Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the perix pdy8w* n;cz2odic table or A; z8cw n*ydxp2ppendix B.

Name several properties of materials that could be exploited tvaesj uoh+k ft85ekv4 ) +xp(:o make a thermometer:ua)pjv(of8s k4hx+ k5evte+ .

Which is larger, 1 C ml ,r5 nmq9j7d$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium witjlo/td5 /vvp n+ kv//ah system B, but B is not in thermal equilibrium with system C, what can you svdj+ n/5lvovp/ kat/ /ay about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to a strip : .vl:couwl2q of iron. When heated, the strip will bend. Which metaw ::.qoc2lvul l will be on the outside of the curve? [Hint: See Table 13–1.] Why?

In the relation $\Delta$L = $\alpha$ $L_0$ $\Delta$T, should $L_0$ be the initial length, the final length, or does it matter? Explain.

The units for the coefficient ot 9 au*j1ashx7dl.6zof 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 27ajcer)huh35 r3jtx 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 contrj) u3r hta57 cx3e2jhrols the furnace and how it can be set at different temperatures.

Long steam pipes that are fixed at v9gfl4sejlx u qble*)m: vp65fr)3l,the ends often have a section in the shape oflem gsfll:vbu ,p v*35flj6 )) eq4xr9 a U. Why?

A flat, uniform cylinder of lead floats in mercur ekff 8ls9lb :g) hm*/,y;hpaty 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 f. uisu00k ed v2djp0j2irst placed in a hot tub of water, the mercury initially descends a bit and then .0vdep20 u2uskd ijj 0rises. Explain.

A glass container may br0)di8ganza m .eak if one part of it is heated or cooled more rapidly thi )dzgn0.a8aman adjacent parts. Explain.

The principal virtue of Pyrex glass is that its coefficient of linear ez(-18 zzxqj)x.rkbizxpansion is much smaller than thaz xzrqzzj(1i-x)b.8 kt for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurate at 20+y2mbm5pymu*m j, zq 0 $^{\circ} $ C, run fast or slow on a hot day (30 $^{\circ} $ C)? Explain. The clock uses a pendulum supported on a long, thin brass rod.

Freezing a can of soda will cause nn;ixi4/imjte 1 -5ce+z) zag its bottom and top to bulge so badly the can will not s5neg -inime1 txjiz/;za c+ )4tand up. What has happened?

When a gas is rapidly comp r)gmp)c buqgn8r4; e,ressed (say, by pushing 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 particular noting what happens to the momentum of molecules wbuc;r)r m )4g,qn8ge phen they strike the moving piston.

Will the buoyant forcnjnj)n7 8 ctw;3 fqr,je on an aluminum sphere submerged in water increase or decrease if the temperwrq jn7;)f3 t nj,jcn8ature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theory and the relatkm:5,* iag;(zlkmlkt ion between average kinetic energy and the absolute temperatu zkla;k5 glmt:m(ik,* re.

Explain in words how Gay-Lussac’s law follows from kinetic theouka-g8jamk;) o 6gea3ry.

As you go higher in the Earth’sup y94fx vyt15 atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refer* wodk/7n1fex2 jowi,*jl g d2s 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 is for th1jk7gxo2w j**,fn de li/wo2 de 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. What k3-t+ xcz ie* qdqk1i(can you infer about the molecuzte 3ki*x-i(qk+ q dc1lar properties of one relative to the other?

Explain why a hot humid day is far more uncomfortable thany9y (dz 8b-k;(oux tog a hot dry day at the s ;bug9o yxko(zt8-y(dame temperature.

Is it possible to boil water at room temperatw(3k.: z6zjoxo*mjzqcktd i w x/fi.e44(v ;oure (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when thec)dxk7 :vi.pgbca0s f/kd 0b8 air temperature is the same but the humidity is different. Which is more dense, the dr dv0pbkd k:7s /.0gaxc8ifc)by air or the humid air at the same T? Explain.

Explain why it is dangerous to open ts;iffa/6h z a4xvn8ym;: m6f yhe radiator cap of an overheated automobile e/z y i8;m4xmyhaf s6;fvf:na6ngine.

Why does exhaled air appear as a little white cloud in the winte-4e. dophoav (r (Fig. 13–28)?

