Which has more atoms: 1 kg of iwks3t.h3rh 4sron or 1 kg of aluminum? See the periodic table or Appendix k.rhw s4s 3ht3B.

Name several properties of matu pc :s6nas )+*49bfdyxpg r1g 78at5yzjrc8oerials that could be exploited to make a thermometeras6 bzt5f: s8cggc 8x4o7uyp dayrp n* j1+9)r.

Which is larger, 1 C -j7 qgcqma ;x:djmgjeswe,0(h 3ee lao954y7 $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B is not in therv 8ixg y8,dqomx0c eh-pf5x 6(uop*: omal equilibrium with system C, what can you say about the temperatures of A, B, and c: (8ie x y 5fx*do6xmv8op0,p ghuo-qC?

A flat bimetallic strzvdi * ; ob 25t)ccwey;svtl/0ip consists of aluminum riveted to a strip of iron. When heated, the strip will ;)/v5 o se ;cytt lzdvic*02wbbend. Which metal 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 cobvi(0k-px p+bi6g 5tz efficient of linear expansion $\alpha$ are $(C?)^{-1}$ and there is no mention of a length unit such as meters. Would the expansion coefficient change if we used feet or millimeters instead of meters? Explain.

Figure 13–27 shows a diagr9rosofi: m5 g-b1 8 fyaq1d2dgam 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 cont-gs:idoomay1 rf9 gb52 d 8q1faining liquid mercury that conducts electricity when it can flow to touch both contact wires. Explain how this device controls the furnace and how it can be set at different temperatures.

Long steam pipes that are fixed at the ends often have a se(6*9 eu,7zbn)rj ichh cs1:u slgwq d2ction in the shape of a U. Why?1),2u s deqh:bgjr97h cun w(lsc6*iz

A flat, uniform cylinder of lead floats in mercury at 0 (y5qzv6)*yi rxrcr1qpp80,z ptbh d5 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass th-xx 2* tuu/qf/z : hk(-dzbwnjermometer is first placed in a hot tub of water, the mx-hkz: j bwu*ut/xdn-/ q(f2 zercury initially descends a bit and then rises. Explain.

A glass container matdq8 )dn941vq-sd-vxr 3hcb ty break if one part of it is heated or cooled more rapidly than adjacent parts. Explain.4vbxt 8hr-9t1)d qqvsdn3cd-

The principal virtue of Pyrex glass is that its coefficient o8ndo5g lqdio50j ak/( )zlym9f linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased 8(iyd09lam5z5l k dojn o/g)qheat resistance of Pyrex.

Will a grandfather cr9oo k0/tly 7plock, 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 cause its bottom and top tom, ;2hv-ncu. foaw -tp bulge so badly the can will not stanpa,;2tu m n-cw.o-fhv d up. What has happened?

When a gas is rapidly compressed (say, by pushing down a piston;-7qvp+a ve,3rixkeexqls1 1p4ndo)), its temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperature using the kinetic theory, in particular notinr3 vxpkl71evoq1q4 dpan-eie;x+,s) g what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force on an aluminum sphere submerged in water increnx zj6++ 2gdpols *qf:+rxn w 4.ecw4 cu4w,otase or decrease if the temperature is increased from 22t c4g6fn4 ,wjl+4* +z o+ dp.rwqwxs oux:nec0 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theory and the relatioytlg p 3k.4784w5ahayv sfbh sa56ug8n between average kinetic energy and the absolute temperature.h 8as358g6y bfv u wya4g4s7htlap k.5

Explain in words how Gay-Luss;/ en8z j -g(sixkmry,ac’s law follows from kinetic theory.

As you go higher in the Earth’s atmosponwh it39f 9n*f7oh tubzc b23mt47z 5here, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the mi z2+oakf7(eszn rwl15nimum 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 the Earth duez ( 7+onl2r1wfszak5e to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at room temperaturehem -we6d6p ))vvw7e y. What can you infer about the molecular properp)h 6veyedmww7e 6-v )ties of one relative to the other?

Explain why a hot humid day is far more uncomfort//zb.z br6u ul (g4 jszr*8mntable than a hot dry day at the same temperarrbuz s*(6ltgb/u /. 4z8zj mnture.

Is it possible to boil water af24guv hgwvj.u045bmm0wg,ni t qqb/7 8; pzst room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is thek yf3u4gcfaw;tb* ;/a same but the humidity is different. Which is more dense, the dry air or the humid aiu;gbayf*tc 34wk f/a;r at the same T? Explain.

Explain why it is dangerous to open the radiator cap of an overheated automobi lp1tulxoxw:we39o(- lel1 elw :x9u(pxtow3 o- engine.

