Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodic tac5.pkfa2 52(vnp sx, +zi gukbble oc vzk nf k,2(b5g.+52 ppaxuisr Appendix B.

Name several properties of materials that could be exploited to make a thermos+8hxtsxh-p cu9g)btbd9hg*n2)h s6 meter.tg*h+hs n - s 926pbdutxbh)s)9x8 gch

Which is larger, 1 C pm ;4y glxrk afgr12/ t78ptz.$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, bun 6suw/p*q:bbx13 9pj9ko,ittzw r/qt B is not in thermal equilibrium with system C, what can you say abouw r zbtq/kupq3 1j*w9i sbop/6n,tx: 9t the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to a strip of iron.t87fp, ynt z2s When heated, the strip will bend. Which ,f8znp2 stt7 ymetal 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 of linear expansionk/qz3p1uwkf6zfqwb manl 671 / o265.h oifcu $\alpha$ 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 k -s85 1h5x.+koikosopu7vgoto control a furnace (or other heating or cooling system). The bimetallic strip cig hu1v5 k+sk7xo.o8-poos k5onsists 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 different temperatures.

Long steam pipes that are fixed at the ends often havh7ts5gudtrw13f / ck *mgt1ade,.i*e bbf+.be a section in the shape of a U. Whbgt,ui5..+b1e d/1bk3 adwe* tctf*f rs gm7hy?

A flat, uniform cylinder of lead floatsnih)-3rvybpi3z 3o n8 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 pla ku(c0d k4yua1ced in a hot tub of water, the mercury initially descends a bit and then rises. Explain. 0ckday k(4uu1

A glass container may break if one part of it is heated or un:0tg8bn618f s .znbneq xj) cooled more rapidly than adjacent parts. Explf :8n8znx0ubbnen .g1)sj q6tain.

The principal virtue ofusc1/,cuf 9 ai Pyrex glass is that its coefficient of linear expansion is much smasf9u/c c 1u,ailler than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurathj 8m*ok6cak, e 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 to bulge so badly the cl mj47 x1jyoyyd l(9j-;6r gcoan will not stand up. What has happened1;g jdo yjy9jr c 6y(mxl4-o7l?

When a gas is rapidly compressed (say, by pushing down a piston), iq0dxl b4*pwrn8m04 qr pux i/)ts temperature increases. When a gas expands against a pistd qu*/in4r4 r)8x ppx0 q0wbmlon, it cools. Explain these changes in temperature using the kinetic theory, in particular noting what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force on an aluminum sphere submerged in water i (a;bsj28ik se* mhl,tncrease or decrease if the tempera8;*h(alijm s t e,k2bsture is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinet.gx) c(nx+an vb5((ka u k /g/u+tltyyic theory and the relation betwe +ga +t y(ukgx ck(t.(l/yu)nnx/5b aven average kinetic energy and the absolute temperature.

Explain in words how Gay-Lussac’s law follows fromnyr:i2 ( r*yht-cnup) kinetic theory.

As you go higher in the Earth’s atmoi+d wv8gofi 82sphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimuk jmi+nhm+ey( 4d 76qgm speed an object must have to leave the Earth and never return. The dn+jye+miqk4 ( mgh76escape 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 thano-1xdaz gy.smx q.7 e: /-wqyy water at room temperature. What can you inferw7-. dzmsx1.-oy/q egqy a y:x about the molecular properties of one relative to the other?

Explain why a hot humid day is far more unadh :v*)*qq ,t1 mjnxd5j jkut y28)lbcomfortable than a hot dry day at the same temperdjytl) :5tjkv m8 j,qd1ua)xnh** 2 bqature.

Is it possible to boil water at room temperature (20u- 5lwf5- +ub3h8tn/ rgbf-(nypsr lk $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the humidity is diffe- oqw:an*: )jyzh)lyerent. Which is more dense, the dry air oeh ):yq:o-jyanl w) *zr the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap ojh* 6+kvim6z 1jbe*pqf an overheated automobile+hvpkqj ej mz*16bi *6 engine.

