Which has more atoms: 1 kg of iron or 1 kg of c bt )(e)r6el)4qdiy oaluminum? See the periodic table or Appendixc q)ir dol ey4)()6etb B.

Name several propertie ,, / j7vq59hna8wwhtugj 8rocs of materials that could be exploited to make a thermometwut ,5/ ahj 9qwjch8r,og7nv8er.

Which is larger, 1 C yv4ln ts.fnoy32dg; my2 czi4m (6+tv$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium w: qb -i i)mj;5ezryii8ith system B, but B is not in thermal equilibrium with system C, what cai;bq e 85m:-)iirj yizn you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to a3thj2 j/kjiz.5t2mon strip of iron. When heated, the strip will bend. Which metal will be on the ouokt/z3 5m jij2t j2n.htside 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 of linear expansio ery2vx;( s6g(*ghx eon $\alpha$ 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 furnao 3 x+8aup cg++wqio/t qsz+k+ce (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. Explain how this device controls the furnace and how it can be set at3+ ++a+cx soi/zwq g8tk+pquo different temperatures.

Long steam pipes that are fixed at the ends often have a section in t*z a1); -/s,1xaedtt vnn. lv ezm-qbohe shape of a U.asn*l1axt v-t qe.,n1b-vzm zed/) ;o Why?

A flat, uniform cylinder of lead floats in mercu o i;1wzu qt4bx)tgl9o*/iwl;ry at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometenne:sc gms8 (i/bz;+ur is first placed in a hot tub of water, the mercury initiz sue;i+gsn(c/8 :b nmally descends a bit and then rises. Explain.

A glass container may break if one par: mm 1zyxi(-4al)ufag t of it is heated or cooled more rapidly than axa-( z)mgau1lyi:m4f djacent parts. Explain.

The principal virtue of Pyrex glass is that its xs.qk9k-zg+w m,mjzs/.1e k7 y k*zsd coefficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance qkm m jkk s+/ d7e.z,xw1zy.k-s9z*gs of Pyrex.

Will a grandfather clcu)6sg m(uxyhm rz:oo3s 35 c,ock, 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 will cause its bottom952j a9o+vihnfgp t p+ and top to bulge so badly the can will not stand up. What has ha n+g9aopv9+t jhp52ifppened?

When a gas is rapidly compressed (say, by pushing down a piston), its 5n8.2 xa tt6g5f hi7y/ h)9,hyhci:dxkwlolytemperature increases. When a gas expands against a piston, it cools. Explain thesotyx:/ 9 ha 86 lnydihf.w,chg2tlk5i h7)x5y e changes in temperature using the kinetic theory, in particular noting what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force on an aluminum sphere submerged f*)n6jnq 2 icfak6 7r1;t td.nhv qu;nc o*5hgin water increase or decrease if the temperature is ifu5nc2ad6; t7gkt h 1 ifh.q;n )rqcv nn*6*joncreased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theory and the relati*d0qld hdy 0t5on between average kinetic energy an 0ddqh 5dty*l0d the absolute temperature.

Explain in words how Gay-Lujjy/r1* vz1. l8qj+5 xs(gldwcrv x4p ssac’s law follows from kinetic theory.

As you go higher in the Ea .k3g *p7aql417gh/dl epky4lj 9*fi * lvxzhbrth’s atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the mini( k cq(f o)shh)7emdwkjw .k+.lyt(8 kmum speed an object must have to leave the Earth and never return. The escape velocity for the Moon is about one-fifth what it is for the Eaksk d.qck(ewjhf.h8mtlw)k )(y (7 +orth due to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at room temperature. What can you infg6o*qjz 648g7y:fc1oy 6em magu p1toer about the molecular properties of one relative to the ot1goft8oa1og66mg* m zuyq 6p:j c ey74her?

Explain why a hot humid d/ .ihhg szt3a1ay is far more uncomfortable than a hot dry day at the same tempehashg.3 /tiz1 rature.

