Which has more atoms: 1 kg of iron or 1 kg of aluminum? Se m c90xxe(x,coe the periodic table or cm0o9 ecx,( xxAppendix B.

Name several properties of materials that co:mu6j fci srd*/ yqhp a)r z*2(om:rl(uld be exploited to make a thermometerduh( q* 2 a6*f(l/rymiomps)j::z rcr.

Which is larger, 1 C m5zs k:i xgkypmb ogr4,58 e5* x/bq8f$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system+hlx 9 . zo80r2upswq2jkde (u B, but B is not in thermal equilibrium with system C, wha2(pudxe 0os 2k .zuq jr+lh89wt can you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to a strip of iyrs6gw )6zrvcrb6:2 wron. When heated, the strip will bend. Which metal will be )bc66zww2 ry vr: 6gsron the outside of the curve? [Hint: See Table 13–1.] Why?

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

The units for the coefficient of linear exp8kme .q-. y3+kdqknmy3g2h pfansion $\alpha$ 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,b e6oijglz :1oiojro 9 q5(d0;rq,mt a furnace (or other heating or cooling system). The bimetallic stritd,1r m9o ;:(r6elqo,z jio0qo5 gibjp consists of two strips of different metals bonded together. The electric switch is a glass vessel containing liquid mercury that conducts electricity when it can flow to touch both contact wires. Explain how this device controls the furnace and how it can be set at different temperatures.

Long steam pipes that are fixed at the ends often have a section rxegrm 0*6.y vin the shape of axr 0rm.vye6g* U. Why?

A flat, uniform cylinder of lead fl x3zd-h hfg 952vugjfcc0(+y wp*z ba*ovr0z1oats in mercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass tip-+ ji9tkg/nk-i: awhermometer is first placed in a hot tub of water, the mercury initially descends a bit pai -9ti- g:j+nik wk/and then rises. Explain.

A glass container may break if one pae 4l g4d8r8cmhwa.lckp 0;z2prt of it is heated or cooled more rapidly than 0 pg8kc8.mpez; hdlrw42alc 4adjacent parts. Explain.

The principal virtue of Pyrex glass is that its coefficient of line1 lbm ljnq8fs(419oz6ybfyaih1/ er)ar expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pz(fj1lao bylby/)48 in91f6qsr1hme yrex.

Will a grandfather clock, accurax4d h42)vzbam ig0+ mate at 20 $^{\circ} $ C, run fast or slow on a hot day (30 $^{\circ} $ C)? Explain. The clock uses a pendulum supported on a long, thin brass rod.

Freezing a can of soda will cause its bottom and top to bulge so bv a aumzxl rbmx9l7fe69q r, 6z93ck67adly the can will not stand up. What has happenecalu v,9mzk9ql6 xm 7b3fea9r7 xrz66 d?

When a gas is rapidly compressed (say, by pushingks(v n21veq(d down a piston), its temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperat(enq2k sd(v1vure 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 in wddxc+7t0kj/03r.9 rq1b zzw6tmf hyj ater increase or decrease if the temperature is increased from 216xf3yhqkdjjwt0z zmb9 d t0r.c7r+ /0 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theory and the relationofh(ycmms1 /1f (nkmffq6f5o q3t6+v between ave k(3yohqffv6( f ctf61sqfn1 5mmo/ m+rage kinetic energy and the absolute temperature.

Explain in words how Gay-Lussac’s law,()rx.8qgr4d 5cp: :tpw8s c1nhkqlx .sk yxc follows from kinetic theory.

As you go higher in them7 p9yac0ss(kf zt;p) Earth’s atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed an og/ nalm 8v2c v9us.dq/bject must have to leave the Earth and never return. The escape velocity for the Moon is about one-fifth what it is for the Earth due to the Movd2qmug. // n sc8lav9on’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly tl fu(n:)y sgprxy 95o4han water at room temperature. What can you infer about the molecular properties of one relative to puny(:9gry)4x l 5softhe other?