Why does exhaled air appear as a little white cloud in thr ;qgdmu f8.x1e winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram copper penny?pf; byl2iuwt+al o2r 5,+pb)npci 35z   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare to the numbu3dz oo)xi:7c7- c 7mi*hae qcer in a silver ring of the samedcz -o ecm7ih)uo3iax * 77cq: mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this off gqg zi 63t,jz9.h)xn the Celsius scale?f)9thz. 3, x gf6zgjqi   $^{\circ} $ C
(b) The temperature of the filament in a lightbulb is about 1800 $^{\circ} $ C. What is this on the Fahrenheit scale?    $^{\circ} $ F

  Among the highest and lowest temperatures rkfxwv(2fs7wzx(,0 wv ecorded 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 alcoholcfk) it1 enb5ca6 y/8 2qnvu)v column has length 11.82 cm at 0.0u/ybva)q)inc8fe ctvnk2 651 $^{\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 sq*h6(u efgv((pec.n klabs 12 m long (20 $^{\circ} $ C). How wide should the expansion cracks between the slabs be (at 20 $^{\circ} $ C) to prevent buckling if the range of temperature is -30 $^{\circ} $ C to +50 $^{\circ} $ C?    m

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

  The Eiffel Tower (Fig. 13–29) is built of wrought i8spl *kk 2wwiz/4a+rc ron approximately 300 m tall. Estimate how muca c/kl wsw*ip+ zk84r2h its height changes between July (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 fit, rivets ta y4o crqn1e,k5z s04zhat 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 1.8711y5n4s 4o,qz 0aerkcz 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 40h11xakygy yca9,psj qx/8gat 4 $^{\circ} $ C is $ 1\times10^{3 }kg/m^3$ What is water’s density at 94 $^{\circ} $ C?    kg/$m^3$

  A quartz sphere is 8.75 cm in diameter. What will be its change in vlnn* d5f)6 77;ktns:pw wgmkvolume if it is heated m* 6v7):dnwk;nk g7l5fptnswfrom 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350.0 mL of water at 10 vuys;qpgcp 1h4 k,e5x)um3x7 0.0$^{\circ} $ C. If the temperature decreased to 20.0 $^{\circ} $ C, how much water could be added to the glass?    mL

  It is observed that 55.50 mL of water a15,entu c ota3t 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 :g a6 qyso4ali+quomq;1t 8,d 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 in a long, narrow vessel so it can expand in essente3yela sq)s7t /lnqn9yi4 20jially one direction only, show that the9lnys 4nle2 jqty0as73 q) /ie effective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change li05hkro us(a(j.pt,6xt 3qq 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 coefficn kz:xokyz9v1 6 q8v(oient of linear expansionok9qoy zxzn8v 6:( vk1 $\alpha$ 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 isotropicp1f. qsn ) 1:3:zs -ux0hat cga5jleye 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 cl9.2n yh; +sboontb4./ say qaqock is made of brass and keeps perfect time at 17 9ssyq a ;4+bbh2 oon..tq y/an$^{\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 0.140 m .-pbd6 wihr7sm. The bulb has.-r6b7i p wshd 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 wheel of radius 0.41 m is rotating j e4godf/ .u1habout its axlefjdgo e/4u. 1h 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 de tg)vq *n:yex7sired length when at 15°C. How much stress is required to keeng )t7yvq: *exp it at this length if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-sect9w+ww xjxt8fvv)1 k2rional 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 diameters b6 6iulmh5+o 3kmm,d 134.122 cm at 20$^{\circ} $ C is to be enclosed by an iron band. The circular band has an inside diameter of 134.110 cm at 20$^{\circ} $ C. It is 7.4 cm wide and 0.65 cm thick.
(a) To what temperature must the band be heated so that it will fit over the barrel? $\approx$   $^{\circ} $ C(Round to the nearest integer)
(b) What will be the tension in the band when it cools to 20$^{\circ} $ C?    N

  What are the following temperatures o/y c gwc*x-n:in the Kelvin scale:
(a) 86$^{\circ} $ C,    K
(b) 78$^{\circ} $F,    K
(c) -100$^{\circ} $C    K
(d) 5500°C,    K
(e) -459$^{\circ} $F    K

  Absolute zero is what temperature alfvr 3v;,f gfjq4/:p b( o2h)mrte2c on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interiovl6 u o.9yc lbb,srsp375hgjz;/tt2 rr 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 atmosphericbou,b3 u7pfn:rbzk :9 pressure and a temperature of :f7 3bzbubp rouk :,n9about 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 oxygengw f8y7+vyahdh 2h )nwa ;a2*s at STP using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of nitrogp n d:t47:osku vyoy2lbrj:/7en ($N_2$) 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 18.5 kg of nitrogen b(b y r vr.rj/*c5 f(mvxz)5jp($N_2$)
(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 aevbae/9mu 7 rg:80tbgas 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 container holding 105..r j l2tgp 3-c)xbcuy(0 kg of argon gas at 385 K?t l).3gu-pycx ( 2jbcr   $ \times10^{ 8}$Pa

