Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodic8:uifvunh*x+0 pyl d0 table or Append:di*pxny uuv+f8 0l0 hix B.

Name several properties of materials that j8gf)h)srhv,5:qrbv o+x 1w j could be exploited to make a thermometer.v gwrr8hjo+,hx jq5b s1):v) f

Which is larger, 1 Cgf 7yh8ks6q k+ $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equid6ku dw h6bm4pry 27 nk:boe3,librium with system B, but B is not in thermal equilibrium with system C, whatpohn eb2 m6:uk4b,3 7dry6wkd can you say about the temperatures of A, B, and C?

A flat bimetallic strip conszfru3sc:wz.b-* rjhy+ *i eu-k0 bxt u,z5u- kists of aluminum riveted to a strip of iron. When heated, the strip - .,cy z*b0rh 3wj: bzxs-+ruktkue u-uf5z* iwill bend. Which metal will be on 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 co*rqofg+,uwsf2u.n8 ,azv9 8pt9 .ybjv b9phbefficient 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 simpls8+u 1b1zkvu l jh rxqlc3)-0yb4g, zke thermostat used to control a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch is a glass vessel containing liquid mercury that conducts electricity when it can flow to touch both contact wires. Explain how this device controls the furnace andh ,x+v -usky gcu03lq1kzzb4jlrb 18) how it can be set at different temperatures.

Long steam pipes that arw)c u- +/wlrcozbzwrt+38n, be fixed at the ends often have a section in the shape of a U. W+-8 l rc+zz3b wwc),/nuowt brhy?

A flat, uniform cylind;f an849 vnhxoer of lead floats 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 thermometer is first placed in a hot tub of x nx:7s20ppoyq / ofxp0b 6dxfjy76l. water, the mercury initially descends a bit and then rises. Expx:p jf2f6lx s6py n/p qo7o0.bx 0d7yxlain.

A glass container may break if one part of it is heated or cooled more rl jyrp 3v79n he*yo8-kapidly thahvy *pol-r 8 9j3e7yknn adjacent parts. Explain.

The principal virtue of Pyrex glass is that its coefficient of linear expanbeno;,iw 77f6bnzq 3n sion is much smaller than that for ordinary glass (Table 1iez7 nbonf ;,wqb 37n63–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accul+p-fx,*oodu.c8; q ku fg2zfrate 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 bal(z5 qux+,lusw :4)odgimjv 5dly the can will not stand up q45ilgd :s(mx l o,+u)zwv5uj. What has happened?

When a gas is rapidly compressg) mik9hxj/ z (i dj+xa:;0mheed (say, 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 momentum of molecules w0)jmhex hjdkz ;mx9/a:gii+( hen they strike the moving piston.

Will the buoyant force on an aluma25 3c+:eks1ejpj2 ug z su9stz cc/xfa+g-;pinum sphere submerged in water increase or decrease if the temperatu:z;ts5 1g2jcge2juze-a upa9px fck+3/ sc + sre is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theoryu 1pbxj(bg78 x and the relation between jx8 bp(7xgub1 average kinetic energy and the absolute temperature.

Explain in words how Gay-Lussac’s law follows from+l0 4u vbr x z57zzf1ocj.,cr wl4+chd kinetic theory.

As you go higher in the Earth’s atmosphere, the ratio of y(-fw 7dk4-z qziv /zk;1bken$N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Eart( -lwzxp l,2z78b gthyh refers to the minimum speed an object must have to leave the Earth and never return. The escape velocity for the Moon is aboulp-txbzh7(gwy,2l 8 z t one-fifth what it is for the Earth due to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly t;rgqs-e z;w 9jhan water at room temperature. What can you infer about the molecular properties ofj; - 9qszwe;gr one relative to the other?

Explain why a hot humid dayzqt) 5r3 j5oa/md e1rd is far more uncomfortable than a hot dry day at the same temd r )3q5a/ r5tojedmz1perature.