  How many atoms are there in af-3 kl dm9,cuq/x8ulj 3.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare t.)ouvml g;xub9 bab y+o; f:a3o the number in a silver ring of the samg v;.a:lo9byboab ; muf3) +uxe mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this on the Celsius scal5)-u pk:zk8qfx7m96zytdqv ne?yqzqp d57k9:-zv fk)xmu86t n   $^{\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 lovxo5vurj9io e ,1: h7bwest 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 has length 11.82 cm a(14cyl+nw/-4xu ;btqqt maod t 0.lbty+w(d-4tn x a4q;u1c /om q0 $^{\circ} $ C and length 22.85 cm at 100.0 $^{\circ} $ C. What is the temperature if the column has length
(a) 16.70 cm,    $^{\circ} $ C
(b) 20.50 cm?    $^{\circ} $ C

  A concrete highway is built of slabs 12 m long (6fk2v epm9 pb:g zet0420 $^{\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. hv1 5o) hp,mk :wp3xgl13–29) is built of wrought iron approximately 300 m tall. Estimate how much its height changes between July (a3 lv5 )khgx,hmp:w1p overage 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, rivets that are larger than the rivet y:*pya34 libp:h vd. rhole are often used and the rivet is cooled.:pay*l4h d vpib :ry3 (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 x6ik, b*ywm5t at 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 8.7syhl exi0 5vxpth6y 2,92*+ dm8 nlztc5 cm in diameter. What will be its change in volume if it is heated f2x5ymztdn60etl9 h8 2v+*x licpshy ,rom 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350.0 mLztc5qha * +s.:u ezo8e 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 of0*/n7nsigzi7-g xpq f water at 20 $^{\circ} $ C completely fills a container to the brim. When the container and the water are heated to 60 $^{\circ} $ C, 0.35 g of water is lost. (a) What is the coefficient of volume expansion of the container?    $ \times10^{-5 }$ /$C^0$(b) What is the most likely material of the container? The density of water at 60°C is 0.98324g/ml.

  (a) A brass plug is to be placed in a ring made o7s, pq ttg, g7sbqfi;/me)e)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 4jdkge) 4xrhi-y 4qakn - at+6long, narrow vessel so it can expand in essentially one direction only, show that the effective coefficient of 4)qek--d+rjha4a6xyi g tkn 4 linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the d, -2mj :oxlc++sac qkeensity $\rho$ 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 rsi0hp2g(-lk19 krbul t 20oo 6adnm* linear exp- donu0kr21(gtl029*b s6l mh oiakrp ansion $\alpha$ 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 isotropi.ct)8vtl yrk9 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 kywum ,6p8src. eeps perfect time at 17 ycsr.6,p u8mw $^{\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 me (0z6j)r)ide1 u/lkqf9yx ckdrcury thermometer has an inside diameter of 0.140 mm. The bulb has a volume of 0.2y1(90)dq )/clek6 kfz drxuij55 $cm^3$ 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 cyl-5emhk/5b myi(kq ii *indrical wheel of radius 0.41 m is rotating about its axle on frictionless bearings with angular viy /eb-( qi* khmik55melocity $\omega$ = 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 lengtdfl3m dke 0a6o 66sv-zh when at 15°C. How much stress is required to keep it ateadf-6kmv lz3o606d s this length if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cr;0jegfwd ,m+(kwm ds :oss-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 atcf z-;lwko82i q;1b st 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 Kelwg b wi05nq( 6pkw*/vsvin 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 tem;cnx/mdwl 4 5-uyq4 :ha wju8fperature on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the intet-.u uzgi,bv clu 0zi.kd,9*brior 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 engine, air at atmo- n u5jex0 80n6o5d b;u5p juh-lthbhdspheric pressure and a temperature o;h-b-5n 5j608 hu0e uud5odntxl jpbhf 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 usinokpl give p d/p19d5c6 n9s).ng the ideal gas law.    kg/$m^3$

  A storage tank contains 6gb-w 5zg6cax 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 jiz7* dhv6dr- s:+ q-m9tk zfwcontains 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 , ) itezwg85apis 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 35.0h65//x7sg.zj sqzmqi -L container holding 105.0 kg of argon gas at / zq56/hzqjximg. 7ss385 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kl69k 7,zv* ktn+uvxg dg of $O_2$ gas at a gauge pressure of 8.70 atm. If the oxygen is replaced by helium, how many kilograms of the latter will be needed to produce a gauge pressure of 7.00 atm?    kg He