Explain why a hot humid day is far more uncomfortable thandcb:8 cl -jpq/ ;3+ma0ugcxm yhu:do * z6w5iz a hot dry day at the same:g:8dylwzcuiaodjc m3*bcux6/ m+-q5 0 z;hp temperature.

Is it possible to bom+r f y maf46m-oqp1*b0z mb/eil water at room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the humidituvrh/99 o6uftqxgc956 t f:idy is different. Which is more dense, the dry air or thcfd/qt g 5x:u fr9o utv699ih6e humid air at the same T? Explain.

Explain why it is dangerous to*qmzw2h se+9 j open the radiator cap of an overheated automobile + 2j9ez*shw mqengine.

Why does exhaled air appear as a little white cloud in the winter (Fi08(y bu:xxmu lg. 13–28)?

  How many atoms are there in a 3.4wu*3yt7cyg +l -gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare to the number in2jaktbb 67 fp3 a silver ring23b7 f6kjtabp of the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taj ;mvd /eh 56ul1ij4laken to be 68°F. What is this on the Celsius scale? ma6 lli 4jd/v1heu5j;   $^{\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 recor y6hs8 -:j2 yzllem;uojkhh3+ ded 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 cozi2zu/ m)fivu77 /-mca9ycx olumn has length 11.82 cm at 0.0 u9a zmf-y/m ivc/u7xzoci7 2)$^{\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 1a8.xy fpid1: d2 m long (20 $^{\circ} $ C). How wide should the expansion cracks between the slabs be (at 20 $^{\circ} $ C) to prevent buckling if the range of temperature is -30 $^{\circ} $ C to +50 $^{\circ} $ C?    m

  Super Inva$^{TM}$, an alloy of iron and nickel, is a strong material with a very low coefficient of linear expansion [0.2$ \times10^{ -6}$(C?)$^{-1}$]
A 2.0-m-long tabletop made of this alloy is used for sensitive laser measurements where extremely high tolerances are required. How much will this table expand along its length if the temperature increases 5.0 $^{\circ} $ C? Compare to tabletops made of steel.   $ \times10^{-6 }$ m    $ \times10^{-4 }$ m

  The Eiffel Tower (Fig. 13–29) is built of wrought iron approximat82t.grysgll + s9 hny6ely 300 m tall. Estimate how much its height changes between July (average temperature of 25°C) and January (aveyhgl g+ l8nrt.s9s 26yrage 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 fits1vw0,9kz gu06 9txo f1 qboddspx9u/5zro)i, rivets that are larger than the rivet hole are often used and the wuoxo kuf,p90zx6 g dt0dr)/sv s bz1 1o95qi9rivet is cooled (usually in dry ice) before it is placed in the hole. A steel rivet 1.871 cm in diameter is to be placed in a hole 1.869 cm in diameter at 20 $^{\circ} $ C. To what temperature must the rivet be cooled if it is to fit in the hole?    $^{\circ} $ C

  The density of water gw)a7 c3b( xrdat 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 diameterr+ gewf-k-lp 0jhl5d/. What will be its change in volume if it is heated from 30kp/-lwe + f5-0jglh dr $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim86smz +hq8s2r1ohd / htnq+r o 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 waterd1ujb7: wv/ z5wo, lwfx9y0tz 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 x, py 6m.5thg,gly5h3v td;sdof 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 s6/)p pu83isixts s q-io it can expand in essentially one direction only, 6usisii)-8/ts3 ppxq show that the effective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the changyr.e ,x(f jm4qx9kd( ue in the density $\rho$ of a substance, when the temperature changes by $\Delta$T is given by $\rho$ = -$\beta$$\rho$$\Delta$T
(b) What is the fractional change in density of a lead sphere whose temperature decreases from 25 $^{\circ} $ C to -40 $^{\circ} $ C？

