Which has more atoms: 1 kg of iron orpfkicl :0 b0l-9 b)9 0yq(fgkxjqx5 nw 1 kg of aluminum? See the periodic table or Appendix Bfpqic-:f9k500wjb )0n bly(qxl 9kg x.

Name several properties o9i49j umjts76qx qm4zf materials that could be exploited to make a thermomete9q q6mz49mij47utsj x r.

Which is larger, 1 C 1h5 2nsjsu*lo yu fxfv81c2fj- x3gt -$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal eqb(pwd0rcoqz/5 r(0 x3+t wvry uilibrium with system B, but B is not in thermal equilibrium with system C, what can you say about the tv 0t3(o/pyczw dwbrx05qr(+r emperatures of A, B, and C?

A flat bimetallic strip consists ojh.2zo+aasz tx6z)yv3 :6g ,* qxpcqx f aluminum riveted to a strip of iron. When heated, the strip will bend. Which metal will be on the outside of the curve? [Hint: Shp z36 )sqy x*z.vta62gzo:cqxx aj+,ee 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 coefficient m5 jsqg3 hwz*3br5t msu4nx0sdne70 gq 78)ufof 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 cy tqf c4r1/jx8lp4g(hontrol 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 jpcl xqg/f8 r hty414(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 ajd:z z k4pr *xt6lsg4-t the ends often have a section in the shape of a U. zg jp:4-r xd lts4*6zkWhy?

A flat, uniform cylinder of lea, 4pb x*bmib5ed floats in mercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometer is first plac)xer0 wb9 vo0/izwaz8sco*mlhj9 5w1ed in a hot tub of water, the mm5 za*w1v9i)cxhe8 /9 0ows0wzo lrj bercury initially descends a bit and then rises. Explain.

A glass container may break if one part of it is heated or cool3rw4aq p .o9osed more rapidly than adjacent parts. Explain..o 94pa3qosw r

The principal virtue of Pyrex glass is that its cons(a ;n j 9mg0l-:povdefficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrexmj osnpv9l;0nad(g:- .

Will a grandfather clock, accurate sxqm- *mlkvo*f;. d-mat 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 causrm8j:rilwitxe5zkb d / t yh-4+v*m7(e its bottom and top to bulge so badly the can will not stand up. Whermm-vlx+i8tdk4:*h(w rt i/ j5 7zbyat has happened?

When a gas is rapidly compressed f1c2r88 ew5uqa kapx; (say, by pushing down a piston), its temperature increases. When a gas expands against p28eq15aw k;ura 8fxc a piston, it cools. Explain these changes in temperature using the kinetic 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 submermoa lqef 221/qged in water increase or decreeq o12 /m2aqflase if the temperature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words howswxx);wc+/ du8o*;bx y 5nlxk Charles’s law follows from kinetic theory and the relation between average kinetic enesdnxx w 8;ulxc;yb+x) /o*wk5 rgy and the absolute temperature.

Explain in words how Gay-Lussac’s law follows from kinetic th xg ouv1q,13n5j6rme eeory.

As you go higher in the Earth’s atmosphere, the ratio ;6vai:6bvi( *r nrcyi l(wd :yof $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earthc2 wde1ffany 64rlj4 f70aw4*wld/q f 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 isy2j 47*qafalwdf 041/c6e4 wfwd lfn r for the Earth due to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates mokx 0qv)nb- t9ure quickly than water at room temperature. What can you infer about the moleculxt-0 vnkbqu9 )ar properties of one relative to the other?

Explain why a hot humid day is far more uncomfortable than a hot dry day at tn+er8k qgw9q1o4.f jnhe same temp+ng4 j woe8qqkrnf91.erature.

Is it possible to boil water atzw68 m 24hspsa0sco-d room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperump f-8jjj, -chkp+5fature is the same but the humidity is different. Whichumhj-pfpkj j8fc 5-+, is more dense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap of an overhe c9 nkrv )2cp.;tls,mf9 y9lvhated automobile, ;vmscp.v9nc tfkhyrl9l9 )2 engine.