Why does exhaled air appeardi:nt9x0 w1jfz1b vn + as a little white cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram coppe 8 5xhm7 jvz2qzb n7o4du,24fh( ne+2getcdsq r penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a v+1d2r 7lrkc duj4-sc 26.5-gram gold ring compare to the number in a silver ring of the samv-cjd7 d2c4ku +1lrrse mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this onaflhyh+t3 o + ey)-iu4 the Celsius scale?t4aiyhey +h +f)-ulo3    $^{\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 l7zpjkt e/1m 7yqzcfgzw2 ()vmfg -/n6owest 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 ca i jgr6z)1lj:olumn has length 11.82 cm at 0.lgj 1a6i: )jrz0 $^{\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 bx .7x9c bur2rzv td1w7uilt 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. le ,c 4 g91izg +sg,jbjb+0 :ebpcblpi m9..jk13–29) is built of wrought iron approximately 300 m tall. Estimate how much its height changes between July (average temperature of 25°C) and January (average temperat,e.9:jz j,g9 +s+4j0ipb.cek mbipll gbb 1gcure 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, ri5w3v tq*eh ehj/8 )6hh n9fozdvets that are larger than the rivet hole are often used and the rivet is cooled (usually in dry ice) before it is hodn z85t/h*9)3 fqvjhewh6 eplaced 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 ath-fmkt qbj8 6* 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 cz*a7m0xqy )ham in diameter. What will be its change in volume if it is heated 7x0)yzqam* ah from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to thb-yfnyw.h sa n54yb w7 sp5s)7 co)x9ve 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 5qlpgp q:w6u9 05.50 mL of 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 of iron. Ablajk/e06pi ( hfuo *0t 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 llks a bh,n-cyai74/ p 22bwi sv+/9giqong, narrow vessel so it can expand in essentially one direction only, show that the effective coefficient of linear expansion is approximately equal to the coefficii42c h/klai/sq27 vb-ans, gyp wb9+ient of volume expansion $\beta$.

(a) Show that the change in the densitv cc+6nx4cf b;sp;,nwy $\rho$ 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 lengoel l-(g98.)r7sxmd w npw- pyth l and width w has coefficient of linear exgyw89elp- o-.rx lp(7wnm d )spansion $\alpha$ Show that, if we neglect very small quantities, the change in area of the plate due to a temperature change $\Delta$T is $\Delta$A = 2$\alpha l w$$\Delta$T See Fig. 13–30.

Show that for an isotropic sol(gle *szi9p6s.ofr n3id, $\beta$ = 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 gram(,ab, q6f+mjqdy q(lndfather clock is made of brass and keeps perfect time at 17 fa(ym+l,md6 q( ,bqj q$^{\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 ofb ip9 p1t)pqa/ 0.140 mm. The bulb has a volume of 0.255 )a /bpqtpp1i9 $cm^3$ 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 cy7);sb8dd jxkh lindrical wheel of radius 0.41 m is rotating about its axle on frictionless bearings with angular velocitysh d)kd;7bjx8 $\omega$ = 32.8 rad/s If its temperature is now raised from 20.0 $^{\circ} $ C to 75.0 $^{\circ} $ C, what is the fractional change in $\omega$?   

  An aluminum bar has the desired length when at 15°C. How much stress is requircygygds:ld jn8so)p 1q1. 1 ;ged to keep it at this length if tsoy p.:cqj y 1gn gslg1);81ddhe temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of mr+xgf q3-) fqcross-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 134.122yx 6bq+/7sr gv 9jaui*lm6ul9 s: y3ui 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 temp2/yv- jzasah clq;qk*7 agq**eratures on 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 temperatuy6kq0hl/ l2vtre on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth 6ylwwieb:;. wand 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 combu- ajf99avyfy; ke (+jxstion engine, air at atmospheric pressure and a temperature of about 20(v;ajf-a k9+ yx yef9j$^{\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 ideal 6)umyy4pjbem; dj(olsbup 6sq *.+2lgas law.    kg/$m^3$

  A storage tank contains 21.6 kgc).xwg2kyltu n6i.8l 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 contaioh z 3)kooy-2oxw1vj5 ns 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 iswbr2t;k+e;0xuem2tbc/ kn o+h ;(d lv 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 105.0 kg g9h(pyp v*)w5v;prsw of argon gas at 385 K5 )9p;w hrwspvg yp(v*?   $ \times10^{ 8}$Pa

