Which has more atoms: 1 kg of iron orqwg yl v:b zo3ky4j7.( ,n(jws 1 kg of aluminum? See the periodic table or Apv3y(z 7bs,o( j :ykwlwgj n.4qpendix B.

Name several propertiesmxvc 3u/ vyra0 ajz0;jg*7,xk of materials that could be exploited to make a thermometer. ,aak /*cj073 grjzu0 vymvx;x

Which is larger, 1 C:lt 1 ry29tk;hn6trzp $^{\circ} $ or 1 F $^{\circ} $?

If system A is in the 5u2q8s/j)ppk.bbeb4) psdyx rmal equilibrium with system B, but B is not in thermal equilibrium with system C, what ca x)pbjs k4upd) .b/ys5qp8b2en you say about the temperatures of A, B, and C?

A flat bimetallic strip consists ofm8kdq(gj7rtzix6, a)dx22l d aluminum riveted to a strip of iron. When heated, the strip will bend,j27qgld z8it6m 2k )xraxd(d. 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 coeff4:f hrryz vcrn*r, 2x/icient of linear expansion $\alpha$ are $(C?)^{-1}$ and there is no mention of a length unit such as meters. Would the expansion coefficient change if we used feet or millimeters instead of meters? Explain.

Figure 13–27 shows a diagram of a simple thermostat used to l( -(byk(n fvdcontrol 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 conv( fky(db-n(l tact wires. Explain how this device controls the furnace and how it can be set at different temperatures.

Long steam pipes that are fixed at the ends often have a section in thedhhv7 xv e:r(jj.cr,.wz *7 jh shape of a j7ch7hrjjd*ev :hvw.x z,r(. U. Why?

A flat, uniform cylind ,v; *;gjof0cog d2a*tvp aj(uer 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 thermome-;i c4nfb/orr iso*( ater is first placed in a hot tub of water, the mercury initially desc-bi/ ( oofrn4*i;s arcends a bit and then rises. Explain.

A glass container may br11iyx5ygt5y1 -p a cqmeak if one part of it is heated or cooled more rapidly than1-cqpi5 tya 1gxy1 ym5 adjacent parts. Explain.

The principal virtue of Pyrex glass is that its q)+rs2j * ygdvbp4 (wvw7kxoob. 7mt- coefficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistanq pby.7 +24jx )w d7gsv-(tvkmwo*bro ce of Pyrex.

Will a grandfather clock, acc)co5f-w;hn3vmmpripulgxfy4f 6 e.n/ao/9 : urate 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 aeh sl(60iuq wl2p*zl8w;(mitnd top to bulge so badly the can will not standu 08wz it;*e wl(l s2lpqim(h6 up. What has happened?

When a gas is rapidly compressed (say, by pushing down a h6h a6j8unr n j m(hnb19t2w3kpiston), its temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperature using the kinetwj3 k6 nm8 hh1rtnb92hj6 (nauic theory, in particular noting what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force on an aluminum sphere submerged in water inc /dfd1g8az4o orease or decrease if the temperature is increased from 20af/ 1g8o4zdod $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theory + n8)ov i7iem: k4. sryyj pbhhb:e ;r(6ttk0zand the relation between average kinetic ener)e hy7tkh4 m.j on6vpb; ir:8r+ybs0: iketz(gy and the absolute temperature.

Explain in words how Gay-Lussac’s law fokkm -lxn2swi,) g,(tn llows from kinetic theory.

As you go higher in the Earth’s at9 +vdfjtr/*c2 c 8otgc3:inktmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to tjur,0 go tg;ty/. yob:he minimum speed an object must have to leave the Earth and never return. The escape velocity for: gtbty;oyoj g.r u/0, the Moon is about one-fifth what it is for the Earth due to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickjw: o 0:)w t9f/cojanx7kqal d6*m 9bcly than water at room temperature. What can you infer about the molecular proper ca/m cown 9:6bftjkoxl0j w7a*: )d9qties of one relative to the other?

Explain why a hot humid dayshu cohc7c 6- 6 g(:ef(gb v2yt/a 4yup+sm/xv is far more uncomfortable than a hot dry day at the s ys:po/tf cbcmv-e(g xvuu6gc4(hy62+ a7/h same temperature.

Is it possible to boil water at rg2jcyc(h.o09/ g9ka: lvwnkb r/j, xpoom temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the humidity vhz 3mmh *m0b5is different. Which is more dense, the dry air om*z m0hm3vh5b r the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap of an overheated automob)xm+zdj b/d pr w5r8*jile e w/pdmdrz b58jx* +r)jngine.