  A hot-air balloon achieves its buoyant lift by heating th.5j)drh ooy (ge air inside the balloon, which makes it less dense than the air outside. Suppose the volume of a balloon is 1800 y(d 5gor)h.oj $m^3$ 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 witsqotfh +4h t*5-s3aum h air at 15 $^{\circ} $ C to a gauge pressure of 220 kPa. If the tire reaches a temperature of 38 $^{\circ} $ C, what fraction of the original air must be removed if the original pressure of 220 kPa is to be maintained?    %

  If 61.5 L of oxygen at 1yu1ti f-xz*mm*0s jnu:uf tsii+:umvnf 624:8.0 $^{\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 sebmk oh2)emzym7-14 fo a level and 20.0 $^{\circ} $ C. When it reaches an altitude of 3000 m, where the temperature is 5.0 $^{\circ} $ C and the pressure is only 0.70 atm, how will its volume compare to that at sea level?    times the original volume

  Calculate the number of molecule k+k3s7 zi,hyn jfj3*js / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How many molecule d;ap(5 uggio9s?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) moles, c;py+9n:iqa b   $ \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. +j 2qn0 msjobhl+vg/ljvn3*- 1 tapv*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 molvis4jc9u- ;ll43w wkkjw io8 s)tt 4;qecules of air are in each 2.0-L breath you inhale that were also in the4q)o-ilc 4ks wwv;;3lu k894ti jwtjs last breath Galileo took. [Hint: Assume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of an oxygen mddo:ln u9,q e6olecule at STP u6do:ed, nql9?    $ \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 spees-fqu kl 3+w,od of helium atoms near the surface of the Sun at a temperature of abou3s,- +lw qfukot 6000 K.    m/s

  By what factor will the rms speed of gas molec 6j:(6xxbxfdkf:jg c 6ules increase if the temperature is increased from 6 x66xcfj :gf(d bxk:j0 $^{\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, gi m 9th3d5aot7wu m:rge)z7,mp ven in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 3 7m moh5apgm t:, t9zwr)ued77, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at 20.0 (uystj-:r8f++w b6 savnft;y $^{\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 helzvfq6jx unr ;iee47a3p0we 45 d constant, by what factf ;veq 430x zui6np 4r5e7wajeor does $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is giu+m*tusos1z uuo ;65 7omymo 4ven 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 rit*bnft9br zr .o66co 4 hnirzt+0c8 5atio of their rms speeds is equal to the inverse ratio of the i6t90zo 6+rroir4cbz*.fnttn h8b5csquare roots of their molecular masses.

  What is the rms speed of nitrogen moleculeu7bbfj1 aq 6 hr/i -m*iqtr3h3s 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 oxyge 8sfeh9a gw.t7fll5/ zn 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 nmg(c2bqj6-m distance between nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular mass i 67 t+sasoe5 z.lk0:o2mhqb tts 89 u in a living cellto +bstm :l2 h75okq6ats. e0z 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 Pddcn0z 7q3cncnt4g8 z ;b.)sk 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 uran1c6afg c 0d s*o9g.fndeb6q*qium, $^{235}$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 caa: q/ugugv3 )*hw,+uxhh pz *)h;tnjk n $CO_2$ 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 ajy fs,xtz8d2pg5q0 r:tu6w-ntm and the temperature is (a) sx,-pdq5t gu zw8yn06 r2t:fj 90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point 1-s6 lq diqug.;tu+wh(approximately) if the humidity is 50% on a day when the temperature ihqi 1l;.-6wd uq+utgss 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where vd.) ywl )jkd1vsute 091 ph3bwater boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is 0.72 atml(y q .7up rh7a1ueq9k, estimate the te(ku.7qp9rhlqu a7 ye 1mperature at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of water is ap56q uk: m1,g.re;i kw;jxux530 Pa and the re6kwqp 1,u jur.amgi 5;x:;exklative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressur(.*og:g q6*li rfjwc me of water on a day when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cof)7 yd(p/ks;j tmykhau 4z: ,eoker if the water is boiling at a temperature of 120 ukd(,7 jha4fmk z:/py se);yt$^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a, 8ktfla/ph4m15 k; 6mx)hcpvjf 5iur room 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 of 3.,z-c 6wacwnsr6yxf t hridlwgfnd l8*./ 605 $^{\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 d )y dwo1zhyscx1w481ti8w) 1 xoht4dywyc1s1zstance 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 int gcuph+z+,x +kot1ic 2erior through tiny tubes called tracheae. An average trachea is abouc1g,cux+ +izh+2potkt 2 mm long and 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 calibratga9w+-k fnw5.cmd2s tr c 6*yged 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 6m.vp 4b6 bu* mo 0 we)jo/sf)4dfqzodbeen 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 rv j,vk w t5m wl19;fs;r; kw,z2jy8nzzmq)ey0oom temperature. How much error will be made in a recipe calling for 300 mL of cool water, if the water and the cup are h5t,z;k szqen0jjmmf,;vy)w z klyrw 91 ;2wv8ot, at 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in a helium gas cylinder is initially 2 p9(7bbm4s nulo9o6uv 8 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of the original gas remains in the cylinderu l6sb4 om9(n7p vobu9?   

