Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodic table u73siqa*mb4(zbdybc fe a9 2- or A 4bmbacb fdu 9s3 -iy(e27*qazppendix B.

Name several properties of materials that could be exploite0o/ +qrr7vgxk99 awbj d to make a thermomete07jo+ /wgr 9bvxqra9k r.

Which is larger, 1 C ;e+e 2o s nwryv,uc8b2$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibri 0yaxsspy / j u;vv)9p;xh qpb((+3hvgum with system B, but B is not in thermal equilibrium with system C, what can you j ; )9/bp+gpay;xyqhvhsu( xv30p(svsay about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum ra9 n(n2 ogxu3qe0 e;kg 15dezm loe2g/iveted to a strip of iron. When heated, the strip will bend. Whice5e odxg eg mna ;1 /kolzqe3g9n022(uh 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 coefbjhxm;4lpr+9, 0e f -nyep3yo;fnd6gficient 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 diagq9alry zxd8s (:xr,0xram of a simple 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. a0:,(8 qxx zysrlr d9xExplain how this device controls the furnace and how it can be set at different temperatures.

Long steam pipes that are fixed a71x, o23djdhs1ngkyy( 7hslf t the ends often have a section in the shape of dysn7h,ohy j21lxs f71 g (kd3a U. Why?

A flat, uniform cylinder of lead flo4iw s2;*vaz exats 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 hotb(o2;:7igh-epr o7 pnv 8dqwmr4 dmvb +(ns1q tub of water, the mercury initially descends a bit andbq78r1-g:o4mpper nqv ob h;m7sv ((2dw+din then rises. Explain.

A glass container may break if one part of it is heated or cooled more rapidly zmtc 0qizi0;u(1qp+u 2 tte/lthan adjacent parts. lt12tpt0 q0i(+q iu;zzec/u mExplain.

The principal virtue of 3vs; ,ewb1 hxyn28 neyPyrex glass is that its coefficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to th2ns 8wx3;b evyy1n e,he increased heat resistance of Pyrex.

Will a grandfather cd 4es4t r8pj(plock, accurate at 20 $^{\circ} $ C, run fast or slow on a hot day (30 $^{\circ} $ C)? Explain. The clock uses a pendulum supported on a long, thin brass rod.

Freezing a can of soda will cause its bottom and toz6ape0q5sfh g20)h htm/s k4op to bulge so badly the can will not )oafkh60sh42 zpqe s05 /hmt gstand up. What has happened?

When a gas is rapidly clup 2io3sueis)6.t,d+zu6 rfompressed (say, by pushing down a piston), its temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperature usineuuoli sup) 62fs,d.z6ti+3 rg the kinetic theory, in particular noting what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant forcee5 ,gehesk.j37hre ,j on an aluminum sphere submerged in water increase or decrease if the tempera3e,j hgjse e5h. k,7erture is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic t,xs0gu)7*8gcmy wp+lj yyg:cheory and the relation between average kinetic energy and the absolute temperature. 7 u ys,l):mxjg0g8+gycw*cpy

Explain in words how Gay-Lui(g + mlqxr-9kh)wy2 tssac’s law follows from kinetic theory.

As you go higher in thulf7p(7 78rm 0s*daqp g3quape Earth’s atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the E/jv j:s-h)zhz5q*fi 14 wotfjarth refers to the minimum speed an object must have to leave the Earth and never return. The escape velocity for the Moon is about one-fifth what it is for the Earth due to the Moon’s smaller mass. Explain why the Moon has practio4 - qzzvwjfs5j1t:/ih* fj)hcally no atmosphere.

Alcohol evaporates more quickly than water at room temper-+qgvxn6ny3 hature. What can you infer about the3x-g ny6+ vhnq molecular properties of one relative to the other?

Explain why a hot humid day ihn(.5; xrm(7xpwfaye *wd 9ps6y stf)s far more uncomfortable than a hot dry day at the same temp6f 9)dxtspsam7rx y e;fw5.p n w(y*(herature.