Is it possible to boil water at room tempef o17 a4bh*bqsrature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the a;5t:9g .a(ckequnyu xir temperature is the same but the humidity is different. Which is moreek.x;9u(qtnuc y5:ga dense, the dry air or the humid air at the same T? Explain.

Explain why it is da8 mkpvc)op+iuz+ ju8+)ccrxm n c74o3ngerous to open the radiator cap of an overheated automobile e8mxrc+ v)jico pmkoc+pu)z347 u+c8nngine.

Why does exhaled air appear as a l4mm umwd:,x +aittle white cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.u (0 i*e5w p*-:xolb(beb ylx9gmd(hp4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare to the npu. w,k6g5n 9b0y y*xc0/frrv:o nm mfumber in a silver ring of the same mass?p vruc 6:0mxn fywk*., 5yrofbn/ 90mg$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this on 4xa k4dzt8-v kzb3(frz-)blf ckss 2k,7ky w5the Celsius scale?-c,f z 28kls(kas3 4kvwk4bzb-kdtrzf)xy57   $^{\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 temp1- ua*x;dt(m ihyf 6vreratures recorded are 136 $^{\circ} $F in the Libyan desert and -129 $^{\circ} $F in Antarctica. What are these temperatures on the Celsius scale?high =    $^{\circ} $ C
low =    $^{\circ} $ C

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

  In an alcohol-in-glass thermometer, the alcohol column has le:o.luzxs q3(r ngth 11.82 cm at 0.0z(3xrsuqo: l. $^{\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 slajn 7 36.bk1qdngs. -nmfbir+jbs 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.y;kc: + 6arinj 13–29) is built of wrought iron approximately 300 m tall. Estimate how much its height ch j:ikc ry6;+ananges 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 akxbjv./)wrucj0cawf 4 81;gvre often used and the rivet is cooled (usually in dry ice) before it is placed in the hole. A steel rivet 1.871 cm in diameter is to be placed in a hole 1.869 cm ig .jc0v;bwrx8a4kw)1 cuvf/j n 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 att9tj / y0el2ac 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 bgf/v5 9mr/n -o7um 4 nsla5c o0k8qbnqe its change in volume if it is heated fromqr a8obu-fs 5/95onq0m vm/47knln cg 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filllq iqzonbr3 / cfh7n.2givu +f)bm6+ 6ed 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 ,cxs.v+c /hc9onhd /k 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 c(1q 2 x,z8 8qittopcdof 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 o9i cr;m6bjc6, narrow vessel so it can expand in essentially one direction only, show that the effective coe mj6c oc6r;ib9fficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the w(tk2ifur3o8 fv 6 fsba6+iky:p0 / dbdensity $\rho$ 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 coepg,5 4 (gqg6h,v ucrolfficient of linear expanl qg6r4vhpocg,g ,5u (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 isotropic n8bkdi 3qt90v 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 and keeps perfect time/q26xojelm fe )wv );q at 17 v/feoe6; q) wjqlm2) x$^{\circ} $ C. How much time is gained or lost in a year if the clock is kept at 25 $^{\circ} $ C? (Assume the frequency dependence on length for a simple pendulum applies.)$\approx$    min(Round to the nearest integer)

  (a) The tube of a mercury thermometer has an inside diameter of 0p4koh r8ex r4csgp owg4nict8;::3 * f.140 mm. The bulb has a volie3r4c: pr;c 8wto 8sgfgpk4hon:4x*ume 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 radiu7 -rkl4 x(dmjg -ktbxkt-0 7sts 0.41 m is rotating about its axlgd--xj7-kt t b sk(047txkrlme on 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*9pl65 nfpaea stress is required to keep it at this length if the temperature in fn6eaal*9 pp5creases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel vbe anh20heodg.6 9e62 vr2bc I-beam of cross-sectional area 0.041$m^2$ is rigidly connected to two vertical steel girders. If the beam was installed when the temperature was 30$^{\circ} $ C, what stress is developed in the beam when the temperature drops to -30 $^{\circ} $ C (b) Is the ultimate strength of the steel exceeded? (c) What stress is developed if the beam is concrete and has a cross-sectional area of 0.13$m^2$ Will it fracture?

