Which has more atoms: 1 kg of iron or 1 kg o8la;.zk8l2umg fi *dx qp -lcgl7y2n7f aluminum? See the periodic table or Appenldnfl kl*u7 gz8mxpa igq c22 y78;-.ldix B.

Name several properties of mqjd(p(x/ul* 2lzeg; zmkv8v 6aterials that could be exploited to make a thermometl(m kzlz62 peqxvd( 8j;v u*/ger.

Which is larger, 1 Ce,p:2t. - naul4pxmgi $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium wia h,gb 9eyl z*je., t:nf6if*oth system B, but B is not in thermal equilibrium with system C, what can you sayhjn**f:9.,iz b,ea l 6feogyt about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to a strly g5.ya ngk0b bu17i0ip of iron. When heated, the strip will bend. Which metal will be on the outside of the curve? [Hint: See Table 13k0b1y. b0ugngy i75la–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 linear expansionnbq 7 ib.+a 2rc/kr;ow $\alpha$ 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 diawf+7m3y xdop1pgx 44egram of a simple thermostat used to control a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch is a glass vessel containing liquid mercury that conducts electricity when it can flow to touch both contact wires. Explain how this device controls the furnace and how it can be set at differe37myd1ofpegw x +4 px4nt temperatures.

Long steam pipes that are fixed at the ends often have a section in t/uce oi 66xs ;l1c3mbmfyog, )he shape of a U.e,b guo cfy3)moc6;s/ 6li mx1 Why?

A flat, uniform cylinder of leu,e2abx p izp:fp3 c/:ad 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 placed in a hot tub of water, 3u*q8opa5rdu c 1gb3opeu/o,c x *ja2the uox2*poab1u 3jrp,uag5/ ecd8*q o3cmercury initially descends a bit and then rises. Explain.

A glass container may break if one part of it is heated or coole gwz4;/, oti ahx xl/y)fdh (v+a.s(dhd more rapidly than adjacent paz(ot+xhx, fy4;v)a( /ws ihh d/l. gadrts. Explain.

The principal virtue of Pyrex glass is fxhrrx9 zbz6q ,ze ki)72+ yg.xcq:d5that its coefficient of linear expansion is much smalk ygxzh, 5ce)q+r.xd2ixbrzqz9f 76 : ler than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accgx cxi5bc dc). c9/t2v gic/1furate 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 wi9pk/b;- w mqdg3--e bhmkten4ll cause its bottom and top to bulge so badly the can will not stand up. W-g ;pbe/4 e3wbtnh-md-mkq 9 khat has happened?

When a gas is rapidly compressed (say, by pushing down a piston), ib7uv ajtme5 u /d5u4+lts temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperature using the kinetic theory, in particular noting what happens to the momentum of molecules whe5du 5u4t jvme7+a/b lun they strike the moving piston.

Will the buoyant force on an alpuv8( ibfrc37 ,l,(apw mex)w uminum sphere submerged in water increase or decrease if the te(w)xrp vleiwp c3 ,b 7u,a8f(mmperature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s lag/9fnri;g4fl w follows from kinetic theory and the relation between average kinetic energy ffgl i;4 n9/grand the absolute temperature.

Explain in words how Gay-Lussac’s law follows from ** ivo la ks0xp4eoyu52jb6 8khk(8stkinetic theory.

As you go higher in the Earth’s atmosph kk)t:pmwmpx7+5 k6jpi6 qv/ tvdm,(eere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Ey2(ier8c n;qfarth refers to the minimum speed an object must have to leave the Earth and never return.;c(q8 f nryi2e 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 rua7rz 6;hew3moom temperature. What can you infer about the molecular properties of one relative to the r3ah ;ewu 76mzother?

Explain why a hot humid day is far more uncomfortable than a hot dfj5rif85 r)wswmwbeg- 3 zyl/:n(gb: ry day at the same temg/mbjsw53 :5by8:ei rw-glwn rz( ff )perature.

Is it possible to boil ;1o9i1yuwp /nx, xufbg6b4.rf8j . n*kcvl nhwater at room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the humidit- ttbnl(yj+ no: u0ak9y is different. Which is more dense, the dry air or the humt- jnulb9not 0a+k y(:id air at the same T? Explain.

