Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodic table i mo/sfges ;):h+xkoggtjs)b*:z) *dor :dktz * /bgfo e*;s))g+joi g:shxms) Appendix B.

Name several properties of materials that could be 1j k0vam, w/mzexploited to make a thermometeaw/0z1km jvm,r.

Which is larger, 1 Ccj7bn1ef/6 fv:z.rx fmj*g)v $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, bu46tthwmay0sd 8 * es6ft B is not in thermal equilibrium with system6dt e 4mas*wy0fh8t s6 C, what can you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to a strip of iron n7uv-k x yvacj7 oj34*m+n:houk8.zl. When heated, the strip will bend. Which metal will be on the outside of the curve? [Hint: See Table 13–1.] W+c 4 u7kaunnyo-lmvj*x z.h j78 ko:3vhy?

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 lineas )q ./ iiqwi99-jn8ka.dre hvr 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 thermost(3 /kw4yc24u- ztp ami fzag5zat used to control a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch is a glass vessel containing liquid mercury that conducts electricity when it can flow to touch both contact wires. Explain how this device controls the furnace and how it can be set at different tempeapt52 4yauz(m3 4gfw i/ckz-zratures.

Long steam pipes that are fixed at the ends often have a section in 17i; isiy(i2 atyewf; the shape of a U. Why7aei ;yys;ifw2t(i i 1?

A flat, uniform cylinder of lead floats in mercurgp:g +i.kfc0 oy at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometer is firs*8 1s4-f y;( uceyqcxa8vmceh)w(el z t placed in a hot tub of water, the mercury initial ma*s8huc4 eyl( e ec-1(c8zf yq;x)wvly descends a bit and then rises. Explain.

A glass container may break if one part of it is heated or coolezqb)um l+t;u+ d more rapidly than adjaceq; blu zt)++munt parts. Explain.

The principal virtue of Pyrex glass is that its coeffi9f/yphd o/ 7mkf)xhh;cient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance kfxh/y7/do9) h hm ;fpof Pyrex.

Will a grandfather clock, accurqrfgxt , 7azeh+d;6 hs2s9+ab ate 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 sod1e/gjn ib/ k:ga will cause its bottom and top to bulge so badly the can wi/e 1ib/gnkg:j ll not stand up. What has happened?

When a gas is rapidly compressed (sam,di2/.nee /o xp kjy2p wd.euu8o;9ay, by pushing down a piston), its temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperature using the kinetic theory, in particular noting what happens to the momentume.jd ,ae/k oix o/u2pw.p;2me9 yd8un of molecules when they strike the moving piston.

Will the buoyant force on an aluminum spherhd,* ivg- vf/b*rpc h(e submerged in water increase or decrease if the temperature is rhgid*/-vc (*h ,fp vbincreased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetc7pyj3z4q)g mq/ + xwcom n41bic theory and the relation between average kinetic eneygqzcb4 cn4m17 qo/jx3 pm)+wrgy and the absolute temperature.

Explain in words how Gay-deb57)/ rc kynvo) gl7Lussac’s law follows from kinetic theory.

As you go higher in the Earth’s atmog1 2qhs 3uwoqk;( v.*pyvs4oosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed an ou (w06j/cxoq tbject 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 Moon’s smaller mass. Explain why the Moon has practiuo6wc 0q/(xjt cally no atmosphere.

Alcohol evaporates more qui:tgk un3ej2z0 ckly than water at room temperature. What can you infer about the molecular properties of one relatjkte3 :nugz20ive to the other?

Explain why a hot humid day is far more uncomfortable tha4+go 5;t ikfnfn a hot dry day at the same temperao nki5+fgtf;4 ture.

Is it possible to boil water at room tempem* j eb/nbwh7r x 4i5z8+yd.) svysld7rature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the humidity is diz3wdyh q2c f dd,cocz;w05a :/fferent. Which is more dense, the dry aiaz cq hcd 0/o:,wfd5c z23;dwyr or the humid air at the same T? Explain.

Explain why it is dangerous toxu 7)x-3c yw0.pzehxu7om z*f open the radiator cap of an overheated automobile engi7.uo x 3h 7fyzwmpx*0)z xec-une.

Why does exhaled air appear as a little white cloud in the winter (Fig. rai/m o t+kk;m),h,jo13–28)?

