Which has more atoms: 1 kg of iron or tdn,4oqd. 3fq7brxw +1 kg of aluminum? See the periodic table or Appq47nddf q +. wrxb,ot3endix B.

Name several properties of materials that could be exploited to ma:b se3x8rpva +/4fzc:c pev-pke a thermometer 8fbee-axv z/4prp cp3s+ :v:c.

Which is larger, 1 Clf7 opym ,6.s23c pise t)q7yh $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B is not in the qpxywh2(8*rh c 9ptq)iq5n +wrmal equilibrium with system C,(tr i8yw qpq qhc+h*n2xpw)95 what can you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to a strip of iron. pulc8dkdt7h.)v.z+ve7iw )j ,yop0xWhen heated, the strip will bend. Which metal will be on the outside of the curve? [Hint: See Tedl0o78v)p ujd xtw ,+iz).p7k.hc vy able 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 coefl 1 2tnonq 8r/ruuyy4(c.)z mfficient 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 control a furnace 2rm3)ws2n,: ebrn l1v0pdvao (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together.,2 r3sr wvm 1abvo:ep 2)l0nnd The electric switch is a glass vessel containing liquid mercury that conducts electricity when it can flow to touch both contact wires. Explain how this device controls the furnace and how it can be set at different temperatures.

Long steam pipes that are fixed at the ends often god7jtzr4x9du3r1 p 5have a section in the shape of a U. Whtr3up z dxr7g 14do59jy?

A flat, uniform cylinder of lead floa49 (ag1hqpl aaeny;7 wts 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 huxi ,*vegbs y.7q j-8vot tub of water, the mercq7b8 .sxy ,g- eujivv*ury initially descends a bit and then rises. Explain.

A glass container may break if one part of it is heate6o90yo . xpdp.ctx9jqd or cooled more rapidly than adj69 pqcxtp9j..oo ydx0acent parts. Explain.

The principal virtue of Pyrex glass is that its coefficient of linear expansion 8bm uj wa9+l3q:y)h btis much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pywbtjlm)y8h: 3quba9 +rex.

Will a grandfather clock, acc(. hl: e6+(ycvb;q9zr3d7 y is kujcpburate 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 sosx4wi.h3jz-k d1f8f kk1xl .wda will cause its bottom and top to bulge so badly the can wi kl3 -1h4x fk1zki.wfwxs.dj8 ll not stand up. What has happened?

When a gas is rapidly compressed (say, by pushing down ak fg9d d3kgys.o-7mih 86 s(wx piston), its temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperature using the kinetic theory,-sw hsm idf96 kxgkdg37o .y8( 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 increase or dec-yz*vpqe) b(d rease if the temperatp)e-dz*qb( v yure is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from k*vct80cd-gpe yuy0 w 1inetic theory and the relation betwcv0 -wy0t8y cpeu d1g*een average kinetic energy and the absolute temperature.

Explain in words how Gay-Lussac’s law follows from kinetic 7-7bfitt cu- 1kf 7xththeory.

As you go higher in the Earth’v: eiwpmn/yz/0ru+aht; *iit+ 9l 2xls atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refera sq/;z. d woq.;m4vbfs to the minimum speed an object must have to leawz/;. a sf bmv4do;qq.ve 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 practically no atmosphere.

Alcohol evaporates more quickly than water at room temperature. Whqbl9c;ky 7t1 yat can you infer about the molecular properties of one relative to the othe bc;lqky1 t79yr?

Explain why a hot humid day is far more uncomfortable than a hot dry day at ,gyl*jmivu iw: 6n5v2the same temp,vyj*igm:6i 25v lnuw erature.

Is it possible to boil water at room temperature w eme1bbeb/g goxuzj*;0.9y ((20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but thbcn 5: (x(-xdgqf)emrptc h 86e humidity is different. Which is more dense, the ( :t pr (5fxmh8)qcngxcd6e-bdry air or the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap of an overheeb 98dlbq4 c1cated automobile engine.e bql41bd cc89

Why does exhaled air ap7z) ) ayo*ovn raj/xf;pear as a little white cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.c4ciy, mldy464-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold rine:dq*p; 8nq hqty0t8o g compare to the number in a silver rnyto phe*q8tq: ;q0 8ding of the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What p*a3p4il-esu 0cz vtmx a)/y8 is this on the Celsius scale?4i3e/)mp v uxzc ats*y8p0-al   $^{\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 re)b9gak6 mnz fdf7/+ibcorded 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 11rzwjun*h u 0sal(-g76.82 cm at 0.sa7(gu0j hz-n6urw*l0 $^{\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 long6 y+ee,4:b.idkl i9 pl wiioa. (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 ironw+lbj dn*/ m2h approximately 300 m tall. Estimate how much its height changes between July (average temperature of 25°C) and Jah* jd2 +mnl/wbnuary (average temperature of 2 $^{\circ} $ C). Ignore the angles of the iron beams, and treat the tower as a vertical beam.    m