Is it possible to boil water at room temperatq glm 2g0q5:gwure (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air tempef*kwyh0q: (peo t qo2)rature is the same but the humidity is different. Which is:ef wq o(kt yhqp02o*) more dense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator tokcoo2 + nh;+9wfvo:cap of an overheated automobile engine+ oct owoo:vf92+; knh.

Why does exhaled air appear as ahn-1 ,f fy3q,yvx h3ir little white cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram covnh2w. ebcu: n p0;jl6pper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms i7/12syoi o nman a 26.5-gram gold ring compare to the number in a silver ri7 1 moa2siony/ng of the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken tb9 4qs jx2dx2v e:l/zho be 68°F. What is this on the Celsius scale? 2 xxzv:/qbe4dlh9sj2   $^{\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 lowarxp)-uboel.eb7 ,i. 9e8j nqest 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 column has l.e 3woc)o:gg i 0:j,aq h,xlelength 11.82 cm at 0.3)he, gj: wlolqx.i ao0gc :,e0 $^{\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 builxn1da2z 5cnh liq0j7-t 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 approximately 300 mhdhj2: *ruj0h1yi emn h/q u*7 h,4ucv tall. Estimate how much its height changes between July (averagi0u r1 nh2d / yhjq*uu*jhmhe:7c v4,he 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, ri lbnlw bd)64,(wjmgk 1vets 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 placed in a hole 1.869 cm in diameter at 20dmbgl64jn1w bwl() ,k $^{\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 q0(.uhjv-cg dnm,.i yp:l zgy j vr7/74 $^{\circ} $ C is $ 1\times10^{3 }kg/m^3$ What is water’s density at 94 $^{\circ} $ C?    kg/$m^3$

  A quartz sphere is 8.75 cm in diameter. What will be its change in volume5i j 0a-)q lvrc4ncrt m0kko. 8.ncx/a if it istc r ql4a-xo8c) rm0av/k0..jkncn5i heated 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 qw)8c -/xai qmwater 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 waterpo4( .veq: zpy 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 pb 7blj +v lmrhg)7t45mlaced 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, narrow vessel so it can expand in essen6l6nif2tfb g 6 ;dyh9utially one direction onl;fl 9ubdh6gi2tnf66 yy, show that the effective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the densityi i/4n2+ybu uinil:.(g rxuq6 $\rho$ 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 coeffxs 4fr;fw4ljh( -5ln.g ulbpwy2 h(:z4tq*nyicient of linear expansioyhlbxlh :yt n wql(uw(24*g-5n;zp f s.fjr44n $\alpha$ 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 soll/bcz2c-yu: eid, $\beta$ = 3$\alpha$ if the amount of expansion is small. $\beta$ and $\alpha$ are the coefficients of volume and linear expansion, respectively. [Hint: Consider a cubical solid, and neglect very small quantities. See also Problem 18 and Fig. 13–30.]

  The pendulum in a grandfather clock is made of brass ans9n3cj9h ; oqdd keeps perfect time at 1s3n9qhcj od ;97 $^{\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 inrxu ccn es,. z*9+l/e0zdud7eside diameter of 0.140 mm. The bulb haun9 eccdz/ ,0lz.eu*7s+exdr s a volume of 0.255 $cm^3$ How far will the thread of mercury move when the temperature changes from 11.5 $^{\circ} $ C to 33.0 $^{\circ} $ C? Take into account expansion of the Pyrex glass.    cm(b) Determine a formula for the length of the mercury column in terms of relevant variables. Ignore tube volume compared to bulb volume.

  A 23.4-kg solid aluminum cylindrical wheel .f,qgt(e1 mziof radius 0.41 m is rotating about its axl,ti (.ze1qgfme on frictionless bearings with angular velocity $\omega$ = 32.8 rad/s If its temperature is now raised from 20.0 $^{\circ} $ C to 75.0 $^{\circ} $ C, what is the fractional change in $\omega$?   

