Which has more atoms: 1 kg of iron or 1 kg of abguo(m8s ds(rew+bm 4 9 9-kbwluminum? See the periodic table ow4 +(9 r( d-km8bs buom9gswber Appendix B.

Name several properties of materials that could be exploited to -q-pc pao2*cn make a thermometer-- nq*pcoca2 p.

Which is larger, 1 C lydvf (mwg -;mz0a((p$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B is not in therm,t2k 0+ q adgp4albesj c2,iy8al equi+j bdsl kciaq,,p0e2 tyg82 4alibrium with system C, what can you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to a strip kvylzo2 / 0cka l*0(etde pqg7z,)z .pof iron. When heated, the strip will bend. Which metal will be on vzdz/z0c.e 0ka2g)o pl*y7ql(t e,kp 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 li d8mhaxz0/xnf 5u)9utnear 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 seh8 i t- jp;auy.3gk* dyrxr 2. y6qd+n5/adnused 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 vessely6nk.yh +g. e 8i3dq djrxyr*5udap -2tn;/a s 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 have alou2r vg 3m3.j ib/e-g section in the shape of ar3vg -oblegi .jm/ 2u3 U. Why?

A flat, uniform cylinder of lead floats in mercury at.)y4kedj0ao)t3fj ow 6 nars* 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometer is first placed in a hot tub of w edsy+: d7mh1cater, the mercury initially descends a bit and then rises.:dd 7me+yc1sh Explain.

A glass container may break if one part of it is heated t+++antxpmw 1or cooled more rapidly than adjacent parts. Exp+p 1 axtn+t+mwlain.

The principal virtue of Pyrex glass is that its coefficient of linem8b(upufmhs)1 j/ 0 0st3k i7wbt) 3iixbcu+rar expansion is mucpb w/01uhsi+jksbtm3brum 8ic) x0if(3 )u t7h smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather cl*haj*xxzd n39ock, 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 to bulge so badly the can eelp,jk-w 1+i2xj1 xk+ 1gqd k6o8jlw will not stand up. What h wje8 j plq k6+xxij,dk1lkgw211o-+eas happened?

When a gas is rapidly compressed (say, by pushing down a piston), its tem2,9x 8ydewn*+dcz m;ajl ae r1 2kmg4tperature increases. When a g rt29* ed1 d4m;k, 82anzjx egyl+awcmas 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 when they strike the moving piston.

Will the buoyant force on an aluminum sphere submerged in water inqoxd 9(gr15p +.g0uhe8ckb a62b qmmacrease or decrease if the temperature is increase x+g9pe bm (8aq6go.5m dk2hc0qab1r ud from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theory+r jpjiy,edbh57, crhpz8n 14 l/me.w and the relation between average kinlyzmrc8h, i,b4.p5 p hj d+e1e/n7 rwjetic energy and the absolute temperature.

Explain in words how Gay-Lusswxbu 6 -jy)q*sac’s law follows from kinetic theory.

As you go higher in the Earth’s atmosphere, the ratio of0; y vxabm9+ jdyyys02 $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to theo*x :gu4 +umno minimum speed an object must have to leave the Earth and + n: gmo4ux*ounever return. The escape velocity for the Moon is about one-fifth what it is for the Earth due to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly tha(-su; d)lz22tahge 0yryom9 zn water at room temperature. What can you infer about the moleg(szu0l2e tamr 9h -;yzdy2o) cular properties of one relative to the other?

Explain why a hot humid dam -x8bn9 uzjyc1 xio4m3qu8k. y is far more uncomfortable than a hot dry day at the same temperaquxi.x -8m8zk3m c9nyobju41 ture.

Is it possible to boil water at room tempf3hue6uc*ru14ix*bllq - i6a r +rq:l erature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the humidity 2xmefem4)5 qvis different. Which is qefxm e)4m2v5 more dense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap of an overhe,tg4dcni hs *z)u*vh7ated automobile ennsu7t,*z4*h)d hi vgcgine.

Why does exhaled air appear as a little white cloud in the winter vy,vbhc98p*n (Fig. 13–28)?