  To make a secure fit, rivets that are larger than the rivet hole are often 7mu*a s:aj ,uqused and thej*a7u: asmqu , 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 20 $^{\circ} $ C. To what temperature must the rivet be cooled if it is to fit in the hole?    $^{\circ} $ C

  The density of water at 4 u;-8e i b3if;aeko:qf$^{\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 cmc.he;-n8 aefjssbts, *cw4tg-jog2- in diameter. What will be its change in volume if it is hen-h-; 4t2satsbjc. jwe-ef 8sg*co,g ated 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 water at 10tl*vb1;s bx f iapt+8.0.0$^{\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 5j,u;j t0f9 v pxdn)luwater at 20 $^{\circ} $ C completely fills a container to the brim. When the container and the water are heated to 60 $^{\circ} $ C, 0.35 g of water is lost. (a) What is the coefficient of volume expansion of the container?    $ \times10^{-5 }$ /$C^0$(b) What is the most likely material of the container? The density of water at 60°C is 0.98324g/ml.

  (a) A brass plug is to be placed in a ring made of iro*4 ay/lizxsj i; 5ie p**olb+bn. 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 i8u:zj 5 mur3cmn a long, narrow vessel so it can expand in essentially one direction only, show that the effective coefficienr8:zj mu cmu35t of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the densb-quk 9vu6ks egx(*/ i76 g r/yczim-dity $\rho$ 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 widthn+9ovs8v rv .:ls op9j w has coefficient of linear expan .v:+ rj9vso 8ovl9pnssion $\alpha$ 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 isotropicuk43jg) ,lm0 svffl 5i7a8kwd/nkza6 solid, $\beta$ = 3$\alpha$ if the amount of expansion is small. $\beta$ and $\alpha$ are the coefficients of volume and linear expansion, respectively. [Hint: Consider a cubical solid, and neglect very small quantities. See also Problem 18 and Fig. 13–30.]

  The pendulum in a grandfather clock is made ofx6t xeljcu ;+),,afu4 per; wg brass and keeps perfect time at 1xge;,cf ) le4x ,u+;wt6rj pau7 $^{\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 aa0jdc4 0 qfe1su-zx.0.140 mm. The bulb has a volume of 0.25ca0 - 4jq1zx0s.ufeda5 $cm^3$ 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 radiudijbjw ; ,u.p)s 0.41 m is rotating about its axle on frictionleu,;b d)i.pjjw ss bearings with angular velocity $\omega$ = 32.8 rad/s If its temperature is now raised from 20.0 $^{\circ} $ C to 75.0 $^{\circ} $ C, what is the fractional change in $\omega$?   

  An aluminum bar has the desired length when at 15°C. How mu4f6kih s+ 6ai -umvv;jch stress is required to;6mk64sui+jv -vfi ah keep it at this length if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-b hzj7jrled x8xqox8: z: 40jt0eam of cross-sectional area 0.041$m^2$ is rigidly connected to two vertical steel girders. If the beam was installed when the temperature was 30$^{\circ} $ C, what stress is developed in the beam when the temperature drops to -30 $^{\circ} $ C (b) Is the ultimate strength of the steel exceeded? (c) What stress is developed if the beam is concrete and has a cross-sectional area of 0.13$m^2$ Will it fracture?

  A barrel of diameter 134.122 cm rnuo-dpz 1g8y70xx*g at 20$^{\circ} $ C is to be enclosed by an iron band. The circular band has an inside diameter of 134.110 cm at 20$^{\circ} $ C. It is 7.4 cm wide and 0.65 cm thick.
(a) To what temperature must the band be heated so that it will fit over the barrel? $\approx$   $^{\circ} $ C(Round to the nearest integer)
(b) What will be the tension in the band when it cools to 20$^{\circ} $ C?    N

  What are the following temperatures on the Kelvin:;kti ccd )vx,7he 5cp:e5 wtj 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 tet9 e 8b0:eicwemperature on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun are a;s0e02dh lpl sbout 4000$^{\circ} $ C and $ \times10^{6 }$ $^{\circ} $ C respectively.
(a) What are these temperatures in kelvins?    K    $ \times10^{ 6}$K
(b) What percent error is made in each case if a person forgets to change $^{\circ} $ C to K? $\approx$    %(Round to the nearest integer) $\approx$    %(Round to three decimal places)