  An aluminum bar has theioiy+obuj1 ;1 desired length when at 15°C. How much stress is required to keep it at this length if the temperature j1iyuo1;ibo +increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-sectional a7dau;2ms3p z*dovy oj;d i1nkrf:a03rea 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 134.1pt21u g r+xgj.d9:z7ev 3eet n22 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 tempeiznw4.zl*z+u iq:t r:ratures on the Kelvin scale:
(a) 86$^{\circ} $ C,    K
(b) 78$^{\circ} $F,    K
(c) -100$^{\circ} $C    K
(d) 5500°C,    K
(e) -459$^{\circ} $F    K

  Absolute zero is what temperature on the Fahrenh pp-l.9;mwdiu eit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun are-uhv ::5(/qxrteu +lf fzb y;t 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 atmospheric8tui d;mp0yg5 pressure and a temperature of about 2mi 08;dt ygu5p0$^{\circ} $C is compressed in the cylinder by a piston to $\frac{1}{9}$ of its original volume (compression ratio = 9.0). Estimate the temperature of the compressed air, assuming the pressure reaches 40 atm.    $^{\circ} $ C

  Calculate the density of oxygen at STP using the i j1 h)e41svhtxt(56 a yjwgc(jdeal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of n k:og 7 f q/t*af+a.mnqg/uhic fg )pw8hx(6y9itrogen ($N_2$) 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 /rh :xddyz77 wnitrogen ($N_2$)
(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,abx k6 jj6)lu 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 *g+/djwqizgs dbw:m5ovh/bx64.w 5 h gas at 385 Kwdjq dm5vg.z x io6g+*/4:w /swh5bbh?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg of sa nr:8kc z-uhy53*xg $O_2$ gas at a gauge pressure of 8.70 atm. If the oxygen is replaced by helium, how many kilograms of the latter will be needed to produce a gauge pressure of 7.00 atm?    kg He

  A hot-air balloon achieves its buoyant lift by heating the air inside the bm6 j56kunf7+4 tpm mepalloon, which makes it less dense than the air outside. Suppose the volume 5u6t7mf4 jm pn+pk6e mof 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 8o7p( g9x0jl(u2y mjmqbeng1 air at 15 $^{\circ} $ C to a gauge pressure of 220 kPa. If the tire reaches a temperature of 38 $^{\circ} $ C, what fraction of the original air must be removed if the original pressure of 220 kPa is to be maintained?    %

  If 61.5 L of oxygen atoe9n jpp1nt 9 o7a5rd)srz3/ v 18.0 $^{\circ} $ C and an absolute pressure of 2.45 atm are compressed to 48.8 L and at the same time the temperature is raised to 50.0°C, what will the new pressure be?    atm

  A helium-filled balloon escapes a child’s hand ath coj03zqgd-zx 2jb50 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 nz)rj:(ocjtci-) t/p / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of waterlowg ; omr315r)qezs, are there in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) molezvgshp cf+2x8- wy qx +(w56hx5z-t/iuwzt,f s,    $ \times10^{22 }$ moles and (b) molecules of water in all the Earth’s oceans. Assume water covers 75% of the Earth to an average depth of 3 km. $\approx$    $ \times10^{46 }$ molecules

  A cubic box of volume 56v(ck1 nduj4dqf nw+*.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 ea 2gvt8yvd8t pj.9yb1 0vxcpttxn:3l, ch 2.0-L breath you inhale that were also3 1:cv,t8pbyp2xv 8tj yxdt. lt90gnv in the last 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 kinetih7fun +8 :diekc energy of an oxygen molecule at SThidn8f + uk7e:P?    $ \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/i d 3v: -f74ffo5 qzf7nqeoqf::eoe g helium atoms near the surface of the Sun at a temperature of abo-f7 f: v4 qfgfnq:doof 7e/3z :eqeio5ut 6000 K.    m/s

  By what factor will the re*4cbjbe e9f)g,y6b o ms speed of gas molecules increase if the temperature is incre eyb bgc,*4b69) ojfeeased from 0 $^{\circ} $ C to 100 $^{\circ} $ C?   

