a gauge pressure of 0.350 atm, (a) calculate the volume of the helium gas under these conditions.    $m^3$
(b) Calculate the temperature if the gas is compressed to precisely half the volume at a gauge pressure of 1.00 atm.    $^{\circ} $ C

  What is the pressure inside a 35.0-L container+ -iffnt 0b kbap i:ycr,*wf2- holding 105.0 kg of argon gas at 3-bkf:2a n*f, rc-wtibyf+ip0 85 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kvo,aznil 7( p3g 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 ball4jtac6+ i 2 c1lj*eeguoon, which makes it less dense than the air outside. Suppose+c uae61l2 gie*jcj 4t 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 1z h/ qj g8lvizxf::iy/b8oru8+(of5m5 $^{\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 1qhgu h s/il9 l)j ;;6rlkw+x5e8.0 $^{\circ} $ C and an absolute pressure of 2.45 atm are compressed to 48.8 L and at the same time the temperature is raised to 50.0°C, what will the new pressure be?    atm

  A helium-filled balloon escapes a child’s hand at sea leve*ifyoq:d8o .x l 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 molecules-o*3 )mi sjwy-xq,:vzj) hwc q2gcvd ; / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 wa(tqg- * 2hgj,fz h2kL? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) molem5ei1u n a1iz-s,    $ \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 volumb 3m0 eq/phskz:ry7;x e 5.1$ \times10^{ -2}m^3$ is filled with air at atmospheric pressure at 20 $^{\circ} $ C. The box is closed and heated to 180 $^{\circ} $ C. What is the net force on each side of the box?    N

  Estimate how many molecules of air are in each 2.0-L bdn -7.g-7 4 kvwg1wlhb;wt omwreath you inhale that were also in the last breath Galileo took. [Hint: Assume the atmosphere is about 1do1 l4 v.w tw77;g ngwkbh-mw-0 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average tran;7fcelpqw e9 (slational kinetic energy of an oxygen molecule at STP(wl 9ef qp;7ce?    $ \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/ zio2tuhos0chs(pgomd0 f 6l v88.s3 of the Sun at a temperature ohs6u( s0 3oic0ld/2tpog8 vo8mfhz s. f about 6000 K.    m/s

  By what factor will the rms speed of gas molecules increase if the temperaturhzci*:irp/)+s od8v ke is increased from 0 r sihz8ki)p+/:do c*v$^{\circ} $ C to 100 $^{\circ} $ C?   

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

  Twelve molecules have the following speeds, given in units of km/s: 6, 2, 4,mtz 8vqhe2 pj ;0rt2-u 6, 0, 4, 1,r-0j2e vz;t2qm tu p8h 8, 5, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gasdf+ih29 7 d;z k 8pdr6egpd(jh 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 an69p9fiixu6/+ iqf u constant, by what factor does /qu9 +iui6p 6naxfi9 f$v_{rms}$ change?   

Show that the rms speed of molecules 47ea;,u3ysje7b7 koofdbgb /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 temperature, the d w06l 4od*emwratio of their rms speeds is equal to the inverse ratio of t*dwlm 4wo60ed he square roots of their molecular masses.

  What is the rms speed of nitrogen mxjp(c1oaflc0ns 99 8p olecules contained in an 8.5$-m^3$ volume at 2.1 atm if the total amount of nitrogen is 1300 mol?    m/s

  Calculate (a) the rms speed of an oxygen molecule a sq1vwza l 5nmb5k3h*vgm*ofg 20;g f3t 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+ 9 hxwn; vs2c:lojbj6 between nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms spey q8z g:rkz-ir, jyj8rkh;*3q ddg,4aed of an amino acid whose molecular mass is 89 u in a livin-kyra j*,zj8d 4q rq:r83gz;gdkiyh,g 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 be writte .pm dn vbkxy4:q/yg4wv(pu 45u7m1m bn 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 uranigpl j 5eo;j1;8bu sk/bum, $^{235}$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 ei4u, ) r 4me-pm0nhu1yqke7hwhat 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 eo2 .agzy :jh; 6n)arzthe pressure is 0.01 atm and the temperature is (a) z6hzaagrj;.2 o)ey:n 90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximatea g6*v1oh ,lngly) if the humidity is 50% on a day when the tog*6agl1hv n ,emperature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place whe3, ii:b q9pphq05kywnre water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is 0.72 atm, estimateo6 e3mtp2f9gsw 5 5kpd the temperature at wh52fp g6wdse5 kpt9om 3ich water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a dayej kqe.i,yzkuj/qq7b*g 77(g when the partial pressure of water is 530 Pa and the relative humidity is 40%?/ j7g,.i(e zj 7qqkb7egq*yku $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure oj.*7bt*ec,v2nen k8r ik warw* rx2g; f water on a day when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate psa2/ od+bf7tl ressure inside a pressure cooker if the water is boiling l7oft+2d ab/s at a temperature of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in akbb 9guxq+id q9.:gxtg) f.3y room of volume 680$m^3$ at 25 $^{\circ} $ C is 80%, what mass of water can still evaporate from an open pan?    kg

  Air that is at its dew point of 5 vqirc09wt p7v. 2.70kan trlf$^{\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 diffuse a in-6tiq+hq9z wx4 ew- 1laa6ldistance oft-newh9qlw ax z-1+a64i l6iq 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 througsa o2kt:lw9 ,xh tiny tubes called tracheae. An average trachea is about 2 mm long and has crosawt:x9 2,kosls-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 can bvu)xiyd2f/ xlu6(t +ak9h+librated 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 calibrat lwzhebl,a,2d o/9zx4/x lof-sle 7z7 ed 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 atcu7bc 7+wlhu : normal room temperature. How much error will be made in a rwhcu:77cu l b+ecipe calling for 300 mL of cool water, if the water and the cup are hot, at 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in a helium gas cylinder is initi/wm5bdf.t z n8ally 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of the original t bwdzfmn/5.8gas remains in the cylinder?   