  How many atoms are there in a 3.4-gram copper penn4x ,;q.:-l( -yaewb b hbjihfny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold rq.xyssgv6 mj35 ;wf 6qing compare to the number in a silver ring of the s3;6qms w.6 x5sgqyj fvame mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. )/gxb* . ecc.rf kpp2fWhat is this on the Celsius scale? ef.pcrbk/ .p2fc)* gx   $^{\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 telwqg +um44/vw ytf(q(mperatures 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 h3 3qk0ih ;kppgas length 11.82 cm at 0.0qh3ipg pk0; 3k $^{\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 builtswn:e cv7 )s/n of slabs 12 m long (20 $^{\circ} $ C). How wide should the expansion cracks between the slabs be (at 20 $^{\circ} $ C) to prevent buckling if the range of temperature is -30 $^{\circ} $ C to +50 $^{\circ} $ C?    m

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

  The Eiffel Tower (Fig. 13–29) is built of wrought iron apbi65jct t0nx1proximately 300 m tall. Estimate how much its height changes between July (av501bji tcxn 6terage 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 are often used t)n jp8u ;lq(tand the rivet is cooled (usually in dry ice) before it is placed in tp)t;qln (8juthe hole. A steel rivet 1.871 cm in diameter is to be placed in a hole 1.869 cm in diameter at 20 $^{\circ} $ C. To what temperature must the rivet be cooled if it is to fit in the hole?    $^{\circ} $ C

  The density of water at 4 eg2fo 82y gwt:$^{\circ} $ C is $ 1\times10^{3 }kg/m^3$ What is water’s density at 94 $^{\circ} $ C?    kg/$m^3$

  A quartz sphere is 8.75 cm in diameter. What will be its ch7w56nli ux pfb/ m-2asange in volume if it is heatedpinxa u wmb/sl5627f- from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350.0 mL of wadokesl9k .j5eg*idm+ 1h:f y;ter 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 xn*4 vc y0/ob l6qw),yy0ac enti/ht9 of water at 20 $^{\circ} $ C completely fills a container to the brim. When the container and the water are heated to 60 $^{\circ} $ C, 0.35 g of water is lost. (a) What is the coefficient of volume expansion of the container?    $ \times10^{-5 }$ /$C^0$(b) What is the most likely material of the container? The density of water at 60°C is 0.98324g/ml.

  (a) A brass plug is to be placed in a ring made of ironkemit )-b-;r dkbl3 s;e+iac. . 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 vesscln5 irt-pj6aa,wl 3, el so it can expand in essentially one direction only, show that the effr ac5t ,wilp,3lj an6-ective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change-t4t pa ix 3i4b92kweyp+7kx6h2xy nr 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 coefficient of linea(owc6wm4 yf (k8hhx /cr expf8 64/w(ykmo c(xcwh hansion $\alpha$ 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 isotropic4 hzz3 n0-chfx 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 grandfaqd h38y(y3 bc(r1w qaxther clock is made of brass and keeps perfect time at 171cwhdar xbqy q(y3( 83 $^{\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 0.oy)( air:n oql5jvu(9+m k nh3140 mm. The bulb has a volume of 0h5+(u nay( )n:m3jlqov9i ork.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 whew 6jq*e k,nm6fel of radius 0.41 m is rotating about its axle on frictioejq*kmf6w6 , nnless 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. H dg1-s gqgt4 y:b9kha 0r71mnvow much stress is required to keep it at this length if the temperature increases to n1d -h: 4 0mb91gg7rvkst ygaq35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steelywn0 : z5crkypc2qqx ;xub0 34 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 at 20(a 4- e,*yqozm2ktl xa$^{\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 t ;xk8,frds(p4k ab:r:
(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 hm0br:b593vx xn. azpupjx 00Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures inty+x 4d9gwx m: ea*u*c the interior of the Earth and Sun are about 4000$^{\circ} $ C and $ \times10^{6 }$ $^{\circ} $ C respectively.
(a) What are these temperatures in kelvins?    K    $ \times10^{ 6}$K
(b) What percent error is made in each case if a person forgets to change $^{\circ} $ C to K? $\approx$    %(Round to the nearest integer) $\approx$    %(Round to three decimal places)

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

  In an internal combustion evp,qy ;7xw)pieecgvs,0 4c yi/gr 16wngine, air at atmospheric pressure and a temperature of about) 16 qvy s iwy,/p4cpvg7egrecx wi0,; 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 densityuk1213nojlupo;5 mh l of oxygen at STP using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of nitrogen y z efasz(5)hg l/ce30($N_2$) 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/a +px4lvbyd9,r)lew kg of nitrogen ($N_2$)
(a) What is the volume of the tank? $\approx$   $m^3$(“Round to one decimal places)
(b) What is the pressure if an additional 15.0 kg of nitrogen is added without changing the temperature?    $ \times10^{5 }$Pa    atm