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

  Twelve molecules have the following speeds, given in units of km/s: 6, 2, 4, 6, x 0428 t gw1ud1tbunda0, 4, 1, 8, 5, 3, 7, and 8. Calculate the rms speeun1dax tw20 t14dbu8 gd. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas ai;(ww/.m tn6typ tpykkg6w6 )t 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, by whaz))u,v -cb bbu8wsh4z2 :qjsnt factor ds4 b2b:shz b,8w)q znjvu)-cuoes $v_{rms}$ change?   

Show that the rms spq6tufoc90)aur1b qp:eed of molecules in a gas is given by $v_{rms}$ = $\sqrt{3P\\rho}$ where P is the pressure in the gas, and $\rho$ is the gas density.

Show that for a mixture of two gases at the sameyese1s; xenj; ,p3*wq temperature, the ratio of their rms speeds is equal to the inverse ratio of the square roots of q eess;; 1wn,pjx*e3ytheir molecular masses.

  What is the rms speed of nitroge /x6tlwk/-jbsn 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 w5ibh/xu m:p6jzo-(xkw7k a9 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 betweekr )8ug(ro7h0n7peljrgnj /0n nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecule:vqb ./wbv3 j38* refyorswmhfd+:+ar mass is 89 u in a living cell de3fmj*y qbo v8sf+ewhv3: r/+ .:wbr 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 ;t(myo koy6,kbe written P = $\frac(1)(3)\rho v^2$ where $\rho$ is the density of the gas and v is the rms speed of the molecules.

  The two isotopes of uranium, r8*you/kk+vydrtf7p j x9,q)$^{235}$U and $^{238}$U (the superscripts refer to their atomic mass), can be separated by a gas-diffusion process by combining them with fluorine to make the gaseous compound UF$_6$ Calculate the ratio of the rms speeds of these molecules for the two isotopes, at constant T.   

(a) At atmospheric pressure, in what phases cap-obnqt90e* un $CO_2$ 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 mv c 6-3h8u.7u 5gaja v.aruaxis 0.01 atm and the temperature is (a) jc-6rvhuug. v3aux aa 7m85.a90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity is 50% on t3yc iae1 t-s.7vwx/d a day when the temperature is3eidwyxsa1 /t.-7t cv 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water bs8*achy q 4bx:oils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure a jqf:hiyhn68yvbhfd qo(5,4av73y 0 at a particular place in the mountains is 0.72 atm, estimate the temperature at which n38fqbh v47hjf(aya0ho6 5 viq:dy, ywater boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partiakxk+5z lk5;d bjni u8*l pressure of water is 530 Pa and the relativexi 8jzkk5dl;*n5+ ubk humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of waterr38fjbirna7- 5sl :tgz nqe g 5+l)6np on a day when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cooker if the 1tg3t;7l sh:t39,kovoc5i j hgwwe; nwater is boiling at a 1,t73hk t:cjio3v weht;;5l og9n gsw temperature of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in af lkk*hu.3 a/ ff1;tev 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 d1 e0 lwe(hf;bqdz l(:new 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 foxri; naugt,*3 r a glycine molecule (see Table 13–4) to diffuse a distance ;a gr, 3u*ixtnof 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 surfaj3+ c( xvx0ywcs r;;wxce of insects to the interior through tiny tubes callexcr+ wvwxyx;(cj s3; 0d tracheae. An average trachea is about 2 mm long and has cross-sectional area of $ 2\times10^{-9 } m^2$ Assuming the concentration of oxygen inside is half what it is outside in the atmosphere,
(a) show that the concentration of oxygen in the air (assume 21% is oxygen) at 20$^{\circ} $ C is about 8.7 mol/$m^3$ then $\approx$    mol/$m^3$(Round to one decimal places)
(b) calculate the diffusion rate J,    $ \times10^{-11 }$ mol/s
(c) estimate the average time for a molecule to diffuse in. Assume the diffusion constant is $ 1\times10^{-5 } m^2/s$    s