Explain why it is dangerous to open the radiator pu)z7o gu9x+t cap of an overheated automobile x+)ptzg7u 9ouengine.

Why does exhaled air appear as a litts do1(, boz*kmle white cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-86n *qw d 90mh7dpmhavgram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare to the number in /a yoiz7tfxf s 2 ehhiuvj*6;8y0,ke +a silver ring of the same i0+x6 /u sk;zfe7yyf*vo h ha ,2teij8mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this on the Celsiu6w b:s9po b/res scale? b swp:or/e96b   $^{\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 loweshual2. n) 5emct temperatures recorded are 136 $^{\circ} $F in the Libyan desert and -129 $^{\circ} $F in Antarctica. What are these temperatures on the Celsius scale?high =    $^{\circ} $ C
low =    $^{\circ} $ C

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

  In an alcohol-in-glass thermometer, the alcohol column hasq b9jyt*1udb0xg6 (vd length 11.82 cm at 0.1 j6bg*dxv9 dqyub(t 00 $^{\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 bu+ ve; (zb4 (ry3s3mrr8nx zytuilt 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. 16m huoh5-s+q rgp3 s,u3–29) is built of wrought iron approximately 300 m tall. Estimate how much its height changes between Julyuu o3 ,gsrp6+ q-smh5h (average 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 fithe0sl 4kz )f q8cfb:2x, rivets that are larger than the rivet hole are often used and the rivet is cooled (usually in dry ice) before it is placed in the hole. A steel rivet 1.871 cm in diameter is to be placed ifkh8lqc2 fsx 4b:0)zen 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 , 9vx b9sv5dc4kojmsfl9 b1. w4 $^{\circ} $ C is $ 1\times10^{3 }kg/m^3$ What is water’s density at 94 $^{\circ} $ C?    kg/$m^3$

  A quartz sphere is 8.75 cm in diameter. What will be its cxp 78*/:izkh.//,fy vj5ajr n ogjncp hange in volume if it i:y,*oi /8.p/g nrj / 5nhpjfkc7 zajxvs heated from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled xij5..mbci4qo p:mj 7 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 7p+ni qjd7hebaceoe,kh1*l-:d c9 e9 water at 20 $^{\circ} $ C completely fills a container to the brim. When the container and the water are heated to 60 $^{\circ} $ C, 0.35 g of water is lost. (a) What is the coefficient of volume expansion of the container?    $ \times10^{-5 }$ /$C^0$(b) What is the most likely material of the container? The density of water at 60°C is 0.98324g/ml.

  (a) A brass plug is to be plg:tc6k/,s3i2 szvws.hao n k ,aced in a ring made of iron. At 20 $^{\circ} $ C, the diameter of the plug is 8.753 cm and that of the inside of the ring is 8.743 cm. They must both be brought to what common temperature in order to fit?    $^{\circ} $ C
(b) What if the plug were iron and the ring brass?    $^{\circ} $ C

If a fluid is contained i8ho8r fa1mq0wn a long, narrow vessel so it can expand in essentially one direction only, show that the effective coefficient of linear expanso80 8m1hrqw afion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change invhl7rs ,to)*g ti1n2 iaw6av4 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 of7qn/xd,0 uzuv;) am ukr2bw+u length l and width w has coefficient of linear expansion )/dnx2uumqr+u;,7ba wu0z vk$\alpha$ 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 isotroqdxg xt3 ,k*+ep0lf ( /k:rmfmpic 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,p.2jck7qd lz keeps perfect time at 17 djc.7z, 2qlkp $^{\circ} $ C. How much time is gained or lost in a year if the clock is kept at 25 $^{\circ} $ C? (Assume the frequency dependence on length for a simple pendulum applies.)$\approx$    min(Round to the nearest integer)

