Which has more atoms: 1 kg ofnhw4s ra0 -j);6(sgfom b6zq ta04 ted iron or 1 kg of aluminum? See the periodic table or Appendix 6rofsh- qz e6ds0ja;w)g 4bt0mna4 t(B.

Name several properties of mate3fs+dzt57q- oavt d d/rials that could be exploited to make a thermometer/ dotdqzfs-+v3 td75a.

Which is larger, 1 Ci*e s- y/dq/wj $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilrh0nie4qaz8j 4b j) j6ibrium with system B, but B is not in thermal equilibrium with system C, what can you say about the t4narej0h jq4i8jz) b6 emperatures of A, B, and C?

A flat bimetallic strip consists ofcjc7 30q5+s e on sg)pnq4q(me aluminum riveted to a strip of iron. When heated, the strip will bend. Which metal will be on the outside of the curve? [Hint: See Tacn )+0oqssge cp mjqq4n 3e75(ble 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 coefficientyy8/iz.tx4ua csuc 59 of linear expansion $\alpha$ are $(C?)^{-1}$ and there is no mention of a length unit such as meters. Would the expansion coefficient change if we used feet or millimeters instead of meters? Explain.

Figure 13–27 shows a diagram of a simple thermosv gcl,:;/.et*nwvh d( de5hhoa8i4 kx3kc0 bptat 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 contac/vgkv4x 0eick 5 (bow *,cpl h3ae;:nh t.8hddt wires. Explain how this device controls the furnace and how it can be set at different temperatures.

Long steam pipes that are fixed at thdqs)bi6 kq;vr0(ho* qe ends often have a section in the shape of a k* qqb0s)or(; hv6dq iU. Why?

A flat, uniform cylinder of lead floats in mercury at 08(at9dc 7cqlt $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometer is first placed i :-ijd+dr:l vf w,; q4gfi1naxn a hot tub of water, the mercury initially descends a bit and then rises. Explainn fv -il;j:qx d1+ i:far4dgw,.

A glass container may break if r*y5, 5cb xdxr2hhzm 7one part of it is heated or cooled more rapidly than adjacent pa5 hr,5hy* 27czxrxd mbrts. Explain.

The principal virtue of mn1y/wc-iy m4Pyrex glass is that its coefficient of linear expansion is much smaller than that for ordinary glass (Table/4m ym-in1cy w 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurax op x gjo2k3-/d6(caate 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 badlyrmp5.crpic(k8 ,he .e the can will not stand up. What h pmek8.(hicr,e p5.c ras happened?

When a gas is rapidly compressed (say, by pushing down a piston), its tey,0 e rv1ueyb4mperature increases. When a gas expands against a piston, it cools. Explain these cheuye 40vy1, branges 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 aluminufccv md(o-:b)arpe ka2: ,.nm m sphere submerged in water increase or decrease i(o2m f bv)::apacrc.,d mekn-f the temperature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s mujvwvo2 duj56d)- 1:f fwt- plaw follows from kinetic theory and the relation between average kinetic enwv -6-u 5jdt w12fvo)u d:jpmfergy and the absolute temperature.

Explain in words how Gay-Lussac’s law follows from kinlalo0az*q-m49r+jgjpg 3fj i b5f l-(etic theory.

As you go higher in thfd 1 *3kph*lwae 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 object must havnje:0w/c wxt7f z61bee to leave the Earth and never return. The escjz0 e: f7btw 1wcx6n/eape velocity for the Moon is about one-fifth what it is for the Earth due to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at room tecf15d g8whll5xc c 988ty0 fplotvs3*mperature. What can you infer about the molecular properties of one relative to the othercoy1s8f w l*0t 3cv p5llt9 88hg5dfcx?

Explain why a hot humid day is far more uncom,2m o),0 tt09r59 c)llofprnp pvsvzsf8b 9zjfortable than a hot dry day at the same temzo9,b58 sf f9o9tr p0pl ,zns0)rtclp v vj2)mperature.