Is it possible to boil water at room95/lb1 srb/ qmzw ,nuyrjr)x: temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same r) x x9vms1)o85bbx(eektj(j but the humidity is diffe)tok5(e r 9vbmxxje 1b )jx8s(rent. Which is more dense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerous to open thmgam: (xlp9,we radiator cap of an overheated automobile engine. ,axw 9mp(lm:g

Why does exhaled air appear as a little white cloud in t5+ 1njx d8;3empx trymyun.m4he winter (Fig. 13–28)?

  How many atoms are there in a 38et t dq ee6;5/fvb3uj.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atk6xiad4 f3)s2ea h grn ld*4xqy4)j:qoms in a 26.5-gram gold ring compare to the number in a silver ring of tq 2 ief*r 4gkn)a)ja h4qlx4yd6d:sx3he same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. Whap;q wq34jr/h wt is this on the Celsius scale?wq;p3rq/jw 4 h   $^{\circ} $ C
(b) The temperature of the filament in a lightbulb is about 1800 $^{\circ} $ C. What is this on the Fahrenheit scale?    $^{\circ} $ F

  Among the highest and lowest temperatures 5lu0fy/bk:3 r: crcvw hmaw;) 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 length 11.82 cm at 5 t l.pwkzr g1*gc*i36kfis5pj n3io5 0.0 gkl j53*35it gsi6i51zwc*p pokfrn. $^{\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 (20wy 7q;+ g;jros $^{\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 approximatg70id h4x8;nkws9d8lh zp,s-ml)u sj ely 300 m tall. Estimate how much its height changes between July (average tempera 7z4g ,j) dssi -8mh8unxlh0dp k9;wlsture 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 ofwv t0cc y):nv,ten used and the rivet is cooled (usually in dry ice) before it is placed in the hole. Aty v:v) ,0nwcc 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-jvs +l+czxq y..wvk,-jg( n/5)jp vm8vji bh at 4 $^{\circ} $ C is $ 1\times10^{3 }kg/m^3$ What is water’s density at 94 $^{\circ} $ C?    kg/$m^3$

  A quartz sphere is 8.75 cm in diameter. What will be its change in volume if jm5 ovqe 1t/nam.t 5o0it iv 10qom. na5mjo5tt/e s heated from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to troh+1jqo37r(, f k mavhe brim with 350.0 mL of water at 100.0$^{\circ} $ C. If the temperature decreased to 20.0 $^{\circ} $ C, how much water could be added to the glass?    mL

  It is observed that 55.50 mLfs9) jjlqgr 4dyt)u7l.cl +7s 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 ofse go7n26li/(d fp /id 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 contaiq)4*u6ycwmu. s*kfc ) z2xzrqned in a long, narrow vessel so it can expand in essentially one direction only, show that the effective coefficient of linear expansion is approximately equal to the coefficient of v6 xu. s)zm*)fykzucr2 cqw*4qolume expansion $\beta$.

(a) Show that the change in the(7xywt.cfr / caib2v/ 57gshm 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 pl;* zqn;ovus 4tsk v(3.w6zqvvate of length l and width w has coefficient of linear ext4 ;nvsvv;w( q ukz.qov3s*z6 pansion $\alpha$ 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 soliu0b hazj)pk/sgtqu+ w --g;u3d, $\beta$ = 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 ba cyvgz(h +o9*) y.juhrass and keeps perfect time at 17y.y 9u*v+(hhazc) ojg $^{\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 0.140 mm. The k9pe * ux0/ly hvq2.uuqk.z )obulb has a volulveu)2/y. h k zp*9o.qqxk 0uume of 0.255 $cm^3$ How far will the thread of mercury move when the temperature changes from 11.5 $^{\circ} $ C to 33.0 $^{\circ} $ C? Take into account expansion of the Pyrex glass.    cm(b) Determine a formula for the length of the mercury column in terms of relevant variables. Ignore tube volume compared to bulb volume.