  How many atoms are there in a 3.x ui:sh)dd v.. t:y esrk19bf,4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in asd; b7v0)seqcp8 wca1 26.5-gram gold ring compare to the number in a silver ring of the same mass;87s e0cdvw cbq) s1ap?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this uw1ni-p-x+og4w j/3 w5cjpq d on the Celsius scale? 43n- qx 1cj+iduo-w/g5w ppjw   $^{\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 recom v5v wcl3 c;(ys-tc2-m dxo6jrded 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 thermo3wb)v v*3hq6 bakd9 ,1kslycmmeter, the alcohol column has length 11.82 cm at 0.0 3cva)w*lk dby,19 ks6qm bvh 3$^{\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 sm0f)lb:.dk gn mkjx .+labs 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 iron approximaujk5m-p.cw+3r n-dgutely 300 m tall. Estimate how much its height changes between July (average temperature of 25°C) and p .-urkd w 35-j+umgcnJanuary (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, ria6r 7hh6amrl.zj:8o q lc*a /fvets that are larger than the rivet hole are often used and the rivet is cooled (usually in dry ice) before it is placed in the hole. A steel rivet 1.871 cm amh8 .7:6jzc qaa*6fr/ lorhl 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 at3 l +xrv1equy9 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 kz jt8y+z/k + 0rl*ixtvolume if it is heated z0ltyxk/ *+jzkitr+ 8from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is fi py2 ur+(tk0iwlled to the brim with 350.0 mL of water at 100.0$^{\circ} $ C. If the temperature decreased to 20.0 $^{\circ} $ C, how much water could be added to the glass?    mL

  It is observed that 55.50 mL of water a ubxz2g7+p 7xtyd* )rkt 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. ckjxu0myh ext 4z -4w20pl1(w 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 ingixjz4 6c3m *i essentially one direction only, show thati63 4*mzxjicg the effective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the density svsc+ 8uxu7iu.t t7mu0 ,z:oq$\rho$ 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 wid5 bylrcy+n+hhkdgv.91-u(*v m)u ey ;) rwg vuth w has coefficient of linear expansi+)rh *evb;n uu5rwc (yl1)kvvg+mh y.-9ydgu on $\alpha$ 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 solid,jq hkf xfy19,cji0fx 7453yatpg4b e6 $\beta$ = 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 grand8nvh:g59f y * / kc oawvfok+(bugx1m:father clock is made of brass and keeps perfect time at 17hf mx*ogkuk+gwv 5f/ :c:nb (y19vo8a $^{\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 :(8vqk2bb-cpl/zon:s h eq9y inside diameter of 0.140 mm. The bulb has a volume of 2b 8 qzo yhkb(/sv:cl- e:qnp90.255 $cm^3$ 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 jbi; tjc,wy+:.41 m is rotating about its axle on frictionless bearings with angular velociti:cb;+yj,j wty $\omega$ = 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. H+ qc,z dzq;al7sdkh4:h08 m wsow much stress is required to keep it at this length if the temperature increase ds:d4+ kzahzcl 80h mw;sq7q,s to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cro1/pey-8uys b4 naf*iass-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 134ho /qek )hxc+8.122 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 temperatun gsra+ f+7(tdres 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 te v;* fwupr( x1p1wlc-tmperature on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Ealbne( u9rosq*(7 fu zjn)vi,/ rth 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 q6 .uzov(mpn+; ae7aeat atmospheric pressure and a temperature of abn 7a(+mo.6v; euqpazeout 20$^{\circ} $C is compressed in the cylinder by a piston to $\frac{1}{9}$ of its original volume (compression ratio = 9.0). Estimate the temperature of the compressed air, assuming the pressure reaches 40 atm.    $^{\circ} $ C

  Calculate the density of oxygen at STP using the ideal gaswm s239mmvun) law.    kg/$m^3$