  (a) The tube of a mercury thermometer has an inside diameter of 0 bz +,fn4,yxas.140 mm. The bulb hafnyzs,b ,4+xas 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 aluminum cylindrical whee8n .,rvux1dznl of radius 0.41 m is rotating about its x1 .r8n vudnz,axle on frictionless 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 w vsx8k/yr.y n/rac( 3desired length when at 15°C. How much stress is required to keep it at this lenx.nyw/c8kvyr3 a/( s rgth if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of sh+*tlgnd rt/er8n9 x nj48,cq t iz03cross-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 atuz)ir(x xoq5k,ejirp* dt7lc2v) 1y4 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 Kelvk/4- xn)q4w t9rnoplvin 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 Fahrenheie.o6mgs nreeq19h0js;9tz3i -gy v o9t scale?    $^{\circ} $ F

  Typical temperatures in tqs )9 .rxmb)oyhe interior of the Earth and Sun are about 4000$^{\circ} $ C and $ \times10^{6 }$ $^{\circ} $ C respectively.
(a) What are these temperatures in kelvins?    K    $ \times10^{ 6}$K
(b) What percent error is made in each case if a person forgets to change $^{\circ} $ C to K? $\approx$    %(Round to the nearest integer) $\approx$    %(Round to three decimal places)

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

  In an internal combustion engmd7ct-oguds 8 r3h (:bine, air at atmospheric pressure and a temperature of aboutr :gbout87 hmdc(sd- 3 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 ide7.1dszka (q jvdpv ,q5:b6m opal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of nitrogibvqi.ep+ +f1c; d4j f*r vuo :jts*n5en ($N_2$) 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 5fmogl2mkythr,s- : / 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 53d.nmbp6sbgwpm4 wexmx +6 q7m:0klis 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 g1ruxjipry-/5 s81m-q b k+mja 35.0-L container holding 105.0 kg of argon gas at 3851sk+mmgp5 jx rbji/1qu-8y r- K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg oj/4,7 ju,i/y2 pr4zno 4 frf**h mvg3edge fidf $O_2$ gas at a gauge pressure of 8.70 atm. If the oxygen is replaced by helium, how many kilograms of the latter will be needed to produce a gauge pressure of 7.00 atm?    kg He

  A hot-air balloon achieves its buoyant lift by heating the air mow3,o,i7;rpr k q sh:inside the balloon, which makes it less dense than the air outside. Suppose theoowqs,r;, :k3ri 7p mh 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 air at 1i0 t0kr7-uu4wk dkj5l5 $^{\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:drj6eipcggs c / (78ah +ma+ 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’s hand at sea level and 2iqpod(4x n 1lh4n wo*z; b:a b8ibg/u30.0 $^{\circ} $ C. When it reaches an altitude of 3000 m, where the temperature is 5.0 $^{\circ} $ C and the pressure is only 0.70 atm, how will its volume compare to that at sea level?    times the original volume

  Calculate the number of molepxe /4egues p:+/ us9ecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are t4iqy0t ;8bxbtk8h pw5here in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of v p1qjm 6to,:i-z:hx; uc9 zut(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 volumem q:dz zxwk9p.r67lc4 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 are0alf 7ygd /vdp)dd 1e7 in each 2.0-L breath you inhale that were also in the last breath Galileo took. [Hint: Assume the atmosphere is about 10 km high and of constantaed 7l 7pg/d)1dyf 0vd density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic enerufpw m6zm ga)+5) )j p(un-ynkgy of an oxygen molecule at STnp6wy( +)zgu )n m5 uamfpkj)-P?    $ \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 surn1-yn ..t+ 1ezcvo*hngwp .vvqpqe2(face of the Sun at a temperature of about twq*+n o. .c2qn-(pgz1h pe.ev v y1nv6000 K.    m/s

  By what factor will the rms speed ofw0ulde) ec i* q-j (,q8zuhes5 gas molecules increase if the temperature is increased fze0 eeq,( 8idl uhu5csq) -w*jrom 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 ftw26 qos .grc*ollowing speeds, given in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calcswo.6 2tq rg*culate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecul9n,njq7g t( 0ju ohas :1+a,h.ykqag hes in a gas at 20.0 $^{\circ} $ C is to be increased by 1.0%. To what temperature must it be raised?    $^{\circ} $ C

  If the pressure of a gas is doublep;3vx vsacdj3a rb6+ -d while its volume is held constant, by what factor does ca ;+ 3psvjbd6r3x-va $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is;2z5ctxny s t. 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 gaqfxw0 t53/ hzwses at the same temperature, the ratio of their rms speeds is equal to the inverse ratio of the squarwhtzx 0q/ 53wfe roots of their molecular masses.