  A tank contains 26.0 9shw amg1y 7r1kg 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 the air inside the ballokp w.-8 cdkxzv)hvl17d b* aj;on, which makes it less dense thava-k. pd8wb;kj 1)c7*xlvhdzn the air outside. Suppose the volume of a balloon is 1800 $m^3$ and the required lift is 2700 N (rough estimate of the weight of the equipment and passenger). Calculate the temperature of the air inside the balloon which will produce the required lift. Assume that the outside air temperature is 0 $^{\circ} $ C and that air is an ideal gas under these conditions. What factors limit the maximum altitude attainable by this method for a given load? (Neglect variables like wind.) $\approx$    $^{\circ} $ C(Round to the nearest integer)

  A tire is filled with air at 15(nw) ,.tfyk xb $^{\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 18.0 /llp-li6 p zkd1y j4.*8mhzxb $^{\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 20.0 k:nji94/n *hf .) ilfqykoo7f y j)-vy$^{\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 molecules / //m4lwljvr: sxq(itp- :k ko. $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.00j2j q v6ywv si+f9wl3gu)3z)j0 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) moles, jj ,*vm ou/c o /yl/mkn-*ji8f   $ \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 volumuuqf*c qqn9t94 q 8nm5e 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 inh m+x0iy4 cqjd*ale that were also in the last breath Galileo took. [Hint: Assume the atmosphere is aboudiq*+ 4cm jy0xt 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the aver+3wqtzbl:i od9: wou96mr1x jdzf1 2fage translational kinetic energy of an oxygen molecule at STP? wr2t9f: 1o+wil 61ufdj 3qxmzd9oz:b    $ \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 su stz(-ebtc rzb r0oi9 s6 9hdcr8;h2)qrface of the Sun at a temperature of about 6t r96(; c8b2zec)srsqdh ho09 tzbir-000 K.    m/s

  By what factor will the rms speed x:/kjok ltwlh s7*k;tl+5v 3gof gas molecules increase if the temperature is inc;l3l vsg l7 jw*x +t/ko5hk:tkreased 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 q907q*u 6;ejvglpqnspm8 1xdin units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8.s 10e j9pxvun q6mg7*d;qplq8 Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a q9w 3rx j9k*4kzmgv yhc(kf 9r -;nra6m:,vvs 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 fdi9:jw(bi: -:.2y miw at6f ame3pxoheld constant, by what f j we.ypii: mftm:-3x9aofd26:iwba (actor does $v_{rms}$ change?   

Show that the rms speed of mole 0fqkt3qd 2 px.w;sv*3u8bdtycules in a gas is given by $v_{rms}$ = $\sqrt{3P\\rho}$ where P is the pressure in the gas, and $\rho$ is the gas density.

Show that for a mixture of two gases at the same temperature, the ratio of tq32peicxa 38p heir rms spee q ca83pxi23peds is equal to the inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen molecules contained ijrlh+xo. j82 dn 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 oxygen molehe6tfr(0b*npi 5tg ,a cule 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 atwc-m 6f2 bwa2sl0,m o4hcw,du STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an aminwhw5ngs0 k );to acid whose molecular mass is 89 u in a living cell a )st5n;w 0hgkwt 37 $^{\circ} $ C.    m/s
(b) What would be the rms speed of a protein of molecular mass 50,000 u at 37 $^{\circ} $ C?    m/s

Show that the pressure P of a gas can be writ*3/zs e*yr6jxr9 xlx 7l* 6tr,ro vqiqten 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 urabgq.jsfjq 9)w8+ k/ kmnium, $^{235}$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 pressurk8 ,lswx34 deoe, in what phases can $CO_2$ exist? (b) For what range of pressures and temperatures can $CO_2$ be a liquid? Refer to Fig. 13–21.