  A 23.4-kg solid aluminum cylindrical wheel of.9u4hs4juhd nx z6s 3e radius 0.41 m is rotating about its axle on frictionless bearings with angular s43uuhhsenzj.49x 6 dvelocity $\omega$ = 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 lengt 0pw,o0ikick (bz*qx -h when at 15°C. How much stress is required to keep it at this length if the temperap0qo 0w-i x,i(*kcbkz ture increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beamqvgopbl 7 -7knpsb+)r5*ik dkdrq(r 3f(mu15 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 td38fui lnlz 1:a-uv8 s i.xx,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 temper 27qftx95/qpesfs8cj(vrpb :atures on the Kelvin scale:
(a) 86$^{\circ} $ C,    K
(b) 78$^{\circ} $F,    K
(c) -100$^{\circ} $C    K
(d) 5500°C,    K
(e) -459$^{\circ} $F    K

  Absolute zero is what temperature on the Fahrenheit n )z7cs0vdb*l scale?    $^{\circ} $ F

  Typical temperatures in the interior92z gfjh * c:4va3dul2 kbm0uj 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 engivkjo zk96 l4r y8:plcfz.l zyqst 00,+ne, air at atmospheric pressure and a temperature of abouszrktqf:+kljp08c4zo z y6 0l v,y.l9t 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 usih, pn.wxfu ;x,ng the ideal gas law.    kg/$m^3$

  A storage tank contai 1,165rv .fb vknynsb1ls9cihns 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 c8/uq wj*49 e2wna)r .oui *zwuyzi3heontains 18.5 kg of nitrogen ($N_2$)
(a) What is the volume of the tank? $\approx$   $m^3$(“Round to one decimal places)
(b) What is the pressure if an additional 15.0 kg of nitrogen is added without changing the temperature?    $ \times10^{5 }$Pa    atm

  If 18.75 mol of helium ga7xy zm(+ u u;zaki8go7m,x tj8s is at 10.0$^{\circ} $C and a gauge pressure of 0.350 atm, (a) calculate the volume of the helium gas under these conditions.    $m^3$
(b) Calculate the temperature if the gas is compressed to precisely half the volume at a gauge pressure of 1.00 atm.    $^{\circ} $ C

  What is the pressure inside a 35.0-L container holding 105.0 kg of argon gas a t:my2v-+ l;nkv-b97 xvo-ba5dko ijkt vvjnlxdv2obb k+7t :y9k-m- 5-k ao;i 385 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kgcy:3x4di zd hm8i*gh(m,hc+ w 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 7)t 6z*j8tbic 5qbbnjair inside the balloon, which makes it less dense than the air outside. Suppose the volume of a balloon isc )i*5zt6 jb7jntbb q8 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 15kh g29czzl1,kwva9 n-4f c*gz $^{\circ} $ C to a gauge pressure of 220 kPa. If the tire reaches a temperature of 38 $^{\circ} $ C, what fraction of the original air must be removed if the original pressure of 220 kPa is to be maintained?    %

  If 61.5 L of oxygen at 18.0g+h- wo 8aimn4 $^{\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 c1jjd i/9lsi x:z1b,iphild’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 pghy1 yk/y mo .fkl wt619kx/7of molecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? Hc *ygjg( 2ljk-x2gvo 3ow many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (5)ia9,b)ovpoos wui- a) moles,    $ \times10^{22 }$ moles and (b) molecules of water in all the Earth’s oceans. Assume water covers 75% of the Earth to an average depth of 3 km. $\approx$    $ \times10^{46 }$ molecules

  A cubic box of volume xsiih)ty)zo0 z kx)/5 ir32td 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 ai6vmnw7ihq7 w ;j2sw5mu8m sb 5r are in each 2.0-L breath you inhale that were a 8mm;wnsv75w5q2sjuih b 76wm lso 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 translat () ;r90ix -dlvurbgd/t k-wkrional kinetic energy of an oxygen molecule at STP/rrdw-dtr 9(0k kglvixu ;b-)?    $ \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 surface of tsq3vw 1c f2fy:tj,t: the Sun at a temperature of about 6 tcv:t:j y2, w3qtff1s000 K.    m/s

  By what factor will the rms speed of gas molecules increase if the temperat ,kx y1mi4ie1o afqb35ure is i31m5abfq,4i1 eiyk ox ncreased 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 therdo6tcju jk5:h,/*ow c *tu2t following speeds, given in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. thu5jkoc jd twtc,uor:2 **6/Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecule;yo6g yy)6e0ej a *lhjs in a 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 heldox7 .gtt* dfi +91rm8bb0 ro5u cs9mfg constant, by what factor . c9 1gx80s9*bmu+firmot fr57dgbotdoes $v_{rms}$ change?   