A uniform rectangular plate of length l and width w has coefficienthong c o y/7:slzk/betlm19a5w (+0j o of linear expam/k yl 1+0g7a tolhbco j/(9own: 5zesnsion $\alpha$ 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 sojg 9y my,/od;rqhp :q 03s9dvzlid, $\beta$ = 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 clodgd;k+i6gq*k otw/ r jax9 - 9p8fx4wnck is made of brass and keeps perfect time at 1/+ia6 k j;w9rq-g4owpg9kfdn*8xtd x 7 $^{\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 in x0 fdyu( yfcmd,ojh(po26 )6 wo*ymx1side diameter of 0.140 mm. The bulb has a volume of 0,6mx 0y6d)xu1 ym * dowofy2jhfco (p(.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 alumi .2h*i af9ihb8uxvyld5h *.e fnum cylindrical wheel of radius 0.41 m is rotating about its axle on frictionless bearings eb89. va*5hihlh2dixy. uf * fwith 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 des ik: o3dve 84k.5wbribired length when at 15°C. How much stress is required to keib: kwbd84 5kr3ve.o iep it at this length if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-secl:wcp 1/ d),yvu vv7nftional 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.mb96dlr 2crj9m2+ us c122 cm at 20$^{\circ} $ C is to be enclosed by an iron band. The circular band has an inside diameter of 134.110 cm at 20$^{\circ} $ C. It is 7.4 cm wide and 0.65 cm thick.
(a) To what temperature must the band be heated so that it will fit over the barrel? $\approx$   $^{\circ} $ C(Round to the nearest integer)
(b) What will be the tension in the band when it cools to 20$^{\circ} $ C?    N

  What are the following temperatures on the Kelvin scale-qv )15 s2pwc5lhy ytx:
(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 th8w)z 8dfe0/ z/cr6 gtgww/ zzoe Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the inteyay kgajr/+il87v, 0i rior of the Earth and Sun are about 4000$^{\circ} $ C and $ \times10^{6 }$ $^{\circ} $ C respectively.
(a) What are these temperatures in kelvins?    K    $ \times10^{ 6}$K
(b) What percent error is made in each case if a person forgets to change $^{\circ} $ C to K? $\approx$    %(Round to the nearest integer) $\approx$    %(Round to three decimal places)

  If 3 $m^2$ of a gas initially at STP is placed under a pressure of 3.20 atm, the temperature of the gas rises to 38.0$^{\circ} $ C. What is the volume?    $m^3$

  In an internal combustion engine, air at atmospheric pressurn :x1/* oxvvgshj 6cf4e and a temperature of about v 1f6jxnxc:g /vo4*sh20$^{\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 oxyge ) qo2v/d6ynw;s.tz;+fh wn zon at STP using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of nitrogen l8fgg804z abp ($N_2$) 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 of nitrogen ( oh 1y4(ule6r*jnclb5$N_2$)
(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 heliumon*ez7ze c loe- h*k3, gas 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 container holding 105.0 kg of argon gas at 4 ;huf;yfv ,g1f6xg+zh vsby9385 K?+4yfzg xs 1f6u,gbvf h hy9v;;   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg of 03 lq 0 6xkzymeia1/gp$O_2$ 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 o 9kozxgl.q(af c*x:+0 nw ok4by heating the air inside the balloon, w *fzoawo :4.ck0 nkq(+xgo9 xlhich 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 at9 igk/2k s )gz;7eqpka 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 *g jvmv18kxr 3$^{\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 lekhvs2s(v ku yi x irw7+b9+8:zvel 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 wf*,t f:dsfl:ecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are theq. nrfih.3(p bre in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) molefzgs xz-e;* m,,a cd-ts,    $ \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 hu.6/ns c5g hfjm8yw; 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 breath you inhale io9*mc8 b:d/21*iuona s sxwbthat were also in the last breath Galileo took. [Hint: Assume the atmosphere is about 10 km high and do /iuc bb*a:wi*ons m9x812sof constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of an oxygen molgh2 u ne oy476htroy+xr1og9 b/to79 fecule at STttoxb97heyg 1nf h 7o 4or/uoyrg62+9P?    $ \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 s );-ad -vwenb7b e fo46eslkr w*qqv)8urface of the Sun at a temperatuvow7-f8b4 v qq ) eklnb)a-*se;6werdre of about 6000 K.    m/s

