Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodic tabh2k+ t884iebj 6n d oonfi2yj 7o:7linle or Appendi87lo2je:tb 6ni8i+innh o oykf4 jd 27x B.

Name several properties of materials that ct3.k 1 9mbrad:ehy h-n6f.tjzould be exploited to make a thermometerk 1 3hbfd.y6a:z.trj-h men9t.

Which is larger, 1 Cjc6u+l.; x xaesr7:v s $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B is not in thd adtod4i/ay)a4)+ fa ermal equilibrium with system C, what can you say about the temperatures )/a 4t+ fdiaay)dd oa4of A, B, and C?

A flat bimetallic strip consists of aluminum rive3:zgy vgvx ma6xtm089ted to a strip of iron. When heated, the strip will bend. Which metal will be on the outside ofgm:a3t x zvvx9my8 6g0 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 coefficient of lin/r*oakp2c)a 1l :q,shfqbaw ,ear 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 conteoh+wcm inxo; cj-.4vv xo68ri+ z:2urol a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch is a glass vessel containing liquid mercury that conducts electricity when it can flow to touch both contact wire+r+. wocz26jeimo o:nc v4uxhxi8;-v s. 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 s1 (v em+4i;kreqhlc(ou/5zzaection in the shape of a ;l5(hv 4zmz er ke+qiacou(/1 U. Why?

A flat, uniform cylinder of lead floats p:cqf ;p, od.7w+hov qin mercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glassjluiz4l,l;k 0:4(b(o kkgd* ppq o(zt thermometer is first placed in a hot tub of water, the mercury initially descends a bit :k 4blkl4pziqd*okp0(;z ul t(gj o,(and then rises. Explain.

A glass container may break if one part of it l0mhguu;s9q 6-a 1i5m td k/elis heated or cooled more rapidly than adjk9g;q tu/ hm0m l6slue1 dai-5acent parts. Explain.

The principal virtue of Pyrex glass is that its coefficient of linear expansio3sfc;ek3 np; on is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrenk3 3 cs;;fopex.

Will a grandfather clockqga.edbrar ql-8 x0+qr/ 00za , accurate at 20 $^{\circ} $ C, run fast or slow on a hot day (30 $^{\circ} $ C)? Explain. The clock uses a pendulum supported on a long, thin brass rod.

Freezing a can of soda will 57 utbi rlfz)re7* k6scause its bottom and top to bulge so badly the can will not sta65 r7krf)ute z lbis*7nd up. What has happened?

When a gas is rapidly compressed (say, by pushing4 z) t6f oz01nuz;kltx down a piston), its temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperature using the kinetic theory, in partictzz) zuxnl6 k4 o;ft10ular noting what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force on an afyk 27 a0sjwaha8h5a9mue1;3 h hj2ogluminum sphere submerged in water increase or decrease if the temperature imu71 93fha yo;805g2aajj hwehkh a2ss increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theory and the relation lw8cw3kco7qsxo0on ):6j ) pybetween average)lco:7 w)qpo6yw03xok cnj8s kinetic energy and the absolute temperature.

Explain in words how Gay0lc fk oof*+.m-Lussac’s law follows from kinetic theory.

As you go higher in the Earth’s aek*kuc.+vgp /tmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed an object must h,8gjdm , 7sbalave to leav,lg baj7md,s8 e 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. Wa k2mz/t, 8n5z3i eocphat can you infer about the molecular properties of one relative to the z8oi/m5a c2 n,z3ptekother?

Explain why a hot humid day is far more uncomfortable than a hot d 818i8e7v: qcfvie eldry day at the same t7v8ic1i8e feqed8 v:lemperature.

Is it possible to boil water at room tempg :ffo.ulxx 54erature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the humidity ov :l +yg/9w)8aqbk wpis different. Which is more dense, the dry air or the humid lk/8w+ y: avq)p9 wbgoair at the same T? Explain.