  A precise steel tape measure has been calibratermodn 30o+ f:.v(rsf rd 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 ha 0o7ww4 m6vhek+ib 7jes 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 temperature. How much e- ;whks )x(kxue4v7terror will be made in a recipe calling for 300 mL of cool water, if the-xvs ;x e4wkhu)7k t(e 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 nd3d0qyt q 1kue pt6xf+r5:pu6e7; lahelium gas cylinder is initially 28 atm. After many balloons have been blown up, the gauge pressure has decrease3ete 65+u1y 0; tupdq q:k6rx naf7dpld to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of ai i+wuyf)lk2+pul .9jwr molecules in a room of length 6.5 m, width 3.1 m, and height) l+w iju+ku2lp9wyf. 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 ov fz g- mousn 4f,ufa:ppbuf 305u6:y)f 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 vacuum techniques qvf, 8-zsy8 o ld:cym+is about,z qyfm :-c+8os vy8ld $10^{-12} N/m^2$ 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 luncd)psdij0 ) /xgs to full capacity of 5.5 L when 10 m below the surface, to what volume would his lungs expand if he qui)cpsjdd0) ix/ckly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmosphere3xfngephoqd 0 e5, /:z at a speed of ,pfgo5n /x3qd0: ze heabout 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 a bright blaze upon reentry.)    K

  The temperature of ana)s.p 4(i5y yd ivocy8 ideal gas is increased from 110$^{\circ} $C to 360$^{\circ} $C while the volume and the number of moles stay constant. By what factor does the pressure change? By what factor does $v_{rms}$ change?$\frac{P_2}{P_1}$ =    $\frac{(v_{rms})_2}{(v_{rms})_1}$ =   

  A house has a volume of 770m)o, h*(urrc z6kp-mtk $^2$ (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 /u-oj;m ,kx zrof the Earth, estimate the total number of air molecules im- /;jukor z,xn the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contained in a2z6dzjg0)szs5 7wa-ts:te ra 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 /3,dwt7hfmhbw x(7 g e+s(ndthospital has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rates/wd wt g,h(mhbnf77+ d3ext (, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats iwpz ,(j)-z:0ae mrztb2m r (orn a bowl 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 gasoline ai-ea)iqqs( rf d;dhx3 k7wh/8j7oq x4t 0$^{\circ} $C is 0.68$ \times10^{3 }kg/m^3$ What is the density on a hot day, when the temperature is 38$^{\circ} $C?    kg/$m^3$
What is the percentage change?    %

  If a steel band were to fit snugly arounji )ddm.n- fvgb790 vnd 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 orr-kc9ri9 ( g 1wder-mnto 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 thnxkf h hztk, /j2g1yprz1;d5 1e 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 pres)il f2hpj+miu /+* omq. xug5wsure 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 thx9p2(o/h ;zlmbpa:;qjxa sm(e 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 lidv(z :gmlr (wn1 is suspended against gravity by tennis balls thrown vertically upward at it. How many tennis balls per second must rebound from the lid elastically, assu mngv(1l(rz: wming they have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter (spherical) bubble)ye t 4gqp5c.l/ hbnw8 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 reaches the nw.g b)pel5y84/chqt surface?    cm

  Calculate the total water vapor pressure in the air on the following two dato9*rtn qan,0 xb16o*ukhb,b ys: nn,1t6uq9,o* rbxthbao bk*0
(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 whn0zw3pa7 en.e*e a2oaen it is a solid a7pe.eena*w3on a 2z0deep 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 c/ymil1 k ltf0nv:gy)kc7qa ( 2onstant pressure, the coe2:g1alm 7i( vf) 0 qtylyknkc/fficient 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, peopl1 9 iqv2z)j)jn-lenk3sw- idee constantly dehumidify their cellars to prevent rot and mildlesii)k)9-d2 vj e n zn-3w1qjew. If the cellar in a house (kept at 20$^{\circ} $C) has 95 $m^2$ of floor space and a ceiling height of 2.8 m, what is the mass of water that must be removed from it to drop the humidity from 95% to a more reasonable 30%?    kg