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

  In an internal combustion engine, air at atmospheric pressure and a temperature g)tv xfvqi2r2j/b p:+of pxvvb+/ 2 r) ig2tj:qfabout 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 ide3r6j/: ykmvedr+o s:bal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of nl ya5c;k)hd3l itrogen ($N_2$) 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 con8 hum+io0up7*fl hd9m tains 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 is at sheoj9 tp.svf4k r89; 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.sma jy(+bnz; 2cscg7 :0 kg of argon gas at 385 K+ 2bayj (g;7csn: mcsz?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg op guo.2 vib yzw3ug7-0c(z4bioi8 zp6f $O_2$ 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 5jx hx5dh1) zcheating the air inside the balloon, which makes it le)c5jdzx hh5x1 ss dense than the air outside. Suppose the volume of a balloon is 1800 $m^3$ and the required lift is 2700 N (rough estimate of the weight of the equipment and passenger). Calculate the temperature of the air inside the balloon which will produce the required lift. Assume that the outside air temperature is 0 $^{\circ} $ C and that air is an ideal gas under these conditions. What factors limit the maximum altitude attainable by this method for a given load? (Neglect variables like wind.) $\approx$    $^{\circ} $ C(Round to the nearest integer)

  A tire is filled wita brtf . d81kfj:jx.7ah 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 at 1 x migfun30q7*sq13.gfg pjy9t5eg3h8.0 $^{\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 j oczr q aaka o;6o+42 i-ppb4;qz/vg-xk7lp+ 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 ofgq0bpnubg r*t m9nscc: n4-78 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? Hod-qmg0o zvtd2*9qvvfr)c -6i w many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) mo) *qrv*izif9k les,    $ \times10^{22 }$ moles and (b) molecules of water in all the Earth’s oceans. Assume water covers 75% of the Earth to an average depth of 3 km. $\approx$    $ \times10^{46 }$ molecules

  A cubic box of volume 5.1unc5 1g0mp; ntvaj*g-$ \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 molejyyz u-gn(sp,:cm.q , cules of air are in each 2.0-L breath you inhale that were also in the last breath Galileo took. [Hint: Assume the atmosphere ,p : q,ymu.csngz(-j yis about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of an obdez+ a5:to h)29mzjoxygen molecule at STP? ed)z mj h2bo5+a9:t oz   $ \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 thewxeemoutya7q3cqv gv7( 2 */5 Sun at a temperature ofmy v v5g37t auec2*q7xe(w/q o about 6000 K.    m/s

  By what factor will the rms speectpw;wwnc(24ho0 o) wk/. aabd of gas molecules increase if the temperature is inckaww o c.p nobt)0/h2;4cwaw(reased 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 spe km w2h09bp,09w: sedkkhvv6v60 ohjpeds, given in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calculate the rmskewh j6p0vkdmhs ,:9h6 pvw9o0b 2v0k speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas .g uhc:kzg77 b)js v3vq) ae/aat 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 itf:p7z*ii y9 uzs volume is held constant, by what factor doz7zi p:iufy*9 es $v_{rms}$ change?   

Show that the rms spee1+tjs9l0 txadi7 g09 cpiszk )d 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 same tb3e7yzbu0( klemperature, the ratio of their rms speeds is equal to the inverse ratio of the square roots of their molecularykleb ( 30b7uz masses.

  What is the rms speed of nitrogen molecuunsj+k 7dw- h3les 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 xw 5/m(h36x o6xgyk xjm26tz ban 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 bek vxak03m21 gk/)+6n (q)cbdal1m 3 gpchgsjxtween nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid,xo5 d*.dorp.kh; xmqoek 3*i whose molecular mass is 89 u in a lio,x mi;qxp o5.kod.* 3 erdk*hving cell at 37 $^{\circ} $ C.    m/s
(b) What would be the rms speed of a protein of molecular mass 50,000 u at 37 $^{\circ} $ C?    m/s

Show that the pressure P of a gas can be written /h/k3i2q1 sx br 2buxhP = $\frac(1)(3)\rho v^2$ where $\rho$ is the density of the gas and v is the rms speed of the molecules.

  The two isotopes of uran;7smvf)4v m vnium, $^{235}$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 whaq+to eaga3zq*2z /9pr t 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 jegeee*/i ,h1zwj8 d1 the pressure is 0.01 atm and the temperature is (a)1e/1,8ieew*z g hjd je 90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (appro bexh1*6 ehow*nr7o3ym0* xpmximately) if the humidity is 50% on a day when the temperature1e* mphox*3 oebw6m 0nyxh*r7 is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at ag*eqmw7nf-6)0g /ur qqljf w/i 4nnxq/(yu b5 place where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is 0.729hj:xbalt8pu (3k r l0 atm, estimate the temperature at which wat arl(tul0:jx 3khp 89ber boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of water is 530 Pa an)l1if )yqo-jyd the riyl1j)qf)y -oelative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure ofh;p3b / d/xbo bc1/x1eg ecd5m 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 tmx5liviiqp-b6 ,: ol 6ibo;; rhe water is boiling at a temperature of 120 5m: il6bii; v,; po bq-lr6xio$^{\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 6kod-d+tlsn3x9d- 6 oo 80$m^3$ at 25 $^{\circ} $ C is 80%, what mass of water can still evaporate from an open pan?    kg