  If 18.75 mol of helium gas is at 10.i2 ua7c) /eqr,ox ap/g: *agqv0$^{\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 insid j+x6a7cf3pb1gfye 5 fkuo7;fe a 35.0-L container holding 105.0 kg of argon gas at 383;k7py5bf6g 7x+ufa1ef o j cf5 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg o5.xo)t;sga1 hc q(ve18sze mzf $O_2$ 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 achie(n+n7f g8nlsfves its buoyant lift by heating the air inside the balloon, which makes it less dense than the air outside. Suppose the volu8 7snnn+f(glfme of a balloon is 1800 $m^3$ and the required lift is 2700 N (rough estimate of the weight of the equipment and passenger). Calculate the temperature of the air inside the balloon which will produce the required lift. Assume that the outside air temperature is 0 $^{\circ} $ C and that air is an ideal gas under these conditions. What factors limit the maximum altitude attainable by this method for a given load? (Neglect variables like wind.) $\approx$    $^{\circ} $ C(Round to the nearest integer)

  A tire is filled with air at jw bfi26j;s* f15 $^{\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 1w0sws m; 1qhk)8.0 $^{\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 escapep6a +c o 3cs2f6+cjxqys a child’s hand at sea level and 20.0 $^{\circ} $ C. When it reaches an altitude of 3000 m, where the temperature is 5.0 $^{\circ} $ C and the pressure is only 0.70 atm, how will its volume compare to that at sea level?    times the original volume

  Calculate the number of molecules / rdv 9 z:4nogn.$m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of wate ebwv) wnm ,j7y,uyg7c4+l7j/o;yncm r are there in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) moles+gpt*i.ix ov;6f(al a ,    $ \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.-aze/- fx p vgo yup),ud50et: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 molecuyf+w*u,0ccd 6a kgg-xles of air are in each 2.0-L breath you inhale that were also in the last breath Galileo took. [Hint: Assume c*x0g,k-wyu6 cfg +da the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the aver3 o ryf(asz03rage translational kinetic energy of an oxygen molecule at STP? 3 0ysfr(arz3o    $ \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 surf,9 2p;i )ixzrqfwq5wk 2n)cqk ace of the Sun at a temperature of awq, ;)nz9p 5x 2)icrkwqq i2fkbout 6000 K.    m/s

  By what factor will the rms speed of gas molecules increase iqf( 0jzviln:7n5 skd*f the temperature is increased f* n f5 n:disq(0kjlz7vrom 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 un/b/dbl-.m lu5,y tui vn1phx5its of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 1 x.um v/n5,hdtybl 5ilp-u/b 5, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas atv):4*lv wbp h3jx/ajg 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 constahq)zo : m3 zxa0pq/10yij kzv;nt, by what factor does;0kj zoa1y3 vzz qmpx q)0i/h: $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is g.tq9v*nen;7pk hqdye/vk -ou-1 i 2jyiven by $v_{rms}$ = $\sqrt{3P\\rho}$ where P is the pressure in the gas, and $\rho$ is the gas density.

Show that for a mixture of two gases at the same temperature, the ratio of th*( zbz7j acxg3eir rms speeds is equal to the inverse ratio of the sq3 *jx c(gaz7zbuare roots of their molecular masses.

  What is the rms speed of nitro my3u 4o930 lriq5bhmwgen 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 o6xz(s ;cjp 9w,o:plpfxygen 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 a1;7arax2ty hn.i qpr3t STP?    $ \times10^{-9 }$m

  (a) Estimate the rms spj,j5 x0x8yejd eed of an amino acid whose molecular mass is 89 u in a li8j,jd5xjy0e x ving cell at 37 $^{\circ} $ C.    m/s
(b) What would be the rms speed of a protein of molecular mass 50,000 u at 37 $^{\circ} $ C?    m/s

Show that the pressure P of a gascxwxir19nx-/(4 l vaq can 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 uraniumd kt.ug+ 8tz2u, $^{235}$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 pha3k lm qv;3reib/u ,3sjses 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 them+)o)n0g9 eqnb,:cme; ap lbcn8vt4 o pressure is 0.01 atm and the temperature is (a) 90mcvq:4,o;gbnob)+ lec) mp0 9t8nn ea $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity is 50% on a day when the . 7sr5cq 4go.0o zekup4 nbw;utempera5us ru0neq. ;wg 4bopkc.7zo4ture is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at n;ilfg oo.6kf3 1aoc :k 6brz)a place where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is()8 p+ .gt wu:ydstzfy 0.72 atm, estimate the temperature at which wa ft8( gy+y )t.puwzds:ter boils. $\approx$ =    $^{\circ} $ C

  What is the temperature 9 zs xfm1*e2gsc) 6tjoon a day when the partial pressure of water is 530 Pa and the relative humidity is 4m1* z6o)eg stsxc2j9f 0%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the temperature is8jt wn -gzdrlup72 i)8-g0 vdn 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressurex m4 csk wo:i)na +uf q0+a0ra3m-+qu4h4um ov inside a pressure cooker if the water is boiling at a temperature of 1oa q+)+va4m f0sh nmaikmu4cu-r4:uo0wqx +3 20 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in awqb 5:qh*u;(hv xo1p h room of volume 680$m^3$ at 25 $^{\circ} $ C is 80%, what mass of water can still evaporate from an open pan?    kg