Explain why it is dangerous to open thehx364w 06.lfhsqo8g a wawl 2ej v)b6o radiator cap of an overheated automobile engin3s2lgwa0ja 8w6v.o)xoh 64qbw6 efhle.

Why does exhaled air aim2z3(1 l q9u8vexnosppear as a little white cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-fczkvy;3b9z l/ d 32z(;dsxlm gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare to theub 5 mzu;a- 3g;jore(i number in a silver ring of the sam bzj5u;moaeu(3rg-; i e mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68 h6e g-9usjn8u°F. What is this on the Celsius scale?6g -u8s nj9ueh   $^{\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 temperature8.0joyu a9dmzs recorded are 136 $^{\circ} $F in the Libyan desert and -129 $^{\circ} $F in Antarctica. What are these temperatures on the Celsius scale?high =    $^{\circ} $ C
low =    $^{\circ} $ C

  (a) 15 $^{\circ} $ below zero on the Celsius scale is what Fahrenheit temperature?    $^{\circ} $ F
(b) 15 $^{\circ} $ below zero on the Fahrenheit scale is what Celsius temperature?   $^{\circ} $ C

  In an alcohol-in-glass thermomet da1/str:6fhper, the alcohol column has length 11.82 cm at 0.:/a6 t frh1psd0 $^{\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 n, xs6 ,j/r5u;i/uoma 3qts phtd)o2 im 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 wt -/zuubtw,2u rought iron approximately 300 m tall. Estimate how much its height changes between July (average t,uz- t/u2t bwuemperature of 25°C) and January (average temperature of 2 $^{\circ} $ C). Ignore the angles of the iron beams, and treat the tower as a vertical beam.    m

  To make a secure fit, rivets th/g*7jjzryn +x at are larger than the rivet hole are often used and the rivet is cooled (usually in7 n*r g+j/xzyj 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 +yx/al pd1mnp)6tp ( o$^{\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 lus6 ss3cb; j0)rx d0gcm in diameter. What will be its change in volume if it is heated from 3;r0 jscbdlsg )u0 3x6s0 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is fil15gdeee- eghc/n4k g .led to the brim with 350.0 mL of water at 100.0$^{\circ} $ C. If the temperature decreased to 20.0 $^{\circ} $ C, how much water could be added to the glass?    mL

  It is observed that 55.50 mL of water at ny i30 /7ugqgdvsc+ t5lq1n; (om vv,d20 $^{\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 mao5 +no mmrk48fgbg*e*de 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 q/d.ghag+5j n can expand in essentially dhj+n. ga/ g5qone direction only, show that the effective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the chann7v c+ h3lwd+sv6 ngo1ge 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 length l and width w has coefficient of linearki9sry7.2dwc r*0h( (1 -zezhdtft xv expan( c (skxr*h9z d2tr7z.1eiv yhtfdw-0sion $\alpha$ 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 isotropiwf vlk5/cq9 a)c 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 of brass and ke:g*zttayq*b7 6 hoy3,n, i1ff gif y3eeps perfect time at 17inft,qoyz, h63f** y1g:et fi3ya b7g $^{\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 diametetbf7k0j/b tc-k e4+zm r of 0.140 mm. The bul cj0 k7z 4b+tt-mfe/bkb has a volume of 0.255 $cm^3$ How far will the thread of mercury move when the temperature changes from 11.5 $^{\circ} $ C to 33.0 $^{\circ} $ C? Take into account expansion of the Pyrex glass.    cm(b) Determine a formula for the length of the mercury column in terms of relevant variables. Ignore tube volume compared to bulb volume.