Is it possible to boil water at room temperatwh+rlrg4 (1nd9cxioa,9,gr ture (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the samxen*n /va, u:/:h3kaztzu 5sme but the humidity is different. Which is more dense, the dry air or the hum:3,xus:a*hnnt u 5zv km/z/eaid air at the same T? Explain.

Explain why it is dangerous tf.v*fl7herz 3vyq4kg2 vo ,7 bo open the radiator cap of an overheated automobile engh.o4vvvql b7ke37yzf f,g* r2 ine.

Why does exhaled air appear as a little white cloud in the winter (f83sdt3d 4n2:fi xl ksFig. 13–28)?

  How many atoms are there in a 3.4-gram copper nok*asbbjbb +/2un 11 glpp, i j/(nx/penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ringf:b3i x gi8b lff/5z7g compare to the number in a silver ring of the sgbff /87fiilxz:5 3gbame mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. Whagi z9mzi;n+wb9r n/ 3f:u1esrt is this on the Celsius scale?+ns9;91b e nru3 rmfzii z/:gw   $^{\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(6qrlnu-: v6c sdwt2vx ly xk645de+ + :kqrbz lowest temperatures recorded are 136 $^{\circ} $F in the Libyan desert and -129 $^{\circ} $F in Antarctica. What are these temperatures on the Celsius scale?high =    $^{\circ} $ C
low =    $^{\circ} $ C

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

  In an alcohol-in-glass thermometer, the alcohol l vg:193x6o7d +zm9qpa bpk tte3mjz3column has length 11.82 cm at 0.0 mkz3bm1zx9 tq3g+v7 jtae3 :d96lppo $^{\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 (20 g9i/5 jo6c u)9knc /uvk c v)cknsac11$^{\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 bui.elz 0hg +o1qglt of wrought iron approximately 300 m tall. Estimate how much itsg q zolh.eg1+0 height changes between July (average temperature of 25°C) and January (average temperature of 2 $^{\circ} $ C). Ignore the angles of the iron beams, and treat the tower as a vertical beam.    m

  To make a secure fitw ;4 n:2)bt lhgqxw x hf(ez)(-rek:ch *jtz/g, rivets that are larger than the rivet hole are 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 - ; qb xc(z )4nekhet ::h(g)/fl2*xjw ghwzrtplaced in a hole 1.869 cm in diameter at 20 $^{\circ} $ C. To what temperature must the rivet be cooled if it is to fit in the hole?    $^{\circ} $ C

  The density of water at m 2ugk/,wh eckj yq9 )01kfa*m4 $^{\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. W87qci5b;q s,dzq:jshmf)z, m hat will be its change in volume if it is heated from hqfzzc8bq:s; m,,7dis jqm5 ) 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350.0 mL of water 8f y,qp zz)swml/h0 5vat 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 55.5m1z 8o:ih8 5 a.awrbcr0 mL of water at 20 $^{\circ} $ C completely fills a container to the brim. When the container and the water are heated to 60 $^{\circ} $ C, 0.35 g of water is lost. (a) What is the coefficient of volume expansion of the container?    $ \times10^{-5 }$ /$C^0$(b) What is the most likely material of the container? The density of water at 60°C is 0.98324g/ml.

  (a) A brass plug is to zq4yrs : *ri /; 0mtxka-nye6xbe placed in a ring made of iron. At 20 $^{\circ} $ C, the diameter of the plug is 8.753 cm and that of the inside of the ring is 8.743 cm. They must both be brought to what common temperature in order to fit?    $^{\circ} $ C
(b) What if the plug were iron and the ring brass?    $^{\circ} $ C