Water is in which phase when the pressure is 0.01 atm and the temperature is (oei/ x)g-5p94hwo,;bn b xxpka) 90-pg) /o,xen945ob ;xkp b hxiw $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if j lpq)rvy: i6(,6 vvyqthe humidity is 50% on a day when the temperature:lv(p6 v),6y rqqyv ij is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressurhqpp )i1s eq:/is9 c9se at a place where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure a7e;l1e ,ffjhmt a particular place in the mountains is 0.72 atm, estimate the temperat j 17he;emfl,fure at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressm - pf9x1f*jpq.bt ,dw9f:doxure of water is 530 Pa and thfq9xd1p.,d: 9mo w xf*b-pfjte relative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of wsw plpnq2qxmp 6efj7e.tt/y::o * y6-ater on a day when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cooker if the wax) p(fw:ry xkaon,*f4ter is boiling at a temperature of koffy p(4:r*,) nwax x120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room)w*80o n;n5d t bhadua 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 n4p94 fxwvf9w5 $^{\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 gi;x2nq*dzt*s lycine molecule (see Table 13–4) to diffuse a dizdi;*2*s nq xtstance 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 interior through tiny tubes+ k/pqa c0rjtlgucn b s121n9; called tracheae. An averagnbqpg/c a21 9r ; sulckjt1+n0e trachea is about 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 mmtfqch4q, (b: qyw(l)easure has been calibrated at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A precise steel tape measure has been caf-mbo l )+c 7yg:ib(pz(o i;tnlibrated 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 norma*l5)3 ivwyr*l. , xfv y:eystjl room temperature. How much error will be m*s )ly3.vvy5wy , x*eirt: fljade in a recipe calling for 300 mL of cool water, if the water and the cup are hot, at 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in a helium gas cylinder is initially 28 atm. After qe(t6f)en, qs x/zk g7many balloons have been blown up, the ge/ )q(7x,s6tnzfge kqauge pressure has decreased to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air moleculeo7pk. 0+rzds8xq9):m3p)bth e g h4f eudh2les in a room of length 6.5 m, width 3.1 m, and height 2. q :ks3d2pl)e9zxeeo8f.0m 7hpg t +b udr4hh)5 m. Assume the temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the de6,frx2 n)sti /m u(/0,slkctyxu x )censity of matter is about one atom per $cm^3$ mainly hydrogen atoms, and the temperature is about 2.7 K. Calculate the rms speed of these hydrogen atoms, and the pressure (in atmospheres).$v_{rms}$ =    m/s    $ \times10^{-22 }$ atm

  The lowest pressure attainable using the best available vacuum techniques is abn,7nh,walx s-out,, xl7-nhnsa w $10^{-12} N/m^2$ 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 wkje7h2b ug5;8dyl.f(n ne+,smok;tj dp: g 5lungs to full capacity of 5.5 L when 10 m below the surface, 5g 2n+en;ue7tfmjko g5 wbhly (. d: djk,s;8pto what volume would his lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moon en)gqiwj1g; *av9 hhua/u/ px3rters Earth’s atmosphere at a speed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this speed) xgauhrvg 39ah*qip1/;j uw / correspond to what temperature? (Because of this high temperature, the nose of a space vehicle must be made of special materials; indeed, part of it does vaporize, and this is seen as a bright blaze upon reentry.)    K

  The temperature of an ideal g3sj 2hdfb 5 (3 9dc lfleos,8dhdn5il0as 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 volumev:y:pham *x6lnard - 4 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 pressur bfws*g2ph7 cmeb2 86oe at the surface of the Earth, estimate the total number of aiwpom 2e7fbs826c *bghr molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contained ifpfqo8 hu; ej-+npb-,h5gu6 bn 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 ik r,tlfv7- 6unj1gn9fg q 2b8bn a hospital has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at agbtv1 fk,- 8 r q2l6njbgu9n7ftmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of wj; ,dz *t9d+0kyfdziuy5 h(wliquid 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 gasolincymylrwm*;u vzm n;0t3+d*y, 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 the Earth’s equatordcf1*enwst:8nsjf h+a) 1h1 s 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 gl nc3nuju8q t ev)x02b;ass 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, adoptoyz4fxfz5pln +yo07 u hgw842ed in the 18$^{th}$ century, was a platinum bar with two very fine marks separated by what was defined to be exactly 1 m. If this standard bar was to be accurate to within $\pm1.0 \mu m$ how carefully would the trustees have needed to control the temperature? The coefficient of linear expansion for platinum is $ 9\times10^{ -6}C/^{-1}$. $\pm$ =    C$^{\circ} $

  A scuba tank, when fully charged, has a pressure of 195 atm .kom(jl1 * q4jux f,joat 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 i1d 4e7vjd-7 nyvef f4r.kx,v$ 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 bb*r.p h/ vt5krp m8i ji,s*9) -axyqo-ev-r uzalls thrown vertically u ,mv / *r rvye .-*-hpjsi)-kpq9z8raouxt 5ibpward 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 (s 88ns)e sz;kcepherical) bubble of air from a depth of 14.0 m in a lake. Assume the;cs ksn8e8ze ) temperature is constant at 298 K, and the air behaves as a perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure in the air on the following o n3n8ub cj-b*two days: o8-b ncjb*3nu
(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,fmy5 -2eb4ajr and when it is a solid deep - y25ma4ebrjfin 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 ideal gas at consta9u38mx4kugxju4vew go+ e1n /nt pressure, the coefficient of volume expansion is 9gwgnu4v8u4jx3mu+eke o / 1xequal 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 the1e ej fi5pbs3v6m4t8f ir cellars to prevent rot and mildew. If the cellar in a hous1jtseiv8 65m3f e4 bfpe (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