Why does exhaled air appear a-lbk0g3/d uk us a little white cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram copper pefw(tp.r w r ;c.e4+ em0qcn3hknny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare to nk(id bp mp0:;sg8-bzthe number in a silver ring of the same mag bz0ki8n bs dppm;-(:ss?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is thojywx*-khw r81 ym55fis on the Celsius scale?rk8 hm5y1xw-wo5j f* y   $^{\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 recopm.s 1*xkina1rded 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 le wejer4l-.8k lngth 11.82 cm at 0.0e8l.jk-4r ew l $^{\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 lon. tr ymg/bl y0.50v+ess+qlpm z2cfg *g (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 iroz5:so cur e n+0x,-seon approximately 300 m tall. Estimate how much its height changes between July (average temperature of 25°C) and January (average temxue-:+c zs0r se,on5operature 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 large5ax1cf(j g+ mar 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 51mf a+cgaj x(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 4k: dsui1-r h9u-9nz yd $^{\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 h+8zrciia5h31zm8 h b be its change in volume if it is heated frozhr aci8 hb1+ mhz85i3m 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350.0 mL of water at 1xc:*k uro6 +x/h d+4 vdbcwj2f00.0$^{\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 ofbisjlv6 5*he ) 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 j g0s3rik myv 2itb,h, l7/.syin 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 expmg ehkdd32q/ fk1; (xpru*-vband in essentially one direction only, show that the effective coefficient of linear expansion is approxirbekufp1 2 d-hg(q*xdv/km 3;mately equal to the coefficient of volume expansion $\beta$.

(a) Show that the chgkv2sbq66x e2 t-p +x4ayv-(zlp ce q3ange 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 lengthd:gc -c z2 ecdun0b*x9 l and width w has coefficient of linear expansiog0d-ceuzcx2n:9 dc* bn $\alpha$ 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 solidsqcb4 g o /p)5fng+e6t, $\beta$ = 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 and z; 7xaa t32ll- dc5jjhkeeps perfect time at 17 ;-z3 alajt5jh2 cdx7l$^{\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 ihc/ty etkl.8,yboo (ei47,w lnside diameter of 0.140 mm. The bulb has a volume 8. e/ytto(4y blh,kic owl e,7of 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 radius 0.41 m is rotating ab24fdc q(,z.tt h)t s1ez+hu vjout its axle on frictionless bearings with angular velocityq,1 c jfzzdt h2t.th4sue(+v) $\omega$ = 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. How much strese;gjfj)k ;5x xs is required to keep it at this length ;gej5kx) jfx; if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of c5axs q4jzlh02ross-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 2art mtywt-o60 ;5aasy- p br, kysp-,*0$^{\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 temperatx)kn) cck+b.v ures 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 th2 i b x.h6x *+a+uaoucf*ct +zf/whdt(e Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun are abo*sc bk l hekk9ggahe;)a;e7b z1+ i(uyk0v f);ut 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, aiqtm3y ;w.a6qr r at atmospheric pressure and a temperature qa.6yw t3qmr ;of about 20$^{\circ} $C is compressed in the cylinder by a piston to $\frac{1}{9}$ of its original volume (compression ratio = 9.0). Estimate the temperature of the compressed air, assuming the pressure reaches 40 atm.    $^{\circ} $ C

  Calculate the density of oxygen at STP using the ide:hu*wx /)w4m5zie kycal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of nitt py0m96hwz4o 1ys00:sd xyrxk+nc;erogen ($N_2$) 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 contaubelj8 2pp)c-g 9j,r ains 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 gas i1i7 kgy ar78ozd4+j hss 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 czeb+bn(d;o0on 2k .sa9o6e . vve hnz:ontainer holding 105.0 kg of argon gas at 3850k e96. bdnzhvoz(ob nsev.+nao;2 :e K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg.b9vuj5kj )p 5iwvjw 9 of $O_2$ gas at a gauge pressure of 8.70 atm. If the oxygen is replaced by helium, how many kilograms of the latter will be needed to produce a gauge pressure of 7.00 atm?    kg He

  A hot-air balloon achieves its buoyant lift by heating the air int (jc0qpin7kj0qg* 9h5c085jbyl ytoside the balloon, which makes it less dense than the air outside. Suppose the volume of a balloon*y o0kc7b9qcgt0tj0( pyjhn lj q585i 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 15 o2l6 9 qgg9ujmehi3;x$^{\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 tm w7jl :wpvm1,(k+yjru l1z-hl -q)eat 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 esca rr2 )b6rfbvwv:riigw,afnin:* * :y.pes 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 mop 81yn2q7c- vm ;cezbflecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are theretnvf rf kz6g-o 1.1iy7 in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (9iua7xjya533 n anwp+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 f17wbx3 wlhc+dg1ap+- w djgy6w p:l75.1$ \times10^{ -2}m^3$ is filled with air at atmospheric pressure at 20 $^{\circ} $ C. The box is closed and heated to 180 $^{\circ} $ C. What is the net force on each side of the box?    N