Why does exhaled air appear as ai wl 2wv3v6s, c.v8fup0isl4 o little white cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4bj5,5jfq sh .k-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26/)od fl-qqg8p.5-gram gold ring compare to the number in a silver ring of the same -df g p/oq)ql8mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this on theybtoa l*15/;g p5qggj Celsius scale?gg1yb5p;jg / ol*qa5t   $^{\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 recorded ar8d5itv h y)(ude 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 ha zb8t +c .fiz(koz+y*zs length 11.82 cm at 0.0+8t* k zobziyzzf(+c . $^{\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 i d-6pvm1igw z/x7fk)a s built of slabs 12 m long (20 $^{\circ} $ C). How wide should the expansion cracks between the slabs be (at 20 $^{\circ} $ C) to prevent buckling if the range of temperature is -30 $^{\circ} $ C to +50 $^{\circ} $ C?    m

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

  The Eiffel Tower (Fig. 13–29) is built of wrought iron app0 nc h63-ele 9auj6taxroximately 300 m tall. Estimate how much its height changes between July (ahne390 -jal6xc t6aeuverage temperature of 25°C) and January (average temperature of 2 $^{\circ} $ C). Ignore the angles of the iron beams, and treat the tower as a vertical beam.    m

  To make a secure fit,g,d oad opyja179 ,.zu rivets that are larger than the rivet hole are often used and the rivet is coold,g 1azyo oa.,9dup7jed (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 a-v-nc 6 p6onwyt 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 lnkdt 6k)+pd/ diameter. What will be its change in volume if it lt/dk+dp6n ) kis heated from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350.0 mL of w(nj:oh71o wxn1 gqp0k5f m kuw0;4lb rater at 100.0$^{\circ} $ C. If the temperature decreased to 20.0 $^{\circ} $ C, how much water could be added to the glass?    mL

  It is observed that 55.50 mL of watex7 ac gj,hn2n2r 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 o/zjsyyc.i 1g9f 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 eer*t :,wbp(by b+epd5xpand in essentially one direction only * :p,b5yber+(wepbdt, show that the effective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change iuh4 rr(g o51z au+gncap3zq..n the density $\rho$ of a substance, when the temperature changes by $\Delta$T is given by $\rho$ = -$\beta$$\rho$$\Delta$T
(b) What is the fractional change in density of a lead sphere whose temperature decreases from 25 $^{\circ} $ C to -40 $^{\circ} $ C？

A uniform rectangular plate of length l and width w has cozs b74es:tclx/): s lfefficient of linear ex/::b7ets xfz llcs4s)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 siund+s7eht tl+ 95io (olid, $\beta$ = 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 is7vj albg t1 nc.zx(1w7 made of brass and keeps perfect time at 17 .(z1xw a7t l1g jcb7vn$^{\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 mercub 3aki( :ai m1ievuuqfv*q* 9rt/r24jry thermometer has an inside diameter of 0.140 mm. The bulb has a9(re 3a:iuq*1f / tv v qrmii4jkbua2* volume of 0.255 $cm^3$ How far will the thread of mercury move when the temperature changes from 11.5 $^{\circ} $ C to 33.0 $^{\circ} $ C? Take into account expansion of the Pyrex glass.    cm(b) Determine a formula for the length of the mercury column in terms of relevant variables. Ignore tube volume compared to bulb volume.

  A 23.4-kg solid aluminum cylindrical wh p/ 10plc- n;jt xjxtm9.p2bsieel of radius 0.41 m is rotating about its axle on frictionless beax/tpj.n0 l1s bjcp-ti ;2xp9mrings 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 much stress is re/x1+l7k l 9shrh 5hvhnquired to keep it at this length if the temperature increases h7rvk +/h5hxl1 nh9slto 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam 4jx r2i(bh wd3of 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 13swmkg 6p,w93+ sd:s sk4.122 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 temperatures on t93pn +jl a0gz7go2ona he 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 Fahr+)5i mixd7zah3j :aklenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun ar7m+pi 6s5,t svyc9s owe 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 enginew3 /1kh+f skywwvnx09+0 un xp, air at atmospheric pressure and a temperature o300 n+9w vys/xwu kx wf+phk1nf 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 um3 5si xze- qpq(7ud0using the ideal gas law.    kg/$m^3$