  Estimate the number of air molecules in a room of q 6+vd nr2tur p0,gosv7i+ly;length 6.5 m, width 3.1 m, and heigh vs,iudgq yl2n;p0r7+rv+6tot 2.5 m. Assume the temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is about oeul5 s ks1*t2jne 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 vaarh uf k6;d,cz6gbw86cuum techniques is abod6r;, h6zckbwu 8agf6ut $10^{-12} N/m^2$ 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 L when 10 m belowhk*u :xvpch7m6;2 czw the surface, to what volume would his lungs exp cm2wx*ch;zp6 uvkh:7and if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Mopt mft *sp9e4um(ih-orq-)h+ 5um+kjon enters Earth’s atmosphere at a speed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this speed correspond to what temperature? (Because of this high temperature, the nose of a space vehicle must be made of special km+q+ - htum f-p5m*s(he4)pr9tuoi j 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 incix.ymi;o d+; atahy 2rra)91k 6(nkb freased 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 776 /)mylo9jcnh 0m$^2$ (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 t;p,(xo/b+mylof utq5 pg 3 g4uhe surface of the Earth, estimate the total number of air molecules in the Eary3fxq+5tg4loo ;, (m gpb /uupth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contaznu/noiq- 159q;:yt g8n d mcqined 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 lv5i09;b f ylqof oxygen used in a hospital has gauge pressure = 2000 psi (13,800 kPa) and bil l0yf9;q5v at 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 of liquid me5x uzgo9c53 jv+6fc zercury at 0$^{\circ} $C. (a) If the temperature is raised to 25$^{\circ} $C, will the cube float higher or lower in the mercury? ----待选择----lowerheigher 
(b) By what percent will the fraction of volume submerged change?    %

  The density of gasoline a66um9vo a pr 4lzpyz-c4s(+ bucml,3ft 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 fitpfg3 s;+v0nvl 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 f 3w z fi;zp3nwgen48*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,e3o+j uu+:gwg2wj8 .j:uzfoi adopted in the 18$^{th}$ century, was a platinum bar with two very fine marks separated by what was defined to be exactly 1 m. If this standard bar was to be accurate to within $\pm1.0 \mu m$ how carefully would the trustees have needed to control the temperature? The coefficient of linear expansion for platinum is $ 9\times10^{ -6}C/^{-1}$. $\pm$ =    C$^{\circ} $

  A scuba tank, when fully charged, has a pressure of 195 g 0v;ezjz. -dpatm 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 iwn n786g jhwf :s2mk;the Earth is $ 1.12\times10^{4 } m/s$ so a gas molecule travelling away from Earth near the outer boundary of the Earth’s atmosphere would, at this speed, be able to escape from the Earth’s gravitational field. At what temperature is the average speed of
(a) oxygen molecules,    $ \times10^{5 }$K
(b) helium atoms equal to $ 1.12\times10^{4 } m/s$    $ \times10^{4}$K
(c) Can you see why our atmosphere contains oxygen but not helium?

  A 1.0-kg trash-can lid is suspended against gravid rfz8s*yq+y0ijh fwppsn5oax 2 6 *:4ty by tennis balls thrown vertically upward at it. :*snjfydf2qy *i8 psxoa6r54p0w+ h zHow many tennis balls per second must rebound from the lid elastically, assuming they have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00c;;wdj.g6(m sx f4yws-cm-diameter (spherical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the air6;m cdx.sw4 wyj;s(gf 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 okwk rp1d3 *g5nn the following two days: np*1rg d3wkk5
(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 difss(isa*)lwbwnb kg d52x 8..l ference in the density of iron at STP, and when it is a solid deellbi5(sw xw)g s*n.sk8a b.d2p in the Earth where the temperature is 2000$^{\circ} $C and under 5000 atm of pressure. Assume the bulk modulus (90$\times 10^9N/m^2$) and the coefficient of volume expansion do not vary with temperature and are the same as at STP.    %  ----待选择----decreaseincrease 

(a) Use the ideal gas law to show that, 51 yxn*gbd ki67vb9ulfor an ideal gas at constant pressure, the coefficient of volume exp* b5n 6bv klyugd791xiansion is equal to $\beta$ = 1/T where T is the temperature in kelvins. Compare to Table 13–1 for gases at T = 293K (b) Show that the bulk modulus (Section 9–5) for an ideal gas held at constant temperature is B = P where P is the pressure.

  In humid climates, people constantly dehumidify their cellars to prevenorl6 jbi+to c-j3o/2 g4xtv 5wt rot and mildew. If th 6 cj3btroo g2-ij+xv /l5o4twe 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