  A barrel of diameter 134.122 cm ar 3hb -(/yncpg9mds l)t 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 followin.mujzf(zyuj56u+3v. jpf+ 8qu t r 0jng 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 what temperature on the Fahrenheit sygay:)2 ah7 xu(ok6zn cale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun are abou8n9mo4 mopp: iv:9bx dt 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 at4;*/ stgy jjxfmospheric pressure and a temperature of abxgy*;js/tj4 fout 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 oxygejnle)o.b nzm8fe/ z89n at STP using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of nitrogesfi d7kcixb0 l+*1 ;ipn ($N_2$) 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 1yi6vg- 1b.r,ar5zl jnpf8+6 f w:rh,osphp r*8.5 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 42ua wd(;a + u2etdexwgas is at 10.0$^{\circ} $C and a gauge pressure of 0.350 atm, (a) calculate the volume of the helium gas under these conditions.    $m^3$
(b) Calculate the temperature if the gas is compressed to precisely half the volume at a gauge pressure of 1.00 atm.    $^{\circ} $ C

  What is the pressure inside a 35.0-L contiil7t ,hpi,z+ gj8 th(cs. f2hainer holding 105.0 kg of argon gas at 38 hhi.7+ljh8tpgis(2,c ft,iz 5 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg z:q7pr c/nv.s- o 6ssd3*vo aqof $O_2$ 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 insi,b) ddjw2i* som q/. 1r4piv8d blsu6yde the balloonyilswi4or)1dbuqm,ps*2j b 8 d.dv/6, which makes it less dense than the air outside. Suppose the volume of a balloon is 1800 $m^3$ and the required lift is 2700 N (rough estimate of the weight of the equipment and passenger). Calculate the temperature of the air inside the balloon which will produce the required lift. Assume that the outside air temperature is 0 $^{\circ} $ C and that air is an ideal gas under these conditions. What factors limit the maximum altitude attainable by this method for a given load? (Neglect variables like wind.) $\approx$    $^{\circ} $ C(Round to the nearest integer)

  A tire is filled with air lm31ge7mj 8jq 3i-sbw at 15 $^{\circ} $ C to a gauge pressure of 220 kPa. If the tire reaches a temperature of 38 $^{\circ} $ C, what fraction of the original air must be removed if the original pressure of 220 kPa is to be maintained?    %

  If 61.5 L of oxygen at 18.0 enjr)v8xcq uz y0 xs2(9mo,+b$^{\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 level and 20.e: z1dl2 ,ivxry6)zpz0 $^{\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 /.ehn9(397es x b nrxhe $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? sp)t hwe; b0**h5iwoxHow many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of c;fup 4v n/jbt:h. l1dewqh 0,(a) moles,    $ \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.typ:p1dc2co2 en unh/( mv +k(1$ \times10^{ -2}m^3$ is filled with air at atmospheric pressure at 20 $^{\circ} $ C. The box is closed and heated to 180 $^{\circ} $ C. What is the net force on each side of the box?    N

  Estimate how many molecules of air are in each 2.0-L breath you inhi. b iuajej5juj;5uf+6 (9ommale that were also in the last breath Galileo took. [Hint: Assume the atmosphere is about 10 km high and of constant densi9 afbu;jij(6u5iejm5 jm.u+o ty.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of newc:0kvy 7*lma uh82n v0 q6san oxygen molecule at STP?mya2 e hk6nnc*:l8u vws007 qv    $ \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 helioe2dn k3hv7gmy v,/q/um atoms near the surface of the Sun at a temperature of about,ne d 2hykqmo73/ vgv/ 6000 K.    m/s

  By what factor will the rms speed of gas molecules injai (h-yj2 0ogcrease if the temperature is injyj2(i-0aogh creased 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, )kme a-.hip8s 4, 6, k. shi8ea)-mp0, 4, 1, 8, 5, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at t9 dqzqeaxc a1(2u p0)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 consumxgi;0 nw;8j tant, by what factorm wg8nj;;iu0x does $v_{rms}$ change?   