  A 23.4-kg solid aluminu1 xqtgo5ob-x: m cylindrical wheel of radius 0.41 m is rotating about its axle on frict5 ob1og:x -qxtionless 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 mb,x;l + s;mylvuch stress is required to keepl;vlxb m+ y,;s it at this length if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel xo6v9u1ex imtuni, 2qfy;(y +I-beam 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 134.12uuc2yf v :ciqj.w hl9,r5;k;i 2 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 the Kelvin scale:9;sr-j ,.p14fykwi e;at o+i (sm(epzfrj u7p
(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 oxullzhmw0uh1 , /j27laxj , 0ie eiyjy2. l+3xn the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the intoti +794 ed-n j)rfyeq(p1y8yv vmwb( erior of the Earth and Sun are about 4000$^{\circ} $ C and $ \times10^{6 }$ $^{\circ} $ C respectively.
(a) What are these temperatures in kelvins?    K    $ \times10^{ 6}$K
(b) What percent error is made in each case if a person forgets to change $^{\circ} $ C to K? $\approx$    %(Round to the nearest integer) $\approx$    %(Round to three decimal places)

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

  In an internal combustio+. d6m;5iq drb b0nrotn engine, air at atmospheric pressure and a temperature of a o rb.tq5nd+d 0im;br6bout 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 using0r0(kt ,lq hpf the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of nitrjn fdx;3a b8q)ogen ($N_2$) 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 cont2 drxx5ig5d /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 heli,oo: m(odlnxu( *tmi (um gas is at 10.0$^{\circ} $C and a gauge pressure of 0.350 atm, (a) calculate the volume of the helium gas under these conditions.    $m^3$
(b) Calculate the temperature if the gas is compressed to precisely half the volume at a gauge pressure of 1.00 atm.    $^{\circ} $ C

  What is the pressure inside a 35.0-L coftdo3k2+)vdsp1tr- khvu 00+0q fthmntainer holding 105.0 kg of argon gas at 385 K2t0khkvo)trdmq0 pu+ v sf-d3t+ f01h?   $ \times10^{ 8}$Pa

  A tank contains 26.0 k,cza fhyl5a. vl-yz7 l/p45log 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 bu3rovm *ek/ +iaoyant lift by heating the air inside the balloon, which makes it less dense than the air outside. Suppose the volumeira omvk3/e+* 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 air e -/m3 qo9shru xb;i9lat 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 xmdu9 me7/ji:h/ b9weat 18.0 $^{\circ} $ C and an absolute pressure of 2.45 atm are compressed to 48.8 L and at the same time the temperature is raised to 50.0°C, what will the new pressure be?    atm

  A helium-filled balloon escapes a child’sahrg39x)a-(i31 ye vxh4xyo b 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 f:dw -jdu (ih9k-twq+ao)o,x of molecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.00e4/k5sunbkb wp 4-u s;0 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number + exvsd(;+2afq12vn(utlnfn of (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 voluml 9 uc/;pdf)2 ckyku1re 5.1$ \times10^{ -2}m^3$ is filled with air at atmospheric pressure at 20 $^{\circ} $ C. The box is closed and heated to 180 $^{\circ} $ C. What is the net force on each side of the box?    N

  Estimate how many molecules of air are in each 2.0-L breath you inhaw*l,c ) usopd v/c*sn.le that were also in the last breath Galileo took. [Hint: Assume the atmosphere is about 1 o, ds)*pucnw/clsv.*0 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic enb/mw+-b(vdvs ergy of an oxygen molecule at STP? -db/+ (smbvwv   $ \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 llh)13 gmi+i mrdug(. the Sun at a temperature of about 61di)liu ggr+3 hmm(l.000 K.    m/s

  By what factor will the rx iay0/nkpx:m6(b v948(hmw kp yjy9 rms speed of gas molecules increase if the temperature ink8( b y6/ imw49 0pkmxa9vp:rxyhyj(s increased from 0 $^{\circ} $ C to 100 $^{\circ} $ C?   

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

  Twelve molecules have the following speeds, given in units of km/s: 6, 2, 4, 6,c2wk5rn:8ge3mh+zov77us( l b+rcp a yiun ,1 0, 4, 1, 8, 5, 3, 7, and 8. Calculate the rms 7zv g n w7u15s:+yahr8+cpeicunmr k, b 2ol(3speed. $v_{rms}$ =    km/s

  The rms speed of molecules inoayhqx5rr37 44kf k-fze+lb9 a gas at 20.0 $^{\circ} $ C is to be increased by 1.0%. To what temperature must it be raised?    $^{\circ} $ C

  If the pressure of a gas is doubled while its volume is held constant, by wha7tkukq,zw o2yp v y-),t factor d z,touk)yv2w 7p-,q ykoes $v_{rms}$ change?   