  What is the rms speed ofjn-3xe98tp 1mtce n8f nitrogen 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 ofgs3ugymyql59,3t;s3 xmu 9 dc 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 distance between nitrogen molecules at S 72s py8:wug4w yxdb)kc81e utTP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular mass i4.(vt)uaezds uj +,po s 89 u in a living cellvej,(dpatu. u4 +s z)o 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 afalkia8.k- o ) 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 (.(dvm0sfl mck :15l j7td ihkuranium, $^{235}$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 cm/ re1d ne qhp y0sw2lrxgwxq 2b-)))4an $CO_2$ exist? (b) For what range of pressures and temperatures can $CO_2$ be a liquid? Refer to Fig. 13–21.

Water is in which phase when the pressure is 0.01 atm and the tyyk9oewr9, md( 9lpyei-,y qac 9(1ozemperature is (a) 90ypw9kcao 91y-9(q i9orm ye,eyl, dz( $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity is 50% on a day when z;lyil2 a r6-zo. yl:ithe temperature isz 6loza.yryl i:-li2; 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure x6ly(u0i n) v:zlu1fa at a place where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure atgsi2f p.uvs4 dhx33 7j a particular place in the mountains is 0.72 atm, estimate the temperature a3gj suih3 d.s4 vpx27ft which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature kze0m )f5mqj)6lq ib s; ak4;son a day when the partial pressure of water is 530 Pa and the ejl4s;65q makqi ;bzmk)0)fsrelative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the temperature is 25 6q18zs 3alkrv $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate p2vcynqqex.dmy9:le 3y h45c;ressure inside a pressure cooker if the water is boiling at ac edvq2.y;e9cq y mx4 n5y3:lh temperature of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a roomnvsg3.9aa ji(- du6soaxa 3v. 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 point j,jn8 +fk +elpof 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 mo86j -aq;winkqe i*fa3lecule (see Table 13–4) to diffuse a distance of 15 aq3iea * ;8j-i6 fqwkn$\mu m$ 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 themj+c yaxk m8b(ev8- x)ls+q9f interior through tiny tubes called tracheae. An average trachea is about 2 mm long asal+cmy98-x mxvqefj +(b8 )k nd has cross-sectional area of $ 2\times10^{-9 } m^2$ Assuming the concentration of oxygen inside is half what it is outside in the atmosphere,
(a) show that the concentration of oxygen in the air (assume 21% is oxygen) at 20$^{\circ} $ C is about 8.7 mol/$m^3$ then $\approx$    mol/$m^3$(Round to one decimal places)
(b) calculate the diffusion rate J,    $ \times10^{-11 }$ mol/s
(c) estimate the average time for a molecule to diffuse in. Assume the diffusion constant is $ 1\times10^{-5 } m^2/s$    s

  A precise steel tape measure has been calibrated v,0-6skkbzwqe 0mur+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 havvyfqs1zbx 8g7ay a 1,.; 8jcus 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 a) vvs*h2bvn.3i /l x8nwdem3-lvha (temperature. How much error will be made in a recipe calling for 300 mL of cool water, if the water 8ha xv-nlb.v ai2dv/n e w3mh)(*3lsvand 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 gzszl 4o d* fn8wsak()0d/o go2as cylinder is initially 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of the origi 8oznd)s zskol*( afdw2/og04nal gas remains in the cylinder?   

  Estimate the number of air mouym, prsk t,w syhh);)yrk22 -lecules in a room of length 6.5 m, width 3.1 m, and height 2.5 m. Assum) myyk )ukh22sw- r,,shprty;e the temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matte,lbp ioa;u),dr is about one atom per $cm^3$ mainly hydrogen atoms, and the temperature is about 2.7 K. Calculate the rms speed of these hydrogen atoms, and the pressure (in atmospheres).$v_{rms}$ =    m/s    $ \times10^{-22 }$ atm