  A storage tank containb)nql *3urh 6ws 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 contains 1r0qne):uoge3y5 6wif 8.5 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 gb,m 7 mc 56vi4lmcx9ynas 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 yf j /*ue)er0ma 35.0-L container holding 105.0 kg of argon gas at /rm )0*euy fje385 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg ofobxo xxal j6) w5/*kzr9d3x b8 $O_2$ 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 achie6/- as *2 zo5goouk,vpvfp/tzymb76nves its buoyant lift by heating the air inside the balloon, which makes it less-6z/z7bg aov o tmfnpsy/o5v2*p6k,u 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 with f,lelx t -:kex 03o v2weq)s6pair 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 ato 3k4a09dih0bqdc.nt 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 escapes59skdml,1dps-q ,j a6)fzja tbhww98 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 oeqz)x99udbs/e4n8*z 2(m sb0 d kiblof 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? How man h5 .hrd8 gaf3q,zf inm*sza+6y molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) mt;yxgg0(9he h oles,    $ \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 5.14p44xjb.yajv $ \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 moleculev*60wuk3 ncir uip4d5 s of air are in each 2.0-L breath you inhale that were also in the last breath Galileo took. [Hint: Assume the atp 50icnwrv3k*u 6iu4d mosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of an oxygeng0c6 wfvpo y0 -pes2qps -zy x4r910zo molecule at STPvs-p y9rz wpoxz160pc2seg 0qy 40 o-f?    $ \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 o-cqzxn3d z 7j+f helium atoms near the surface of the Sun at a temperatu+7q zjd x-nc3zre of about 6000 K.    m/s

  By what factor will th+u mzpv; n.ax0 r v)7tcro5guu 49l4nye rms speed of gas molecules increase if the temperature is .x p4+5vunm ant) uu v09cl;yrgo47 rzincreased from 0 $^{\circ} $ C to 100 $^{\circ} $ C?   

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

  Twelve molecules have the following speeds, given in units of km/sdoa)vx6x,s9ty(t r )l : 6, 2, 4, 6, 0, 4, 1, 8,ottx69srv (d)ya)l x , 5, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at 20;qrewm ov8 df ;z*v7mm3zh0p (.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 7 vxy,s orw85nis held constant, by what facton 8rv7 5swxy,or does $v_{rms}$ change?   

Show that the rms speu lq0ei73w ;died 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 temperature, the ratio27lxds8hr :yp2aim 4ac*h/ee of their rms speeds is equa8ex mda:s* hhyr42le2 p7/ca il to the inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen lnzd79f ,gldd;gb.ke *fg- x* molecules contained in an 8.5$-m^3$ volume at 2.1 atm if the total amount of nitrogen is 1300 mol?    m/s

  Calculate (a) the rms speed of an oxy3aqn gki49 rg0gen 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 betweewgyez 4be5+x;a gs /b0n nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecula xqwpuubk o+78hl-c *+o6op;or mass is 89 u in a living cell at b-wk8*oc xu ;7qo6h +oplpu+o37 $^{\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 writtenl7jg0fh 0cd+w 2d; fqo P = $\frac(1)(3)\rho v^2$ where $\rho$ is the density of the gas and v is the rms speed of the molecules.

  The two isotopes of uranium,j0dmfd;2 d)i qu. 2erj $^{235}$U and $^{238}$U (the superscripts refer to their atomic mass), can be separated by a gas-diffusion process by combining them with fluorine to make the gaseous compound UF$_6$ Calculate the ratio of the rms speeds of these molecules for the two isotopes, at constant T.   

(a) At atmospheric pressure, in what phases can j 1.2ybp xz,/neytlu,$CO_2$ 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 pfb a;jmjgmx34r i6x3rg 5ad7jk 0gc +/ressure is 0.01 atm and the temperature is (a) 9 6gg; cdri a33f5rjm0g bxjm/4k+xja70 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity is 50% on a dayb00*ko,lb18i g gwsg v when the temper 0g1vi,bg bs0 wl*8gkoature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at 0vtcd0ch4q n, srb0v /a place where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular pl4 a1esow/egh )ace in the mountains is 0.72 atm, estimate the temperatgws 1oeh 4a/)eure at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of wat,r/sl.2qdm*8vbp)kwym) n l ber is 530 Pa and the relative huvlbrq*yw2pmk )b8d mn .sl)/ ,midity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the temperatum6pwp c 3pi(ju6(8btire is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cooker if the water is boilin n4/yg- zad*i3j/thh) w uyp9gg at a temperature of 4ytjh /3*pizwu yha )- n9ggd/120 $^{\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 67w,x 7 4ts deo+i-half80$m^3$ 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 lughtse 7e+q 2ut1wtg i-493d 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 nee1n9 4jqhivt* q h+epzo8b+s:vded for a glycine molecule (see Table 13–4) to diffuse a distaoi 4hh qjvvqpeb*9s8++ :t n1znce 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 trfk03869l)+caqas u ncdi+p n o the interior through tiny tubes called tracheae. An average trachea is about 2 mm long and has cria 80ld 6 cfcprqnk)+3sn+au9oss-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 o )7e,x1bohyz 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 cabd2 tk.b)m 6sghg/ 1rm(tp+exlibrated 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 4 jg ra- ocov7hg+f5 ya9+mih3normal room temperature. How much error wilojr-o y+4 73ihgg9aha+vcm 5fl be made in a recipe calling for 300 mL of 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 gas cylinderk5 +)2t3xdvt dhv mhn2m5 79 zgqmsjs0 is initially 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fractiot0v25 d79tnmqh g+hvxzk s5dm)sm2 3jn 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 bmm e;pd.qt8/y us(w6m, and height 2.5 m. Assume the temperature8sytq;.pw(mb/ud 6e m is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the dens jv nm)7vb06 f,fsztr0ity 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 attaina/)mwn/r -etcx ble using the best available vacuum techniques is about )- e/nwx/m trc$10^{-12} N/m^2$ At such a pressure, how many molecules are there per $cm^3$ at 0$^{\circ} $C?    $\frac{molecules}{cm^3}$