  Air that is at its dew point of1 9,u jr*gjrmcl f2xh- 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 glycaqut/gp7 m 0uc(yd81n 6,w e+upqf,xsine molecule (see Table 13–4) to diffuse a distcpumsqw ea ,y1q/x p+d8g, nu7(u6f0 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 insectf,d2 kongqh 13s to the interior through tiny tubes called tracheae. An average trachea is about 2 mm long and has cross-secti 23q,h o1gndkfonal 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 mea-k 7ggssy t 9sc00 p+b-euox-3t -ckhbsure 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 precise steel tape measure has been calibrate7c ;bz ;laq2tj765yoe*wc r vpd 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 wasqhu0my6y *9 ccqd1op mp-q*i8 calibrated at normal room temperature. How much error will be made in a recipe calling for 300 mL of cool water, if oq- h9ppc8 qd*i1uq y0m6c m*ythe 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 gcvl/2ahqy* *gusx -t /as cylinder is initially 28 atm. After many balloons have been blown up,ty2vg*q*sc- // xalhu the gauge pressure has decreased to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air molecules in a roh:jl :ycgdq,lnmfm, b3n,n xx0;m)j*om of length 6.5 m, width 3.1 m, and hei ):0:nxj,*b myndm,chgnql, lxmjf;3ght 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 at(bmj ptpmk.23qn4h 6 .ul0 dgbout 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 teck6: +rwu dj+pnhniques is about: du6+njpw+k r $10^{-12} N/m^2$ At such a pressure, how many molecules are there per $cm^3$ at 0$^{\circ} $C?    $\frac{molecules}{cm^3}$

  If a scuba diver fills his lungs to full capacity of 5.5 L when 10 m below te16x mw fc1(jw3(ofluhe surface, (ufx6 (w1cewj 3f1molto what volume would 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 speedg:7hmm )o(ihx3i hg; t of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this speed correspond to what tempe)7ggi:x mm hh i;oh3t(rature? (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 a bright blaze upon reentry.)    K

  The temperature of an ideal gas is increased from 11e -vo:/2 wopmr0$^{\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 o)xiugl*q,ixur y;q8 s ko:4+cf 770m$^2$ (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 atmospheri32 himi0qel 3ic pressure at the surface of the Earth, estimate the total number of air molecules in t3ili 2i0h mq3ehe Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrog zjib 41pt/+boen 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 4vw* hznq 7ku0obb4b0 hospital has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure, is constant at 2.4 L/min.q* w44 kzhv0uo70bb nb $\approx$    hour

  An iron cube floats in a bowl of liquid merv4v 9 jl x2.j4,sieyurcury 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 gasol1mb ihda,l(7gine 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 spwvj)vnz11w ;)w c d*qnugly around the Earth’s equator at 25$^{\circ} $C, but then was heated to 45$^{\circ} $C, how high above the Earth would the band be (assume equal everywhere)?    m

  A brass lid screws tightly onto a glass j-yb+ zr .osg 92:jlbtjsre +8zar 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, adoptd bufa 8guwg9s:ts//) ed in the 18$^{th}$ century, was a platinum bar with two very fine marks separated by what was defined to be exactly 1 m. If this standard bar was to be accurate to within $\pm1.0 \mu m$ how carefully would the trustees have needed to control the temperature? The coefficient of linear expansion for platinum is $ 9\times10^{ -6}C/^{-1}$. $\pm$ =    C$^{\circ} $

  A scuba tank, when fully charged, has a presno6b b*oo;) wosure 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 t-b- gpk*x t ,il)wn9aphe 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 throw/h 3;u:8y,cef atwpovn vertically upward at it. How many tennis balls per second must rebound from the lid elastically, assuming they have a massf v8ath:3 c pe,;ywou/ of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter 95c .s:rbc9wg5vvdhrl pb g(((spherical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and ther5lh 5ccb(.vv s9:d (rgbpgw9 air behaves as a perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure in the air 0kg/;x mra1tdmk:c s4on the following two days: mxcdtrgk4/; aks :1m0
(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 ofx u6oamv;9h.v iron at STP, and when it is a solid deepa.xm69 uov;vh 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 8xlc5vtanw0jn 8;s 8uconstant pressure, the coefficient of volume expansion is equnv88nwx 5al 8st0;jc ual 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, peozi/f l fny:x*,b7f:bc ple constantly dehumidify their cellars to prevent rot and mildew. If the cellar i*yf,z7/n:bx :b clf fin 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