If a fluid is contained in a long, narro afov u+b q8tr(b35j.tz *3dsdw vessel so it can expand in essentially one direction only, show that the effective cobrt85s3 (uqdbdt3za+o*.jfv efficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the chlu:myugrn k y/bm 8m44yk.i+)ange 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 coefficieney/09dgvttclc)j9;e :: fdw b)uky(ot of linear ex yj;uw cf9yt) cv9 /d:ke )beog:d(lt0pansion $\alpha$ 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 isotro xt2+oi5lztrg:,*dq brb)e.lhp 2 s5gpic 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 grandfatheb6,u86 mgk)qt4 lspbnr clock is made of brass and keeps perfect time at 17,s6m) 6n4u bglbpkq8 t $^{\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 hr.;v twq f/l02ed5e kwas an inside diameter of 0.140 mm. The bulb has a volume d0 / r2.twkwvqe5;lfeof 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 rawcs1ukes0 yoxq5 cx(342p,xe dius 0.41 m is rotating about its axle on c xqy (xkse034x5 c,wpe12suo 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 gun/:sli3*0nxxmb ;1v ;log othe desired length when at 15°C. How much stress is required to keep it at this length if the temperature incre/g:l; 3sgbix uoxon *lnv0m ;1ases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal stec1q4 y6ps 1onvel 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+ 2ob,d velxj6 134.122 cm at 20$^{\circ} $ C is to be enclosed by an iron band. The circular band has an inside diameter of 134.110 cm at 20$^{\circ} $ C. It is 7.4 cm wide and 0.65 cm thick.
(a) To what temperature must the band be heated so that it will fit over the barrel? $\approx$   $^{\circ} $ C(Round to the nearest integer)
(b) What will be the tension in the band when it cools to 20$^{\circ} $ C?    N

  What are the following temperatures on the Kelvin : xyksd */rct4 drba4*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 l9pqeo8qclpsvb*y +i-d2*bt9a (vtz n.xw (* on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun are abouplirr08b.l61 czuia .y yea ,9t 4000$^{\circ} $ C and $ \times10^{6 }$ $^{\circ} $ C respectively.
(a) What are these temperatures in kelvins?    K    $ \times10^{ 6}$K
(b) What percent error is made in each case if a person forgets to change $^{\circ} $ C to K? $\approx$    %(Round to the nearest integer) $\approx$    %(Round to three decimal places)

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

  In an internal combustion engine, air at atmospheric pressure and a temperaturb c570 yn+aahye of a0c h5+yb ya7anbout 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 1.zgv wf)s rr jdhm2kx63 (c,bw*i,vg the ideal gas law.    kg/$m^3$

  A storage tank containstm4 h0c8 e t2r:/ogciue2 q5bf 21.6 kg 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 of ni7vjoo-7;ov sytrogen ($N_2$)
(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 iso 8mb6,n8 vxw)po a(9 huua6ng 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 nu9bj;a7a py g)51pmn v8vv -scontainer holding 105.0 kg of argon gas at 38av1av8un;p-5j97gyv smn )b p5 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kgd/g7-y6pz / i*znu wvhs:- uoq 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 g4 mins07fqk 8 s4*i-gk:yqim inside the balloon, which makes it less dense than the air outsidk:q- k7gf in s8ysgimim44 *q0e. 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 a,gzxnm33(t3ry bva8 h t 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 1plz jni7;g (.e8.0 $^{\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 chil56u9 5k fchex*yvsg/)aw3g6 khaix p0 wyt:-gd’s hand at sea level and 20.0 $^{\circ} $ C. When it reaches an altitude of 3000 m, where the temperature is 5.0 $^{\circ} $ C and the pressure is only 0.70 atm, how will its volume compare to that at sea level?    times the original volume

  Calculate the number of mo1cs7 ks5c wf/ dim9of7lecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How many molecuoxf n.,0 ww7iwles?    mol    $ \times10^{25 }$ molecules