  If a scuba diver fills his lungs to full capacity of 5.5 L when 10 mg+u bvo 1u3o5zcron/ : /d,qe/e+ih sa below the surface, to what volume would his lungs expand if he quickly rose to the su//gv soh z:35e/e,aqurnb 1dco+iu+o rface? Is this advisable?    L

  A space vehicle returning from the 5ss*ycp td wfd)s3)yl /1m/ btMoon enters Earth’s atmosphere at a speed of about 40,000 km/h Molecules (assume nitrogen) striking the 3/*b/pc)fy) wdl1yst ds5stmnose 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 fromy7 3zej :obz6u 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 + bwz1py+hnmj0zs (o3 of 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 atm7/9oq3z,j y;ygun okxospheric pressure at the surface of the Earth, estimate the total number of air molecules in the Earth’s y,u zy3j qx;/go9kon7atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitr .--zd2 s3ztbx+2beyh 6jdt hcogen molecules contained in a 7.6$-m^3$ volume at 4.2 atm if the total amount of nitrogen is 1800 mol?    m/s

  A standard cylinder of oxygen used in a hospital has gkpps( 0blt qabz.(2e1auge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rat2 1a( s(ekqlbbz.p0p te, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liqui hudvk7 fsc 839b2qy9yd 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 at mkci / )th-))zr9dpnnke 0+tp 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 Earth’s equatorycgl bf t1j 4c6(yb-e/ 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 ontobtk(o8b2fu0 i a glass jar at 20$^{\circ} $C. To help open the jar, it can be placed into a bath of hot water. After this treatment, the temperatures of the lid and the jar are both 60$^{\circ} $C. The inside diameter of the lid is 8.0 cm at 20$^{\circ} $C. Find the size of the gap (difference in radius) that develops by this procedure.    cm

  The first length standard,p: rcd8u /.usvz1 vh,t 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 charged, has a pressure of 195 a :q8,jz5ey(h7/ v xlbdsnh c(ntm 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 fromnuo6+;* kyvafil0ihro r3. v,s w/r)t 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 suspended against grq;ktqb87k zq )bgh45g avity by tennis balls thrown vertically upward at it. How many tennis balls per second must rebound from the lid eq gh48 qk5k;bg)b qz7tlastically, assuming they have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter (spherical) bubble of air from a:vm jiese msm1:/lm )g9km9 j* depth of 14.0 m in a lake. Asm9 1 mej/j)i::* ksv9me mlgsmsume 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 the following two dauz8v0+gjeio clx( )2zys: ie)(vuj+zxo0 g2zcl8
(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 differencekfgb*ihaxpm/az/m ;1dd2 +g + in the density of iron at STP, and when it is a solid deep in the Earth where the temperature is +mdk2 1ag bid/p*gma/+;zx fh2000$^{\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 f:fyj7ni-c17 sw 4yd/f t:bq(oubu5t show that, for an ideal gas at constant pressure, the coefficient of volume expansion is equ 4 o5 cdftutsjwyyfq(7n17bf:b-: /uial 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 to preventj a0a,e3vtg(w rot and mildew. If the cellar in a house (kept a0a(av 3j,get wt 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