  By what factor will the rms speed of gas molecules increase iecgr4ef ,k5y62lod4le e d3s) f the temperature is increase)2l 6see 4,r5f 4y c3oelegdkdd 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,2y o-cb-h *m-hluv1p9ukwslzb +x .-z given in units of km/s: 6, 2, 4, 6, b+u2oy-pk-bz -- l*xslvuzw 1m9h hc. 0, 4, 1, 8, 5, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at7rnz xfr/j b)dinl 4/l2)gs0y30n g nn 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 constanta ohv4gsy.p1+ , by what factor y+hg svp.1oa4 does $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is given by z2rs+ w+ *xtkhtw16o1tb s8is $v_{rms}$ = $\sqrt{3P\\rho}$ where P is the pressure in the gas, and $\rho$ is the gas density.

Show that for a mixture of two gases at the same temperature, the ratio of th7. 6tp;u;c0xg a1h xqv8yyniceir rms s.;i y7x6yug0 c81x;pt ahvqncpeeds is equal to the inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen molecules contained in an p/twqs3/gemm :mve36 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 +,y p1v)qwr0mzkihy79pfom2ht.cm / of an oxygen molecule at 0 $^{\circ} $ C    m/s
(b) determine how many times per second it would move back and forth across a 7.0-m-long room on the average, assuming it made very few collisions with other molecules.    round trips per sec

  What is the average distance between nitrogend skhq9g- ubym4 5t-j4uazgi*p, 1hrl ;;:sfg molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular mass is 89 kvfcfx)j :4xlm s*(4 ju in a living cex *sl 4xm(ckjjf )v:f4ll 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 writg5i 0c.+d/8yp xzeg.tw8xp ,ewair(d ten 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 u 5(h9o 8ja e x+++ewopknw7uzeranium, $^{235}$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 whato1bf vy/z7og)92 r kpv 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 * es 5s93amhk77bd svng5k+ avthe pressure is 0.01 atm and the temperature is (a) aabs973v5kdgs nsm kh+ve* 7590 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if t58mw3i ,jtn;qdzy oc4he humidity is 50% on a day when the temperatuzt8y5 3;j4dcm,qnowire is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water boilsrs8 c03.yxg *iiix *jx at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mounteih1iqb 7u4 2pains is 0.72 atm, estimate the temperature at which water bo uh 472ep1bqiiils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressursg k5:ilw4c -ve of water is 530 Pa and the relative humidity is: 4gilw-5vksc 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day whenisqdp.rvv;jx ksnfp7 69u 4c /+1p6kc the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure coo m1 unk q+5lgb+enn9s0ker if the water is boiling at a tempera++s0le qg mkn51nun9bture 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 volt2i0) cqs8:oz1jn7 do (gipcgume 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 dew1hyh n90tknnx75: 1)rcaiqmfs +mx0 h point 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 glyciy50 yadx8g(8fh.zf bkne molecule (see Table 13–4) to diffuse a distanc (ga fyb5k.yzf 08h8xde 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 5 aswvpm*aq +p7:ghe;4qz 1ducalled tracheae. An average trachea is abo:s5p;ahdvawep*71 quq z4+g m ut 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 cad4t qkmcx4 :tlww1e)z 2(at r*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 measu 2 +x4yw5asscm1)dxju re 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 te q6lmwkrgk,m5)25 any1.jg rcmperature. How much error will be made in a recipe calling for 300 mL jqm w2. cl55g1n rr,akmg y)6kof 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 initially 28 atm. After many bo.h7 mq.5;t2v*gg 9rnlc eotgc.g q-zalloons have been blown up, the gauge pressure has dng9t * g.gcmeoo.lqc7-vq z.gt25 ; rhecreased to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air moleculf uw/4sp3h (ames in a room of length 6.5 m, width 3.1 m, and height 2.5 m. As/ 4fpsahm(w3 usume the temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the dense-r3g-wzm / roity of matter is about one atom per $cm^3$ mainly hydrogen atoms, and the temperature is about 2.7 K. Calculate the rms speed of these hydrogen atoms, and the pressure (in atmospheres).$v_{rms}$ =    m/s    $ \times10^{-22 }$ atm