Show that the rms speed of molecules i3mui b vt9xf :p8lewjjt1(.i :d k:/van 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,.vpb1xrt1n)7 hl ;3xnwwul (m the ratio of their rms speeds is equal to the inverse ratio of the square roots of their molecular un;l)h xwxm1t. ( w1rv73lbnpmasses.

  What is the rms speed of nitrog yc)// bqhzm)gen molecules contained in an 8.5$-m^3$ volume at 2.1 atm if the total amount of nitrogen is 1300 mol?    m/s

  Calculate (a) the rms speed of an oxyge q1pjal5;y* g b- x.ixhm6ew lfdp9n+8n molecule at 0 $^{\circ} $ C    m/s
(b) determine how many times per second it would move back and forth across a 7.0-m-long room on the average, assuming it made very few collisions with other molecules.    round trips per sec

  What is the average distance between nitrogen molecules ab sqtx.3sra+1 1z-eeqt STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular mass is 89 gzq2 e2 svi0bfw3 y 1v*qjmi69u in a living cell v12y6j 0esiizq*2b 3mfwqg9 v 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(2i -dseh 3 ke6zvg4fy 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, u*r, bla(z lm.$^{235}$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 cailvx a3qa)w:0 n $CO_2$ 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 pressu c/nq/b, jqq,ure is 0.01 atm and the temperature is (a)q jq/,/cq,nbu 90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity is 50% on a day when the lzeo2( pv9wl b:h.yx+temperature 2z :ex9hpwv+y(l bo.lis 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place wheregw l/*)u)* mc 4 cje9 r8ejbjab:p7ant water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is 0.72 )vtd0dg no : zlv++u),s/osxdatm, estimate the temperature at which water s:sl xz)/d+dg,o t+u)0ndvovboils. $\approx$ =    $^{\circ} $ C

  What is the temperature on+nz-j0 (q 9w.6yzetp:g s sqop a day when the partial pressure of water is 530 Pa and the relative humidity iseo q.t:9g (zjs6 nyzspw+-pq0 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure o7v ;dhpf:2ypd4 1j1 l/c gctprf water on a day when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pvllv1wp n8r/; ressure cooker if the water is boiling at a temperature of 120p1nvlv8 /w ;rl $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room ofg ydof95ucp ykt08-- t 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 p wnc+bc;e1hu)oint 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 Tabl.dadr4a idj )9e 13–4) to diffuse a disdr 9)4a aijdd.tance 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 rp:+l3*; )a dhhvytwk tubes called tyawh;rv)3p:+h k*l d tracheae. An average trachea is about 2 mm long and has cross-sectional area of $ 2\times10^{-9 } m^2$ Assuming the concentration of oxygen inside is half what it is outside in the atmosphere,
(a) show that the concentration of oxygen in the air (assume 21% is oxygen) at 20$^{\circ} $ C is about 8.7 mol/$m^3$ then $\approx$    mol/$m^3$(Round to one decimal places)
(b) calculate the diffusion rate J,    $ \times10^{-11 }$ mol/s
(c) estimate the average time for a molecule to diffuse in. Assume the diffusion constant is $ 1\times10^{-5 } m^2/s$    s

  A precise steel tape measure has been canwoz3b h,e s*di38p akc6,,a nlibrated 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 beenos0x*xv73exz 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 ro bj:y)4:+egk ; nsvsld5hwlzhb0n80 som temperature. How much error will be made in a recipe calling for 300 mL of cool water, if the water and the cup arsnd5 ye0wvgk +h)n b 4l0s hz;::jbl8se 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 initiallqpe;9z- e 6qyxiz6c lbd l8c *8kxc0.ay 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of the original gas rem;8q c.k6y ibx-llc6 adeq0zx8z* p9 ecains in the cylinder?   