  Estimate the number of airv:i6xpploke2f0 j -5 v72jcgx molecules in a room of length 6.5 m, width 3.1 m, and height 2.5 m. Assume thejej2kvg05 x ci po76xv- flp:2 temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is awbn./ t8bnq y5bout 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 vac1teilj/ ;y6n6 dgzm qzi6.u5t uum techniques is abozyt liz6n du.tj/6g;em1 i6q5ut $10^{-12} N/m^2$ 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 fulke6 m kcwj70:zl capacity of 5.5 L when 10 m below the surface, to w0 k7kj6emzwc :hat volume would his lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmosphere at a speed of pjk,nry (1 rj(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 must be made of special materials; indeed, part of it does vaporize, and this is seen as a bright blaze upon reentrjp(j(ky1r,nr y.)    K

  The temperature of an ideal gas is increased from 11c7kqirz-e*r. k :w4 rp0$^{\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(bzs(0c)gk kfjng 99tr8v f*yz y2)1od q ax7z 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 atmospheric pressure at the suvufh3os gl9d;oh* 8 /erface of the Earth, estimate the total number of air moleculu*89 h;o/ vldsfh3 ogees in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contained ip*i.g00h t lwln 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 gaugi95usj s f:tu)(a qqbf8o +,xre pressure = 2000 psi (13,800 kPa) and at T = 259K How long wiuf s: s8t rxobq9,i5 ua+jfq)(ll 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 liw jxsz0+m. aql eacy(81(/asgquid 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 0/lfrchkc9 5b xic;d ,($^{\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 ne94r -9,vku+piybr vquyk .)5sz 9tgequator 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 glam 1vtciyo 89x: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 the7p t-fwrxu nj3+.gki-+)odsu 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 pz2f 0b6 zuwi5v) -rdjjressure 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 thelx*qs6 e k2k7o9w n+rq 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 gravity by tennis boj ; d9pow,:pballs thrown vertically upward ;w ,pod:9opbj 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 thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter (spher gvs 94apz1gy5ical) bubble of air from a depth of 14.05a zvps41gyg9 m in a lake. Assume 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 presb4cp 5bmuv tvps:s/n:iw3b7d 57avc 8sure in the air on the following two days: u74/bbc w:5 7:v3v5c 8pvinsdasbptm
(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 wzl-6 jh:3 cnwof iron at STP, and when it is a h:ww3-cl6 zjnsolid deep in the Earth where the temperature is 2000$^{\circ} $C and under 5000 atm of pressure. Assume the bulk modulus (90$\times 10^9N/m^2$) and the coefficient of volume expansion do not vary with temperature and are the same as at STP.    %  ----待选择----decreaseincrease 

(a) Use the ideal gas law to show that, for an ide15/ajgvn d +c3*zwcpy2e u. pa0bw /jlal gas at constant pressure, the coefficient of volume expansion wjj1 bp gluv +/2 a3d.z/w5 apycc0n*eis equal to $\beta$ = 1/T where T is the temperature in kelvins. Compare to Table 13–1 for gases at T = 293K (b) Show that the bulk modulus (Section 9–5) for an ideal gas held at constant temperature is B = P where P is the pressure.

  In humid climates, people constantly dehumidify their cellars to prevent rot andb)e7l99qgz 9nh 6a o suj+z8ei mildew. If the cellarzjhg+s8i)z n 9lo67 e9uea9qb in a house (kept at 20$^{\circ} $C) has 95 $m^2$ of floor space and a ceiling height of 2.8 m, what is the mass of water that must be removed from it to drop the humidity from 95% to a more reasonable 30%?    kg