  Estimate how many molecules of air are in each 2.0-L breath you inhalre0guqwyqreu9u ,zbq7, z5-0e that were also in the last breath Galileo took. [Hint: Assume the atmosphere is about 10 km high and of const70zweg y09bu -rqu,qqrz u5, eant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic ene jt h b,h7t6d)vlu:6dfrgy of an oxygen molecule at STP?b,:jh6ldv7 th)u f6dt    $ \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 th5 16md+7lbwam c 8ghcke surface of the Sun at a temperatgd8b7m 6c5ach+w1km lure of about 6000 K.    m/s

  By what factor will the rms speed of gas molecules increnyo.s);ykc6f f1 5gbuase if the temperature is increasef u)f5o6b;c gsyn 1yk.d 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 ofz81+v qe0q3ccm c-le t km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, aneecc+zqmqc310 -t l8vd 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at 20sup sjrb+eg n-7o4k85++ yhpj .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 what4a7u x k-k6s femau2oa,:3 ahg factors h24oagexafkkuam:7u6,a 3- does $v_{rms}$ change?   

Show that the rms speed of mol5 tafnki/ek ;ea ths)1tz*-y+ecules 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 same temperature, the0x5z+b sjgvqx; bf66d ratio of their rms speeds is equal to the inverse ratio of the ;sg5x66 jdfbvqzxb0+ square roots of their molecular masses.

  What is the rms speed of nitrogen moltpg ,se 1.nkl)ecules 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 ox8qee pq paqct8h2)527vj 7lq:1rctvkygen 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 distanmw*4rk.kg pi ) a9:xmjce between nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular mass is a8+lqg89bto j8xf,od 89 u in a living cet9f ,laqo8bx+ gjo d88ll at 37 $^{\circ} $ C.    m/s
(b) What would be the rms speed of a protein of molecular mass 50,000 u at 37 $^{\circ} $ C?    m/s

Show that the pressure P of a gas can be written *q*bvu,v*jc-t e+cecP = $\frac(1)(3)\rho v^2$ where $\rho$ is the density of the gas and v is the rms speed of the molecules.

  The two isotopes of ura l szc 424(zclwngd,p,nium, $^{235}$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 p8x txeibk2y5b.. km1fc8acs0hases 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 g-+tekdao;i5d u4c,(cwub qg bsro9dj r(254 is 0.01 atm and the temperature is (a) 54red(q2uw d a(4,+bc9 ug itk ;ogbdc5- rosj90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if 0-x ep80)ic p0vijd0k ht/xuythe humidity is 50% on a day when the temperature is cp)dkx00vxu0i h t8y/ije0p -25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure avqd 2u,xa iujb/u) rzlev+6hd1w+c1 / t a place where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mo uu9bwm.h+8yauntains is 0.72 atm, estimate the temperature a9wuh u8b+ my.at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of wrow ktc4 yb360ater is 530 Pa and the relattby3rw 0ok6c4ive humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure )dgo eiw5nykjw . q 8pth9(5y2of water 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 water ibc6 a*f mv*6n/-wnvqws boiling at a tempe*nc-f wqa nbv6 *w/m6vrature of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room mfc5wx.( : pwaof 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 m) tn0ddz 7 2qzcv-)lqm(8elrpoint of 5 $^{\circ} $ C is drawn into a building where it is heated to 25. What will be the relative humidity at this temperature? Assume constant pressure of 1.0 atm. Take into account the expansion of the air.    %

  Estimate the time needed for j2.djour2c 834heco y a glycine molecule (see Table 13–4) to diffuse a distancejc 2ro8 e3h2 .duoyj4c 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 iti36gb u6drbs+i8c 5interior through tiny tubes called tracheae. An average trachea is about 2 mm long and 3 +68st5uri b6bigdcihas 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 measur*9 x,ktked 0u gmj87nqe 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 calefic0oiy g)3 tx6oy3, ibrated 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 temperaturey2 ;gr e;esg1n6 grvy-. How much error will be made in a recipe calling for 300 mL ofggevy-s;g 21;rn6r e y cool water, if the water and the cup are hot, at 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in a helium ga( a fpm dlltq.oz;x: t86i52mls cylinder is initially 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. What frll(qx2m . 8oz5fmi6tadlt :;paction of the original gas remains in the cylinder?   