Show that the rms speed of molecules in a q4i i3k4qy kh l2v1v0hgas 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 ol+b*ad7p g58a0syzyz f two gases at the same temperature, the ratio of their rms speeds is equal tblzz5d+7a 8p0yag * yso the inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen molecules contaz -d,d/ 5tcsmbined 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 ni9 i/ r6sd4kaspeed of an oxygen molecule at 0 $^{\circ} $ C    m/s
(b) determine how many times per second it would move back and forth across a 7.0-m-long room on the average, assuming it made very few collisions with other molecules.    round trips per sec

  What is the average distanccs2 ujim7i9p 16eb3dce between nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose moi ab0282msu2ah:f kfelecular mass is 89 u in a living cell at 3 aub28f2fea0i k :2shm7 $^{\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 0s q vd:6orvez2y,gs6 of a gas can be written P = $\frac(1)(3)\rho v^2$ where $\rho$ is the density of the gas and v is the rms speed of the molecules.

  The two isotopes of uyb5k5roxl-hf+ jf( )wranium, $^{235}$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 pht 5*rhoap84ip ases 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 phasg916othx:r:z6mo xpe 9 3cgb qe when the pressure is 0.01 atm and the temperature is (a)g m xqrhc16 z:ep6oob 9xt:g93 90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity 9sz 6ub.gsgn) 6 54zrph1gvt)l et)mf is 50% on a day when the temperature is 46 g 5t1hz9epr) u )fv6g)smgztbsl.n 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place 4tzfp 4 k q znu65xn:z;5a7wrmwhere water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountay6kl1c+dju1v o 7v6rftug.t 6 ins is 0.72 atm, estimate the temperature at which water boils6uygo f+71.1rk6cdv ul6jtvt. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of wz1d 4o;vv/tpxater is 530 Pa and thd; tpv14x/ vzoe relative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when tv nb97vey jr*(he temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure insixqhx9ln 2b0 )ns5c d+5tne 9sn +mm)zhde a pressure cooker if the water is boiling at a temp cz5n0+xn) nmt+b qeld) m9n25xs9shherature of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a ro(,wc *)zpugpwo8k8q bl-mq7e vqh)56y b p0hb om of volume 680$m^3$ at 25 $^{\circ} $ C is 80%, what mass of water can still evaporate from an open pan?    kg

  Air that is at its dew poiq5ql200n1ud fu0iulq hqc 05gnt 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 a glycine molecule (see Table 13–4) to diffuse a dfk3tu*dj qjo; 2o9 qk*istance ;fk2jo*9u qkjto* dq3 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 interiohbgf;zhe/dcbpa8p)f: / 1(d reu(l;g r through tiny tubes called tracheae. An average trachea is about 2 mm long and has cross-sectional area /ghddeplgrbf8 c(a1( fepuz):b;;/h of $ 2\times10^{-9 } m^2$ Assuming the concentration of oxygen inside is half what it is outside in the atmosphere,
(a) show that the concentration of oxygen in the air (assume 21% is oxygen) at 20$^{\circ} $ C is about 8.7 mol/$m^3$ then $\approx$    mol/$m^3$(Round to one decimal places)
(b) calculate the diffusion rate J,    $ \times10^{-11 }$ mol/s
(c) estimate the average time for a molecule to diffuse in. Assume the diffusion constant is $ 1\times10^{-5 } m^2/s$    s

  A precise steel tape measure has been calibrat/z bhnk0brbnl90 ( gppw s9r4)7zt8m ted 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 b3a v g ()e75eb8.qryo6gas cxhas been calibrated at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A Pyrex measuring cup was calibrated at normal room temperature. How much errorvh.yb gc, md:; will be made in a recipe calling for 300 mL ; b:,yhmg v.cdof 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 x)z04u fap:-lz 8 way(ewvoh2a helium gas cylinder is initially 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of 2f0x4e(8y)alaw- zwu:z p ohvthe original gas remains in the cylinder?   