Show that the rms speed of molecules in ; n.8q3 mxkv07jkw;:in q+y ociwxv(za gas is given by $v_{rms}$ = $\sqrt{3P\\rho}$ where P is the pressure in the gas, and $\rho$ is the gas density.

Show that for a mixture of two gases at the same temperature, the ratio o8st6kvjnysy4t:m/(dk3 g lcn: tms 8uao8) j+f their rms speeds is equal to the inversekt6g (sc:j/ v8ttn4 adu8:y+ osyjlsmk83nm) ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen molecules contained in an 1v (l tf0q6 lh5ynif;e8.5$-m^3$ volume at 2.1 atm if the total amount of nitrogen is 1300 mol?    m/s

  Calculate (a) the rms speed of an oxygen molecule a46a zoh t-hgk:t 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 at ge o0wr3h wra.xc/05l STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid who8/3 r+bfnevi jse molecular mass is 89 u in a living cell at 37brnei/fv3 8+ j $^{\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 g z(;7h9s oorfuwvl/o9iaq53zas 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 ursnkmtjd0 *p/ *anium, $^{235}$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 wcivx l/tey t )6n/e d4.;j4snpvww,5u 5jq(rmhat 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 ora(, qvtw/iv;xpq .. is 0.01 atm and the temperature is (a) i,pv.(rt.;v/xaoq q w90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximatakhywro +k:,a-csq8ffzk 8f3 h5) 4mvely) if the humidity is 50% on a day when the temperature is 2f-h3fs5c8+vwa fy, zkoa hm:q 4krk)85 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water boil4xm f vlrf8zglwq4b9+ 92 s1zds at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in jpzabz5w/b k))k(gjuft 3( 0b the mountains is 0.72 atm, estimate the tempa0k5b)u b3gjzpfz( )wk j /t(berature at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pre d(g9voy)t-ok ssure of water is 530 Pa and the relative humidity()d 9o- tkogyv is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of qywk x/l qfo2-; 6cn;wwater on a day when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate p-od,vg7wmb*lfc 9 k q825gr horessure inside a pressure cooker if the water is boiling at a temperature of 120gkh f,orm2qcl8-v9bw o dg57* $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room of volume /.1 cvruwi5mb 0ve2fs 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 o2-xw hyhs20kmk/ unkby 01fspgr* 9oz)u1(trf 5 $^{\circ} $ C is drawn into a building where it is heated to 25. What will be the relative humidity at this temperature? Assume constant pressure of 1.0 atm. Take into account the expansion of the air.    %

  Estimate the time needed for a glycine molecule (see j-kpo/t ) ug+o0xbd6ltse 2-3jd nt:h, .e fcxTable 13–4) to diffuse a distancel +eue0xnsfg2db- hd.)/p k:,jtc-63tjo otx of 15 $\mu m$ in water at 20$^{\circ} $ C if its concentration varies over that distance from 1 mol/$m^3$ to 0.4 mol/$m^3$ Compare this “speed” to its rms (thermal) speed. The molecular mass of glycine is about 75 u. t $\approx$    s ([color=rgba(0, 0, 0, 0.85)]Round to one decimal places) $v_{diffuse}$    $ \times10^{ -5}$ m/s
$v_{rms}$    m/s

  Oxygen diffuses from the surface of insects to the interior through tiny tube2vwl,tlh )o; ts called tracheae. An averagho ;tlt2)l,v we 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 ber cc9kq qk ruxzc;1c:,7tftr-- cd-r5en 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 beenqc:tys qq;5 ))l zdk myo+55ir 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 norm*x-r1,a.nn ,kljqvhto8 bz1 mal room temperature. How much error will be made in a recipe calling for 300 mL of cool water, if the water and the cup are .r mj kb,*ohan1l-zx8q,v t1nhot, at 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in a helium gas cylinder is initially 28 atm. Af:t7xzqh)o g oyr 0j3*mter many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fr*7g)z hyqotjo0xr3m :action of the original gas remains in the cylinder?   