  Estimate the number of wsq1o:loyjh3 swsts kw(*.7: (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 volum- ; aj+2odb .2sl8lx nskz 2c6o,qxzjle 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 azqyp ,u d01 gjo*d1)w.vgv2 sbre in each 2.0-L breath you inhale that were also in the )v yvgg 0oduw*j1b1qz2 sd. ,plast breath Galileo took. [Hint: Assume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of an oxygen 7 9ucwt. sdaiz 05xp5hmolecule at STP? h7wzs d0 i5 9t.cxupa5   $ \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 spee6 vmr c-7 .jxu8sdj;+biug,avd of helium atoms near the surface of the Sun at a temperature of about sm+r,x c;gub6jvd uva 8.-7ji 6000 K.    m/s

  By what factor will the rms speed of gas molemx2hofs3da8 *(vm a5mcules increase if the temperature is increased from 0*3xfmova8 hm dm(2s5a $^{\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 spalbe(z5c/ 9 wwwn2+az)jb:f im1d.fjeeds, given in units of km/s: 6, 2, 4, 6, 0, 4, jcaa ze (lwb fw2ib19/w)f.d5mj:+zn 1, 8, 5, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in +ju 5md4kzxr- ;r 5vwqa gas at 20.0 $^{\circ} $ C is to be increased by 1.0%. To what temperature must it be raised?    $^{\circ} $ C

  If the pressure of a gas is doubled while its volume is held constant, b hu;.j, o;qvw5ov8rriwe 0qz9y what factor dw ,oz qu.8vr0vqh;;oe9iwr 5joes $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is ryeg5 ywxbvn 52+a. m,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, t9 bz 9q.m;ozxft4a.lr he ratio of their rms speeds is equal to the inverse ratio of the squ9.r ;. zzo9fmqxblt 4aare roots of their molecular masses.

  What is the rms speed of nitrogen molecules contained in anz ptn z8:*)sia 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 c/hy8rp,gyilolm 4g 1n3y9 *ean 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 nitrogen molecules a g 39aq+l kah pw)i(,g5akyk3 ;feowf;t STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular mass is 89 n-ztw.g-b rot;a4;e 5k v,q zxu in a living cqo-5wazv4,z e rx;.ngb-k t;tell 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 c:z0 etob76fp fan 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 uraniumtj*kh:dsb 3r3 , $^{235}$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 fn3xz ,g-g tpc.k(4jnb n50z bwhat phases can $CO_2$ exist? (b) For what range of pressures and temperatures can $CO_2$ be a liquid? Refer to Fig. 13–21.

Water is in which phase when the pressure is 0.01ce 2pqf i/et 1jk*k3*d atm and the temperature is (a) 90 ec*/kj1 32qp fi* tekd$^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if tuky7rb8 bl d763sm*v the humidity is 50% on a day when the temperature is 28ybmvb7 3u7 dks6rt*l5 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water boe h+edjx.hi2nt2q1b k i6(wk+ wo1x)pils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular0 *-pi i vw;bbd/pgi9z place in the mountains is 0.72 atm, estimate the temperature at which water boilsipb 09/g;vwib p*zi -d. $\approx$ =    $^{\circ} $ C

  What is the temperatu75 g/c *vlaacb lz8,zure on a day when the partial pressure of water is 530 Pa and the relat5a*zc7vgcabz 8u / l,live humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the tempe6xp yzrqypa 4 -2b-c5jrature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pr: o :cik5qeep/essure cooker if the water is boiling ie:/:c oqkep5at 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 a room of vrpav )p)j9ebp1zj9 5b.2tu saolume 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 w/ 56hhyy7gjj7s/,zxd/wzxo $^{\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 8m(+1apk ,+cmrwvmdw glycine molecule (see Table 13–4) to diffuse a di v, mm++(kmwdpw8cr1 astance 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 pt-jb7jtd;33 .wsced tiny tubes called tracheae. An average trachea is about 2 mm long antds; t.jbed73cwj-p 3 d 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 bee8:l0s o+tee6rj6t rven calibrated at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A precise steel tape measure has been calibrated at 2-k ydh 1b.::cdaomy;91pmf ah0$^{\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 xd qrm,rnge a88 3;qs2temperature. How much error will be made in a recipe calling for 300 mL of cool watemr ,38xa2snqqrg e8; dr, 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 heliuxeg v-pwql1;g1s)h-i;72v gb sgf.g bm gas cylinder is initially 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. Whatgb )s;1x-qh1;7sb-gpviwve.fl2 ggg fraction of the original gas remains in the cylinder?   