  A tank contains 26.0zv * i vkq .q1srlq)*5l,e7jxi kg 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 bl55ox npenpba,1 b8dz e5bbo,4+ul 8calloon, which makes it less dense than the air outside. Suppo,41 op85np,ad+l 5eobl bnbb5eu8zx cse 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 s4 o ;5dun-ye+i7yy f5kxdp,i$^{\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 +mupy-d m.- 0j1lvzj7+jhc ckbc8 qc/.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 anunpf p o(kb3 q lkeh(o.bbr:m:6w u47.d 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 moj1w r;w;z ixw1+l f2xf*0okpd1goe:d lecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How t0lnrkft;x ap52gq )d *-hty;v8kq+jmany molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) mole3nifvl(gye 4f6 rv 4f,s,    $ \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 57te9erak.4x 2*utcu w.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 breathuojvw60 ln/l *jmh5o5 you inhale that were also in the last breath Galileo to l0/hov6w55o ujmnjl*ok. [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 o kw2oae:q60 z gk,teg7xygen molecule at STPe kge2q,6o 07w: atgzk?    $ \times10^{-21 }$ J
(b) What is the total translational kinetic energy of 2.0 mol of $O_2$ molecules at 20 $^{\circ} $ C?   $ \times10^{3 }$ J

  Calculate the rms speed of helium atoms near the surface of the Sun a *8vhnncxg zsc7/58 z sl05d,) gay )etrtso,ut a temperatczeg/5noa sz7,5t8cnd v)ru)t0s ,8*y x gsh lure of about 6000 K.    m/s

  By what factor will the rms speed of gas molec4-tq;uka5 c dzules increase if the temperature is q;zc k4-dau5tincreased from 0 $^{\circ} $ C to 100 $^{\circ} $ C?   

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

  Twelve molecules have the following speeds, given in units of km/s: 6, 2,mf o7et5 7m)ce 4, 6, 0, 4tem 775 f)emco, 1, 8, 5, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of moleculesr3bvthlp93oy- m fp 2yc(3( xx 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 5b6are a( yqbj: pej*srxjxa02g;:l7 doubled while its volume is held constant, by what factor sb2x7(:* a rl;x6e a05jbp:argjeqjydoes $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is given bl jd onujcyebpi -;ua)s0o /4;:u.ig, y $v_{rms}$ = $\sqrt{3P\\rho}$ 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 thei: z f8.ehd4;bqpjb -h rppv5t7r rms speeds is equal to the inverse ratio of the square r v;bqp-p5f4r :bh pej7dz8ht.oots of their molecular masses.

  What is the rms speed of nitrogen molecules cont.o tvltt7.5v p)tz,h eained 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 o1adzp+mdbq 4y med(/h x:,kz2xygen 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 STP;yliwb.q a. e,l6m jh;zi4fs.?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose mo7b6qj0ukz0* xb:hs h mlecular mass is 89 u in a living cell at 3b 7mz0bh x:q0u6*jshk7 $^{\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 writteh,gh v*nr/zr35b+qvgl4d :g2i k ye8rn 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 uraniudifr-a2kd)49b 4or z fzqq 18z4gfnm,m, $^{235}$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 whjc tfgoj.n c+ *jrg(4.at 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 / wtpwd *8:c0k ntqikyve(0i qxq1a.7 atm and the temperature is (a) p(t:x/necw1vwid y7 k8i0qk0 at.*qq 90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately j6jtmca p7+7n)dle(jne -7n a) if the humidity is 50% on a day when the tea 76+n na- 7c7p)mntljd e(jjemperature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where watery((4 rqz-6ac6 stb qgz boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a pazzzbn1:h5*tdn x 5p:e rticular place in the mountains is 0.72 atm, estimate the temperature at which wan *:5nb p5zzh:zdex t1ter boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of watw guv 7m3lzh+,mv7l9 wer is 530 Pa and the relative huv9 m +l7 ,lvhww7zmu3gmidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a *c3 ,:le4xz 4zqkn hecday when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressurq kf7tk;f9*)7am( f+ qdzdoeil2w6db e cooker if the water is boiling +ik 67d;ltoef*b)9qd7 kmqadwf 2z(fat a 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 room of vol3mp6;fnt2v) ogrb( ,cix *wo2(tttb tume 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 d3y ib5r f+)0umtt pz+qg0tr7ee ud;p.ew point of 5 $^{\circ} $ C is drawn into a building where it is heated to 25. What will be the relative humidity at this temperature? Assume constant pressure of 1.0 atm. Take into account the expansion of the air.    %