  Estimate the number of air molecules ijial:+.n. +e i3p dlhjn a room of length 6.5 m, width 3.1 m, and heigj :a+pdiel l .+nh.3jiht 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 fp8nf: rwg7w0 of matter is about one atom per $cm^3$ mainly hydrogen atoms, and the temperature is about 2.7 K. Calculate the rms speed of these hydrogen atoms, and the pressure (in atmospheres).$v_{rms}$ =    m/s    $ \times10^{-22 }$ atm

  The lowest pressure attainable 4tndw/huxs9pegxd 66+ ;;zhm using the best available vacuum techniques is aboue; ;m+tdg9nd6 wuh 4sz/x6hpxt $10^{-12} N/m^2$ 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 +kjn 4b;mf/ +)hkbvu-a bsq7 jwhen 10 m below the surface, to what volume would his lungs expand if he quickly rose to the surface? Is thisnvq4b7)u;kj a fbbh/-+ + mskj advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmosphejq 337tfe 7ygv aag/5h,xobv* re at a speed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this speed correspond to what temperature? (Because of this high temperature, the nose of a space vehicle must be made of special materials; indeed, part of it does vaporize, and this is seen as a bg,5 3 y agv/jt*f7axhqov7e3bright blaze upon reentry.)    K

  The temperature of an ideal gas is increasr.;ft iq8gq;ued 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 o3t8mby 7tfpg*f 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 atmospheric pressure sng( ,wki r*8tfh,w1vat the surface of the Earth, estimate the total number of air molecules in the Eart,v,n w*k8wg(r1 sf hith’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen mol,bf8v b0dql, aecules 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 hospital has gauge pressure = 2000 x,ux ndr+x- tw -w3 .rqtu6vr*psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure,3w-rnxwt.,r qduxr-t u6* x+v is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liquid mercury at z0d unw.l3dhe: k 4hmx;nvp/40$^{\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 gasoli)lt2r( 1u(nkxsubo+ ane at 0$^{\circ} $C is 0.68$ \times10^{3 }kg/m^3$ What is the density on a hot day, when the temperature is 38$^{\circ} $C?    kg/$m^3$
What is the percentage change?    %

  If a steel band were to fit snugly around the Earc 2daii,; j- a:saz 7ko1ef(kfoi5vo0th’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 glasf .dw pm l/ bjk;1ma:3o64ct6ng8acxn s 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 the zlsdrr ox015n 0l) o/l18$^{th}$ 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 fulpq+c9i.- zavd ly charged, has a pressure of 195 atm at 20$^{\circ} $C. The volume of the tank is 11.3 L.
(a) What would the volume of the air be at 1.00 atm and at the same temperature?    L
(b) Before entering the water, a person consumes 2.0 L of air in each breath, and breathes 12 times a minute. At this rate, how long would the tank last?    min
(c) At a depth of 20.0 m of sea water and temperature of 10$^{\circ} $C, how long would the same tank last assuming the breathing rate does not change?    min

  The escape speed from the Eartrq dd+6erpbm009sw9 ih 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 tennk : ke7o tw*k4ki/jxp;is balls thrown vertically upward at 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/skk74je/t p xk:k; ow*i   balls/s

  A scuba diver releases a 3.00-cm-diameter (spherical) bubble of air from a depthcxv t xf8s;h wc5i6/n+ of 14.0 m tnhfcw+xs 5;68icx /v 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 surface?    cm

  Calculate the total water vapor pressure in the air on th9oz kc ab:usu6q2 rbm -u8jf j:rb fucz644d4-e following two days: b r-fc:ju 6m d:bcsj49o -8ruu2kz4f6bq4zau
(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 denw t) b,9 ai-c j2sfhl;crw6y;dksjw/.sity of iron at STP, and when it is a solid deep in the Earth wheyc2/9hr, jwf; l.tdsc-b siakw6j) w;re 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 constant pressurl9ji7q vq vp0ydnx+8oo8/c3 h e, the coefficiei0+ qvodx9cpy83/n h7j8vloqnt 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.