  A storage tank contains 21.6 kg of nitrogen twd8x9.sqc7 v ($N_2$) 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 nitaur7k 02 e x*8/;ojsudct5nnqrogen ($N_2$)
(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 gasqn wmdh. uj1:5 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 105.0 i1m+ gm a-oid-ls/ 7mnkg of argon gas at 3ldo- n+iimasm/7- mg 185 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg of ,,yc8 d g :q liafntx3):jg+ot$O_2$ 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 laar 0d.ib,( wjift by heating the air inside the balloon, which makes it less dense than ad(rji.0ba w, 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 airi v8rf)8 qidi- 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 t u gawmh-94wh)asq) 8cd : hckhc9;w)z bq,v-at 18.0 $^{\circ} $ C and an absolute pressure of 2.45 atm are compressed to 48.8 L and at the same time the temperature is raised to 50.0°C, what will the new pressure be?    atm

  A helium-filled balloon escapg5ajqc-b; 8hwlqni yd( wl/9qr+8p:pes a child’s hand at sea level and 20.0 $^{\circ} $ C. When it reaches an altitude of 3000 m, where the temperature is 5.0 $^{\circ} $ C and the pressure is only 0.70 atm, how will its volume compare to that at sea level?    times the original volume

  Calculate the number of molecul5d+yb+ r, d6ek,l (cqty ih2iwes / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in ) 9t eg75vtb6ohux2igkh29pcm u q.. o1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) molehso m9ykp rp18gom 9o 01s9ojvmw- i06s,    $ \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 5o44w lx mr(w,(5a63odtx *jtfv v *epj.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 ib d.4bm 8pelk8ly,(fzn each 2.0-L breath you inhale that were also in the last breath Galileo too zply,8lb4dm8(. bkf ek. [Hint: Assume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic 0q7df10*xshev fg:orov8 +i venergy of an oxygen molecule at STP? o *fo d v+sr:vi0fxq h7egv810   $ \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 thx+2 czgftalha ua e,q)6*m*- re Sun at a temperatueu2*a 6 ,hrm-tfgacax)l+qz *re of about 6000 K.    m/s

  By what factor will the rms speed of gas molecules increase if the temperature i-ya h/fq6*cvo s increased frovfcqy-*6ho a/m 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 5-ok h 1ywid kb3ty9;okm/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, yk19okb -h5td3;owyiand 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules iyz1)c (ffl;nd n 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 doubl ndv)pe vcuyv060 gf6uix6.0sed while its volume is held constant, by what fap0v)06ge .c yuvd6 ufi06x vnsctor does $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is g6y2 n4vy ku:hkgh,czsoi 56x-iven 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 temperaturop3 yw+pk0-zve, the ratio of their rms syp0-pkw v+ o3zpeeds is equal to the inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen mole (calk8qhgo5m3p3ur5cules 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 oxygen moleculs2iv;hb-h w,-u vgj39/ldad ; k nciv(e 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 xms2b+dtu4 je ,do1(dnitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of ai8 4fz2ta:w d- icnb0on amino acid whose molecular mass is 89 u in a living ceb-tno 84az0dw i: ifc2ll 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 pressur teg,gg/ig)821jc hhxv0 x4nue P 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 uranium,h 0;avj;xilkxy7f3f2 $^{235}$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 pressun m3ky*skw3 qe .ora7t bl+-*wre, 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 the6s bpsi//c aafg);; ys:xlw9x pressure is 0.01 atm and the temperature is (a)s ls xs fpay;:xic9/b/)w6a;g 90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the hyo g8 abha-co-n-x9w0umidity is 50% on a day when the temperature i-cn89- g -y o0hboawaxs 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a pl6 (wkcnmx 0lm9ace where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a parrjx d 9c lq560ck3ff,wticular place in the mountains is 0.72 atm, estimate5,frqc 3w kl9jfcdx 06 the temperature at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a days sz4s )b:h6kf 5ie -k30ggitb when the partial pressure of water is 530 Pa and the relative humidity iz s3it6 )bik -:beghk 0ss5f4gs 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressucz.egn vw-,(jre 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 pres j*jf v0b6qzq50h(vlg sure cooker if the water is boiling at a temperature of 1*z vvj6hg qf05 bql(0j20 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room of volumev vbt (0scv,c v7g7v)w 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 5 b3e9w/ t:4: kypmocxi$^{\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 diffus3i::w 1pbnred:9io oge a distanc913:b:now giopie dr: e 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 interhi:h o7r f7um38(b9xeyd0,0 hlyyr+gu iuh x. ior through tiny tubes called tracheae. An average trachea is about 2 mm long and has cross-sectional 7gb,ul03uyirdf +u.7ohexr 0 h 9:i (xyhh8ym 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 bt,f-c dj dk *o8xl/-cseen 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 measu )gt1;obnr+gyyu6ft 8h o+d 0bre 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 Pyrex measuring cup was calibrated at normal room temperature. How much error n5p y vb2tyz30will be mad5 zv bypt0n3y2e 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 helib)b0q 0dmv +zsum gas cylinder is initially 28 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 cylin)s 0bqd+0 vzmbder?   