  Estimate the time needed for a glycine mx4u27d-r nylwcpo b.1fi*c6h olecule (see Table 13–4) to diffuse a discw.i 72 nrxf cdp6lyo14hu-b *tance 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 thrxkgblv,fb865tz(ivey9,)ep1 glqviq j3 4 d6ough tiny tubes caz, v93 vqp5)b ldb1 gf4 eliyj 66kveit8g,xq(lled tracheae. An average 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 m obz:e*is owmq-rlhwzd)n 165: 4a( kgeasure 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 +w,yhb 78j /vdmosww6,buex/4k7 tuhhas 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 temperaturm6ma rb4*ere b:v ua kf*po;vg;2+f, le. How much error will be made in a recipe calling for 300 mL of cool water, if the watef:6ae2 l*obm+rmv egpv,arb 4f;u*;kr 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 1 e-pb)fcw ,:3kkdgovmany balloons have been blown up, the gauge pressure haso: ,)fdk-1b wpgve kc3 decreased to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air molecules in a room of length 6.5 m*iy7/sjhe .hvj*z z -h+ tn49rfakjx 3, width 3.1 m, and height 2.5 m. Assume the tempez ei*h-+zr tj.jj7n39 fya xhh/4k *vsrature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of m qg,+yk )d/busatter 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 a)1w ohy z4o9x66yo qtvttainable using the best available vacuum techniques is aboqo )6wooyx vy169z4thut $10^{-12} N/m^2$ At such a pressure, how many molecules are there per $cm^3$ at 0$^{\circ} $C?    $\frac{molecules}{cm^3}$

  If a scuba diver fills his lungs to full capacity of 5.5 L whev4i2j wceb92 vn 10 m below the surface, to what volume would his lungs expand if he quickly rose to the surfa jb2i9vc 2ew4vce? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmosphere at awz d7+)g :nb0j5- kyv /muph1c3gpjnf speed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this speed correspond to what tem3 fhnp wvk)my+17-zb g05d jgunj/:cpperature? (Because of this high temperature, the nose of a space vehicle must be made of special materials; indeed, part of it does vaporize, and this is seen as a bright blaze upon reentry.)    K

  The temperature of an ideal gas is increase p8j.qssw( 73x af,cxod from 110$^{\circ} $C to 360$^{\circ} $C while the volume and the number of moles stay constant. By what factor does the pressure change? By what factor does $v_{rms}$ change?$\frac{P_2}{P_1}$ =    $\frac{(v_{rms})_2}{(v_{rms})_1}$ =   

  A house has a volume of 770x.v h 1xit 0c h4h*kbod9+fv4mm$^2$ (a) What is the total mass of air inside the house at 20$^{\circ} $C?    kg
(b) If the temperature drops to -10$^{\circ} $C what mass of air enters or leaves the house?    kg

  From the known value of atmospheric pressure at the surface of the Eartha 6 (s3xk,cs. 7upxqyxsy0 i+o, estimate the total number of air molecules in the Earth’s atmosphexa 7so6s(yyus0.cpxqix3 k+,re.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen mole; 2l-dsb8;+fd6 z2d qz wzhxwmcules contained in a 7.6$-m^3$ volume at 4.2 atm if the total amount of nitrogen is 1800 mol?    m/s

  A standard cylinder of oxygen used in a hospital has gauge pressure = 2000 psi (f9hp / sye1xu,13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure, is constu e/xh,p9yfs1 ant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of lisqaii 2/2u +bg tml-+gquid 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 gasoli2 quzbh-mu 4t-nf 4uw2ne 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 Eawsi4p. w1dd 1urth’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 glas5 w50qxq f4ayys 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 in9/mor h2q5jpd 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 s p0)t+ iq6by r3zlfcw j49g+qatm 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 tmc 5p,g)ebh5r/x zk0v he 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 balls throh(pnli .5iq,mqw73 pn wn vertically upward at it. How many tennis balls per second mustn (,h35i7 nmwplq q.pi 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 (sphericaiht0aw 1 5f;(vaquth+g 10bhtl) bubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the air behaves as a perfect gas. How large is 5 tu0+i1hbqw fvt0g1 a( tah;hthe bubble when it reaches the surface?    cm

  Calculate the total water vapor pe 6hmno25x .rjky0) orressure in the air on the following two days: 5h.m2o)k6 x0yrenjro
(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 b3x*.k/f7v *t ot wz(1uk*rtc sh.awe when it is a solid deep in the Earth where the temperatuw t x1ua.*c*v(b3oz/hkwf.r est*7 tkre 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 wq2/zn t*b )ta-pp( gfconstant pressure, the coefficient of volume expansion is -bpngpt*2wa qt( z)f/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 1(*yytg2oqax to prevent rot and mildew. oa *tyx y2q1(gIf the cellar 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