  The lowest pressure attainable using the best available vacu+yoi bj2+y-m0 , hxlmockit46um techniques is aboy,2xm yhjo-oii+mt6l 0k +b 4cut $10^{-12} N/m^2$ 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.o1xnp77v*ilo bv6n h +5 L when 10 m below the surface, to what volume *p hil+n1o6nv7xb 7 ovwould his lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moobcb q v j:bqh(y*vo. l0ok2.n+yhdi:5n 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*yqon ov5+b. 2.:: jkiv0bhbld(yc qh, the nose of a space vehicle must be made of special materials; indeed, part of it does vaporize, and this is seen as a bright blaze upon reentry.)    K

  The temperature of an ideal gas is increased from i;j ra, h(p/e*1qxvl a110$^{\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 770(ytp)*1gm6f.e d;hrv a6x hv dm$^2$ (a) What is the total mass of air inside the house at 20$^{\circ} $C?    kg
(b) If the temperature drops to -10$^{\circ} $C what mass of air enters or leaves the house?    kg

  From the known value of atmospheric pressure at the surface of the Eartdny 0;.mp5bt0afj)y/azs gz/h, estimate the total number of air molecules in the Earth’s atm.y0ybj5 0zz p fmds)n;t/ag/aosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrw epj8 h9,cjk.ogen 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: z0 kif0agpse (o::yo oxygen used in a hospital has gauge pressure = 2000 psi (13,800 kPa) and z :gkao0(ps 0y foi:e: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 liqui3 hr5 :b) b+rzehq;najd 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 gasoline vb ;f atvq b+1.2e)uxpl41 trbat 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 werevcqdj4ugocnu6j5a / - .7ng-z 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;kk(fl 4;iy kc1ogl1 a a glass jar at 20$^{\circ} $C. To help open the jar, it can be placed into a bath of hot water. After this treatment, the temperatures of the lid and the jar are both 60$^{\circ} $C. The inside diameter of the lid is 8.0 cm at 20$^{\circ} $C. Find the size of the gap (difference in radius) that develops by this procedure.    cm

  The first length standard, adopted +d.jce 6 jewjnl5,e-b / :,fq8il rqtzin 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 chare o.063b cxtkiged, 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 the Earth i2z*w ri5;-+8)oqv wmmh hhsqss $ 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 susck*hfbq71k0 lu/ax+p 6inai) pended against gravity by tennis balls thrown vertically upward at it. How many tennis balls per second must rebound from the lid elastically, assuming they have a mass ulkf6iph1xiaq / ) anc+bk*70of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a xz36/q;j hesv3yy m k1yb3:gk3.00-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 air behaves as a perfect gas. How large is the bubble when it reac/yyk hs1q y3bex3;zm 3jk:gv 6hes the surface?    cm

  Calculate the total water vapor pressure in grywqsmi4j.hi4r*4) /,4zavrp , oyethe air on the following two days: 4hpi mr eqvojrr,)4ygay.4sz /i4,w*
(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 whe1f11-rtny lb*+or2w,uvqno un it is a solid deep in the Earth where the temperature isv*wbr y1-nofu12 ,oun +l 1qtr 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 a,2 kuwpu zc vkk)qo*7.t constant pressure, the coefficient of vol*cw.ukkpuv2) , oq zk7ume expansion 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 cel 7np46 p7 8rtxnuwtrhoo 1/.dtlars to prevent rot and mildew. If the cellar in a house (kept at 204ohtux. 7n1pt /d rn7t6powr8$^{\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