  Estimate the number of air molecules in a room of length 6.5 m, width :1bbg 3cr2(u) u skdqv3.1 m, and height 2.5 m. Assume the temperatu 1gv bc(s32ukrq: u)bdre is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter inc * :ksn.qaj a;0fv9 ergx)5ws 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 ::wr-vl)pedyf1 v g b/techniques is abov)de:py-l bf v/r1:wgut $10^{-12} N/m^2$ 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 Lvu;o 6k dvw-6e when 10 m below the surface, to what volume would his lungs expand if he quickly rose to tho 6-uw;vkved6e surface? Is this advisable?    L

  A space vehicle returning from t rj1fl avp7d78he Moon enters Earth’s atmosphere at a speed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this speed correspond to what temperature? (Because of this high temperature, the nose of a space vehicle must be made of special materials; indeed, p177d pj8l afvrart of it does vaporize, and this is seen as a bright blaze upon reentry.)    K

  The temperature of an ideal mg 6j)p2 6mlauguhh,*r 1-hxv eb2 p9ggas 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 7gy . (jh+hn8 dggqau5970m$^2$ (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 atq c5ovx-fri0u ,--/p9vkqp98 rz o eap the surface of the Earth, estimate the total number or pfqu9ax-8-5zqcp p0ioevr /o v-9,kf air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitroz+x60 n+c:sdia.in u)exf pt 10 c-nplgen 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 used9-6d t 9iwoxkp in a hospital has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured attikwo99p- xd6 atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liquid mercua ep12-k93*vxp wo8zd b9soilx 3+bgj ry 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 pzf o+yi3rp7- at 0$^{\circ} $C is 0.68$ \times10^{3 }kg/m^3$ What is the density on a hot day, when the temperature is 38$^{\circ} $C?    kg/$m^3$
What is the percentage change?    %

  If a steel band were to fit snugly around t9wa,yq4azzy(yl8 w6j* z mb7ehe 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 glass jarbaerex *3.rb4auyk03b 1ls s r9 ii,.a 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 the 18 . l/wejjkkh+u;rjr/6 $^{th}$ 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 cha56+ bqtejj0))mb fxfvrged, 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 thei cs-r*; gjhc)bcws;4 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 tennis balls thrown yp athsr8w3a1h 5(a,il -c ufa49)jd nvertically upward at it. How many tennis b- 9jhi1u53raap(l h yf,8csdnta)aw 4alls 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 3.00-cm-diameter (spherical) bubble of ab15,d+ylbzoqaf l 2)mir from 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 the1l+b yfz 2,d5qmo )bal bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure- miig7j3(p dt in the air on the following two days: -m7 (tiig3jd p
(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 densia)1nxctec /y2 9nw wepoln993 ty of iron at STP, and when it is a solid decnx9lt39)wcw pn91e/ 2 aoeny ep in the Earth where the temperature is 2000$^{\circ} $C and under 5000 atm of pressure. Assume the bulk modulus (90$\times 10^9N/m^2$) and the coefficient of volume expansion do not vary with temperature and are the same as at STP.    %  ----待选择----decreaseincrease 

(a) Use the ideal gas law to show that, for an ideal gas at constanj;h44r.;k7x 6hda(mqsxi mxwt pressure, the coefficient of volume expansion 7kmj ;r ma(x;d4wx4qsh .xh6iis 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 cellarsd 4)gg11mb3pdqd(wvw9x kwv1 11zru x to prevent rot and mildew. If411duk9(v)x 1w3gp1g1mvbxddq rwwz 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