  Air that is at its dew point of mw7+l z9 oc5dck y1f5n5 $^{\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 mvt hjvn 7 cv;.gh;/asog(*9rdmxuj p(w74/ unolecule (see Table 13–4) to diffuse a di;jujumvct9xvnp(7 rw .goa(; d4/vs/hhg *7 nstance 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 s yn7eqc.l mt,8vq-s-yurface of insects to the interior through tiny tubes called tracheae. An average trachea is about 2 mm long and has cross-sectional area mcq,vq8 7yny-l -set.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 mal5fu(a5 m8ne easure 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 caljmm0v2 w+i e3t r 7dhuyf(fd.3ibrated 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 temperx4 u3db1; r y*/ejo2:btiuwa 9ace2daature. How much error will be made in a recipe calling for 300 mL of cool water, if the water and the cup are ho / u ddwbaicb 32a9:4oe eu;ar1y2jxt*t, 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. After ma5 yqe f7r1vhfgurr8n 83x(gf(ny balloons have been blown up, the gauge pressuhf7 y 18fr5ggx8efr( 3v( uqrnre has decreased to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air molecules in a room of length 6.5 m, width 3.1 mie +l3;;n k 3u3 ,dtteui jqu-o5temq), and heigh,ktmle-5qeu;3tji u d3teu qno+i;) 3 t 2.5 m. Assume the temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is about one at1zh0n t5ep0wsom 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 a aiqc4 ko7-b +qgz1/vxvailable vacuum techniques is about g+1 /cvq zkioqa4b 7-x$10^{-12} N/m^2$ 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 t:rq0j+yasi1*ilm ai q0 pld4)o full capacity of 5.5 L when 10 m below the surface, to what voluj*d 0qs 1y:0 +)ai lml4aiiprqme would his lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moon entert:m v56,cg p cwme/qm1s Earth’s atmosphere 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 nc teqw5mpmg:1vc,6 m/ose of a space vehicle must be made of special materials; indeed, part of it does vaporize, and this is seen as a bright blaze upon reentry.)    K

  The temperature of an ideal gas is increased from 11rybk + o23l;6 uev9/sdxsnz7v0$^{\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 7u ze4 5rcp hz,d1 5y:dq5h2fzd70m$^2$ (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 pc0iz.0yok7 zz2 vave- rqye79ressure at the surface of the Earth, estimate the total number of air zy7c ayver 7q k0-0z.eo9z2ivmolecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contained* 0v;wz 55.wbwek , apeqzzk zx,o;:nw 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 g /2xz5k(l h:sxop;lucwgd)r*auge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure, is cons2lr xh;c)*o(d u/ k5sxw:lpzgtant at 2.4 L/min. $\approx$    hour

  An iron cube floats inm ehz+ (y9(gcuoktqo 6d8+-swvr73z r 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 pzdx dxv).,rp/; f,f p2sl urlui5/r, 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 tg 0lazybksr*u m f/+pd2k8 /2qvmwyx *-l-g 2xhe 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 m. fxx .:zk(d9ka2yv +r*m e rw2qiu(ea 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 the 1gsp. o8ve2cq :8$^{th}$ 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 pressurhx7la6w5b zz 0iiw4y8 .tkk z2e 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 fro3alflqnv9w /dok+)f7-w6cfx 5 g tu7km the Earth is $ 1.12\times10^{4 } m/s$ so a gas molecule travelling away from Earth near the outer boundary of the Earth’s atmosphere would, at this speed, be able to escape from the Earth’s gravitational field. At what temperature is the average speed of
(a) oxygen molecules,    $ \times10^{5 }$K
(b) helium atoms equal to $ 1.12\times10^{4 } m/s$    $ \times10^{4}$K
(c) Can you see why our atmosphere contains oxygen but not helium?

  A 1.0-kg trash-can lid is suspendely79d6m6x e mixnn( y;d against gravity by tennis balls thrown vertically upward at it. How many tennis 6e7x(m inxln yd6 m9;yballs per second must rebound from the lid elastically, assuming they have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-c-wmcikc17-6 8 kpxca vm-diameter (spherical) bubble of air from a depth of 14.0 m in a lake. Assume the temperatcc6v-k iac8k-7 xwp1 mure 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 bzu: 25mc i1 xbk70scmvapor pressure in the air on the following two days: bi01 :xucs 5mcbzmk7 2
(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 wpam1krt, /.-iqb7y+ 8axql mv hen it is a solid deep7mr/y1a.alqv+mtbq8 ,-i xpk 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 anu (th78kshxd3 ideal gas at constant pressure, the coefficient of volume expansion is ekx( u 3th7d8hsqual 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.