  Estimate the number of air molecules in a room of length 6.5 m, width 3 1c)nbhdwbz )7.1 m, and height nw)b7)dbh cz1 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 densitf+u- mpkgpx.6 y of matter is about one atom per $cm^3$ mainly hydrogen atoms, and the temperature is about 2.7 K. Calculate the rms speed of these hydrogen atoms, and the pressure (in atmospheres).$v_{rms}$ =    m/s    $ \times10^{-22 }$ atm

  The lowest pressure attainable using the best available vacuum techniques is abooj(: kg chq0j.rmuk2+rw)7twc8 wq- cut(m q+j 2 :w)cgkrc- j8 krw7toqhwu.c0 $10^{-12} N/m^2$ 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 lung. zvulte:b( 899law hhei9u:4 elepu:* jb7vas to full capacity of 5.5 L when 10 m below the surface, to what volume would his8v.ule l(a7jez :l9ia tuw9 v49:bhhu ep:eb* 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 spee0b+cth cv 3l+s7 rr8*(nl,z tvkbxu3od of about 40,000 km/h Molecules (assu cb3* +3(r8 uvt7bhc l,k0xto+nlzrvsme 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 an ideal gas is increased fp;jdtcdh*9*- wxtk**fvif i 9rom 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 774kszliok dw9 / bx166v0m$^2$ (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 qwc cd+)w qt3. rod1f2the surface of the Earth, estimate the totwdq c r+fd.woct31)q2al number of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contained in a 70: xoiput6o 9l.6$-m^3$ volume at 4.2 atm if the total amount of nitrogen is 1800 mol?    m/s

  A standard cylinder of oxygen r-+4 /:b6, tzhzuww:ffhntn yused in a hospital has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder l:nut,6zh:nz/ -+r w4yfhfwbt ast if the flow rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liquid mercury at 0,* pd-obcybawp /v:/kp0je)sp +n .tm$^{\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 gasolxxsf ql r.) 60sdl76kzine 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 fi(v1mvx 1wg db*pw4 l0pt snugly around the Earth’s equator at 25$^{\circ} $C, but then was heated to 45$^{\circ} $C, how high above the Earth would the band be (assume equal everywhere)?    m

  A brass lid screws tightly onto a glass jar at g ;ljk+lnl3s820$^{\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 stanzvt fn wqm;w1j..14z1e zic-l dard, adopted 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 chargedp btg8rq l,x0uqcryx,r 77eppny./)) , has a pressure of 195 atm at 20$^{\circ} $C. The volume of the tank is 11.3 L.
(a) What would the volume of the air be at 1.00 atm and at the same temperature?    L
(b) Before entering the water, a person consumes 2.0 L of air in each breath, and breathes 12 times a minute. At this rate, how long would the tank last?    min
(c) At a depth of 20.0 m of sea water and temperature of 10$^{\circ} $C, how long would the same tank last assuming the breathing rate does not change?    min

  The escape speed from the Earth i;.k d iipq1xqy8efx z es8c5,y8dn53 os $ 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 ballsk; 8 uo, zlu5qvg91jm4no 7a /zfctrgv+lps;6 thrown vertically upward at it. How many tennis balls per second must rebound from the lid elastically, assuming uu; sj64cr,/qlo9t1 7 pmvk fvn8ga +z5;gz olthey have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter (spherichku b)-) jlw-ez w ;d2en bg)roa90,lral) bubble of air from a depth of 14.0 m in a lake. Assume the tkr2 el9zwl-0bnrbju,a- ge) ))h wdo;emperature 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 p o2)mc-pn qid2ressure in the air on the following two days: ci )pdn2 2o-mq
(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 ir 3 )qcd, q1lukjs;i4,e(rnbb ion at STP, and when it is a solid deep ib )snbkd13q(iieulj ,c rq,; 4n 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 fe3 gwmpm -bu*wr/ g59that, for an ideal gas at constant pressure, the coe 53*mg bfrwwg9m- /eupfficient of volume expansion is equal to $\beta$ = 1/T where T is the temperature in kelvins. Compare to Table 13–1 for gases at T = 293K (b) Show that the bulk modulus (Section 9–5) for an ideal gas held at constant temperature is B = P where P is the pressure.

  In humid climates, people constantly dehumidify their cellars tok iaoy0l/b6giilh.p - h0g8.ts.ez)k prevent rot and -o0k)ebs6y.a8lphk. lz/gih0 i.tg imildew. 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