  Estimate the number of air molecules in a room of length 6.5 b8bt:2w bn9obxjk9: ym, width 3.1 m, and height 2.5 m. Assume th kbjbo b982wxtnb:9:ye temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of mat zwdm.u7-6h4 jrkqp:n ter 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 u)aex g ld0/4jthe best available vacuum techniques is abouta40)/duje xgl $10^{-12} N/m^2$ 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 when 10 m below th/5zbnm -evg: nt-x++ay5xb o je surface, to what volume would hisxnvg oe+/b5 yjb +z tam-x5-n: lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moon entert6u xbaasd );-oho*zu.z3 nqq r2:d;ds Earth’s atmosphere at a speed of about 40,000 km/h Molecules (assume nitrogen) strikingb:2q;*6dd uon3)h. od-taurxq a;szz 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 reentry.)    K

  The temperature of an ideal gas is increased umjpz 7 w+vk e t84y*e(j),qchfrom 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 volume02 hhya6q un0g 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 surface of the Earth, esro/u:myi i2,w xz5lux rg-::nqpy8 9 9aog1 nptimate the totaliw8 qnz:o 29 -rgp /p:x9ygr:ulyxumoa,in51 number of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen a 0zw/uo-6:t d3dziuhmolecules 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 hospi6q )3 squth;tptal has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K ; qh tup36)tsq How long will the cylinder last if the flow rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of li (*jlf )5kqa3 w7blmdwquid 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 gasolineu08n;8 xqfq j+y;qgo) u, xfk9ne*gqt 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 equator at 2cqw9ti)ye33y(pq 6 ab)+ ckje5$^{\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 glys.,2i zu urkbxx-pq*y/ x)1jass 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 1;qrzzm(+kap pyy0*lin 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 ab-kxyo7 wn9 4xg /xgxa5u7a e1tm at 20$^{\circ} $C. The volume of the tank is 11.3 L.
(a) What would the volume of the air be at 1.00 atm and at the same temperature?    L
(b) Before entering the water, a person consumes 2.0 L of air in each breath, and breathes 12 times a minute. At this rate, how long would the tank last?    min
(c) At a depth of 20.0 m of sea water and temperature of 10$^{\circ} $C, how long would the same tank last assuming the breathing rate does not change?    min

  The escape speed from the Earth i7dh:ch29sf4u o on :trs $ 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 ten a wrnh-4vv,(epy5 j.j,g( dqcnis balls thrown vertically upward at it. How many tennis balls per second must rebound from the lid elastically, assuming they have a mass of 0.060 kjn e,pa(.y5v, gjh( q4rcv -dwg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-dkoj/.n8/f3 6 ccbzff g fii10riameter (spherical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant at b8o0fzi6/gf. c fjk/fc 1nri3298 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 thecx thjos xly3.ef:;-. air on the following two days: f.e 3o.xjhxls- ct; :y
(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 differen.2f8 se osfzs,ce in the density of iron at STP, and when it is a solid deep in the Earth where the temperatof, ssz8 fes2.ure 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 constant / xmeih*y6c1z pressure, thx*y6cme z1i/he coefficient of volume expansion is equal to $\beta$ = 1/T where T is the temperature in kelvins. Compare to Table 13–1 for gases at T = 293K (b) Show that the bulk modulus (Section 9–5) for an ideal gas held at constant temperature is B = P where P is the pressure.

  In humid climates, people constantly dehumidify tsdr ;yryj+l- s8dirfv(k7,ut*i i* j4heir cellars to prevent rot and mildew. If the cellar in a hous*vj+ sl ty*dsi7;fr-d krujy,4ir8i( e (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