  The lowest pressure attainable using the best available vacuum techni6,ahd;y2,53bft ekuahf fx9g ques is abou 5;9hu6afd,2f,xbfegahkt3 yt $10^{-12} N/m^2$ 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 fullreg9 n08+ ufu0jreo 6vyzu2e3 capacity of 5.5 L when 10 m below the surface, to what volume would his l0ver uy 0uefun orj29+38 ez6gungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from d o:qjp9mk1 2z7 vjz0pzd*uy)the Moon 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? (Bec2:z jz djz0 ovyd71umpqp*k 9)ause 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 from .jegxrr 50ui3110$^{\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 k/l;pppg6e(qk ,, aokm l a6d9770m$^2$ (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 3o.yhwd t1zuu5y s.-ithe surface of the Earth, estimate the total number of air .zuy.3wuo-yih5ds 1t molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contained 5grs+u1 )efhutc t9 v- l4r3 qh9v02dzwm/zsgin 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 prvs2yk6v/sbfa,;ky 8f,xe0;jzom -as essure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure, is constant at 2;;sv8-ayjf2fesb vxo, m a/ ykk6z,0s.4 L/min. $\approx$    hour

  An iron cube floats in a bowl ;d7hvcrlxllp(; 1-j ma.di +ljn7w1dof 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 aswj) 7fq;d8hhlexln.4ecu o-k :k/ :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 t9k 7xdumv7ei8t+gdtgih*4ll 7l vv(: he Earth’s equator at 25$^{\circ} $C, but then was heated to 45$^{\circ} $C, how high above the Earth would the band be (assume equal everywhere)?    m

  A brass lid screws tightly onto a gla-/z,gj (x6tax5qxyr l ss 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 qe)+w/gy0 tr dthe 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 fulla6 9rxj8q i9cry charged, has a pressure of 195 atm at 20$^{\circ} $C. The volume of the tank is 11.3 L.
(a) What would the volume of the air be at 1.00 atm and at the same temperature?    L
(b) Before entering the water, a person consumes 2.0 L of air in each breath, and breathes 12 times a minute. At this rate, how long would the tank last?    min
(c) At a depth of 20.0 m of sea water and temperature of 10$^{\circ} $C, how long would the same tank last assuming the breathing rate does not change?    min

  The escape speed from the Earth is ghw zg+c,u +6h$ 1.12\times10^{4 } m/s$ so a gas molecule travelling away from Earth near the outer boundary of the Earth’s atmosphere would, at this speed, be able to escape from the Earth’s gravitational field. At what temperature is the average speed of
(a) oxygen molecules,    $ \times10^{5 }$K
(b) helium atoms equal to $ 1.12\times10^{4 } m/s$    $ \times10^{4}$K
(c) Can you see why our atmosphere contains oxygen but not helium?

  A 1.0-kg trash-can lid is suspended against gravity byw ,dg*bh,(keg tennis balls thrown vertically upward at it. How many tennis balls per second must rebound from the lid elastically, assuming they have a mass of 0.060 kg and are throw*gehk,(d, bg wn at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diame:a 4th .kdk) fy,unsz(i;c; ilter (spherical) bubble of air from a depth of 14.0 m in a lake. Assume the temperatur;t(c k,izduna;y4fk: si).h le 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 followinb +k2xnus*z7 p4 luc;va)4auq7p/alc g two days: /v a)7l 7qa44b*xunp;2p skcaz+lcuu
(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 5dapq:2 2xbl git is a solid deep in qbg2:ld a5px2the 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 an ideal gas at constar,zm 4xp z8 8;xafiadia2iv u)7 4w-eqnt pressure, the coef8e mfr 42)i-7w;uqzx48dixvai za ,apficient of volume expansion is equal to $\beta$ = 1/T where T is the temperature in kelvins. Compare to Table 13–1 for gases at T = 293K (b) Show that the bulk modulus (Section 9–5) for an ideal gas held at constant temperature is B = P where P is the pressure.

  In humid climates, people consiopcl ry. k(-m;k(st9 tantly dehumidify their cellars to prevent rot and mildew. If the cellar i((mkck -pil r .;tsyo9n a house (kept at 20$^{\circ} $C) has 95 $m^2$ of floor space and a ceiling height of 2.8 m, what is the mass of water that must be removed from it to drop the humidity from 95% to a more reasonable 30%?    kg