  Estimate the number njw78nm a8q-2z u1jeiuz lpeve8 2*i(of air molecules in a room of length 6.5 m, width 3.1 m, and height 2.5 m. Aiz eaqzu-e7pl uienjv (82* 12j8n wm8ssume 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 aboufun/ a-cu 9e0it 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 availabocc-2 tlvf e p9i2md,4le vacuum techniques is abou c i2ompf, e-2lc94tvdt $10^{-12} N/m^2$ 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 capa6eb 6ys,jvn0yg s.3kx city of 5.5 L when 10 m below the surface, to what volume would hi,. x6yyvs0sbn6 ek3g js lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Mzd*ga8 ug;:-fqhwtze*,r * n uoon enters 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 nose of a space vehicle mu*:z nfr d* -,agh zqw*egu8;tust 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 a0wdsu euk smgm-ej-n8 9c85+is increased from 110$^{\circ} $C to 360$^{\circ} $C while the volume and the number of moles stay constant. By what factor does the pressure change? By what factor does $v_{rms}$ change?$\frac{P_2}{P_1}$ =    $\frac{(v_{rms})_2}{(v_{rms})_1}$ =   

  A house has a volume of 770lut s9: yf,d+br 1mlnr( /t/djm$^2$ (a) What is the total mass of air inside the house at 20$^{\circ} $C?    kg
(b) If the temperature drops to -10$^{\circ} $C what mass of air enters or leaves the house?    kg

  From the known value of atmospheric pressure at the surface of the Earth, estimam mp8+1vix.w ite the total number of air molecules in the Earth’s a8iw1p. xim+vm tmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecuhr.vp lr q3i6wa 7zw7 7eknj41les contained in a 7.6$-m^3$ volume at 4.2 atm if the total amount of nitrogen is 1800 mol?    m/s

  A standard cylinder of oxygen used in a hospital has gauge pressure = 2000 ps ps-i,4o.f gj1k j,yqzgh6puw)fd7 x/i (13,800 kP,jxip-ghf u7g) p1q sw4jod yzf/6 ,k.a) and at T = 259K How long will the cylinder last 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 j. z5xkwj;tv8 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 gasolint(qy rw8pat3on 23em. ov0yd ,e 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 wz7xulgw9(d sb1rft klub.:)1 pn:.j 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 ti/e9h;th(5q, .ld vhdd tvt )zyghtly onto 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, aeh tk-9:rolhto ,/h; qdopted 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 preqazx1mf8a )g vs ko6.dd8,n;dssure 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 thel.yqkqacro(( ;q()no 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 suspens1/ )-va d b9 chsb2pcy4k7aynded against gravity by tennis balls thrown vertically upward at it. How many tennis balls per second mvs1nacb 297 acy )b-4phk/ ysdust 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-cm-dyp,rhxtochs*gays8+; /a; k1iameter (spherical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the air behaves as a perfect gas. How l;y1o hxy,s;r*c a+aksp/ g8htarge is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure i8)hvu y/l :bi*sgvf2in the air on the following two days: ib: 8hiy) v/us2 vflg*
(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 when it is kxw ojwxe9,x2om.tn 7v+q ++ja solid deep in the Earth where the temperature is 2002wtex.vox7j+mxo+nkq9 w j , +0$^{\circ} $C and under 5000 atm of pressure. Assume the bulk modulus (90$\times 10^9N/m^2$) and the coefficient of volume expansion do not vary with temperature and are the same as at STP.    %  ----待选择----decreaseincrease 

(a) Use the ideal gas law to show that, for an ideal gas at constan q6g */gt+y k) jej2m(plrose5t pressure, the coefficient of volume expansiosqy6 glm()/ok+j eegjp*5r2 t n 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.