  Estimate the number of air molecules in a rooh bp 09k-erfr7m of length 6.5 m, width 3.1 m, and heig79hr-brf 0epkht 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 onee is;:o-t qm 4kk*sd8n 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 av pqz x93goo,m3ici7g;u q5(duailable vacuum techniques is about ;xpgu9d oo3c ,7(mqiugz 3iq5$10^{-12} N/m^2$ 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 j; bu53g*xri y v+m,eznxmqo,j 0g2u;L when 10 m below the surface, to what volume wog yiu,0gm*oj q2;nx,rv3;e5j xmb+ zuuld his lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmosphere at a spee-5rr(iy o(f* o3asmtu d of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this speed correspond to what temperature? (Because of this high temperature, the nose of a space vehicle must be made of special materials; indeed, part of it does vaporize, and this is seen as -sty5rifu(aro*m o3(a bright blaze upon reentry.)    K

  The temperature of an ideal gas ix2sc6dhss ;4g3q0 2w jz2mkyrs 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 770mt.qd6*7v bn hv;zl6f e$^2$ (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 Eart:s7f ja-.wl*8gdlzq3 sj ,d yuh, estimate the total number sy. 3dqj,*z lufa:8 jgl-w7sd of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen ntyjcal137t :molecules contained in a 7.6$-m^3$ volume at 4.2 atm if the total amount of nitrogen is 1800 mol?    m/s

  A standard cylinder of oxygen used in a hospi y:ypcy 6t kv7w4,wwb)g,r e.ltal has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How,yw lry y,gc4) 6vbew7wk:.pt 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 4 eldloek;glnuj flka3:0i:4 c9/w7p of liquid mercury at 0$^{\circ} $C. (a) If the temperature is raised to 25$^{\circ} $C, will the cube float higher or lower in the mercury? ----待选择----lowerheigher 
(b) By what percent will the fraction of volume submerged change?    %

  The density of gasolin hszof+b8,h/ie 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 sn j2fiyun-jjh4-)d b5fbw ;c0 ougly 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 ontocdrgm o (k8 iv5,-b10m 4ndbipl l.6pjb; q.oj a glass jar at 20$^{\circ} $C. To help open the jar, it can be placed into a bath of hot water. After this treatment, the temperatures of the lid and the jar are both 60$^{\circ} $C. The inside diameter of the lid is 8.0 cm at 20$^{\circ} $C. Find the size of the gap (difference in radius) that develops by this procedure.    cm

  The first length standard, adopted in thvn8k,f gsd3y :e 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, h/ wg-se40 *+c1a sjsgcrhrg3gas 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 froex,zg uhy el+0;sal. o(5mchivs8* x3m 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 gravity by tenni kc :skk,s8r67hg.uf i5l-ofus balls thrown vertically upward at kfshc5u 8, rf6-k7k. silu og:it. How 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 3.00-cm-db2-zg vgqc(1r iameter (spherical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and th r-gcgv2b(z1 qe air behaves as a perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total water vapor prehv xxg- lj9/p-ssure in the air on the following two days: v pxxg /hjl9--
(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 differenvs2 oovg(o+. ;mdd8/u3hunlqo ;6h sq ce in the density of iron at STP, and when it is a solid deep/; ;ogs2sdqd(u3 +uho6on hv8vml.qo 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 idealmj1l1d0 )wd rai-vkp9 gas at constant pressure, the 01) l1rpmj-dkiad9v wcoefficient of volume 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 consl7jy n(2m i:z( yhsk7kov 4c*btantly dehumidify their cellars to prevent rot and mildew. If the cellar in a house (y 2cvb7(h(mkszij* 4lknoy :7kept 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