Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the perijax6 p3;vls 5 pswe8g*8jpv(2 c/dcexodic table or Appendix gjexc6c 3pd5 s(8 aj2svep* /xvp;8wlB.

Name several properties of materials that couldwl)1mxv94 g ec)snzffkm;ev 3)or; f- be exploited to make a thermometz)cmem 9k1fg-x3es nw rf);vo;f)4 lver.

Which is larger, 1 C ,9mzva8 zz: mxqc a i856wp;-)z -dupsu;hfei$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium witcusmf 68*4p3p- :fxxv 4xpeps h system B, but B is not in thermal equilibuf6 v*xx4p3e8f-p4s c:psm xprium with system C, what can you say about the temperatures of A, B, and C?

A flat bimetallic strip consisaa9i3qgk zzga6 1iai 3p0.y9lts of aluminum riveted to a strip of iron. When heated, the strip will bend. Which metal will be on the outside of the cur3zgi pq ka6a g9i9i.ay30 1alzve? [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 welk5z 0fweb 6a u (ji4ee:91cnor;7xlinear 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 sif*adi 3cmb:r -mple thermostat used to control a furnace (or other heating omca*3 f rb-di:r cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch is a glass vessel containing liquid mercury that conducts electricity when it can flow to touch both contact wires. Explain how this device controls the furnace and how it can be set at different temperatures.

Long steam pipes that are fixed at the ends ofvqln*ib ey. a:n6/hk/ ten have a section in the shape of a U. l/an q*n.y:bhi6 v/ keWhy?

A flat, uniform cylinder of leaafc w9s;5 85aabv7foyu4t) wsd floats in mercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometer is first placed in a hot tub i.hqjce1ss:n;kv ; n;ulgo/ ; of water, the mercury initially descends a bit and th n.e;n;; 1j/l; h icsvgsqo:uken rises. Explain.

A glass container may break if one part of it isa jvfjlx 2qevqg7mw: * 29jo1, heated or cooled more rapidly than adjacent partsmg 1fv2e *jx 9oajvl j7:wqq2,. Explain.

The principal virtue of Pyrex glass is that its coefficient of ln4 ze7ux *q: ivxi9rp/ix9pp(v p w*9uinear expansion is much smaller than that for ordinary glass (Table 1 *7vpep(:zpui9/ir x9wvxnui 49qp*x3–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accur1xb ;)8d,t* pxh8afyjfe8h rcate 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 too - k(0sm6dffu6m7vaop to bulge so badly the can will not stand up. What 7skfdm (u0 mo 6ofav6-has happened?

When a gas is rapidly compressed (say, by pushing down a piston), its temper y)6y kru31 qwhvb;uswpg7,j 7ature increasebq7 )v1h6u3 7 pwj; ryuwsgyk,s. When a gas expands against a piston, it cools. Explain these changes in temperature using the kinetic theory, in particular noting what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force on an aluminum sphere wgkqyuiw1vc-*; wr-1submerged in water increase or decrease if the temperature is increase 1q;r kw- 1yuvw-c*wigd from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows f6,asn: h zcl6ze8 ;xvwrom kinetic theory and the relation betwe8;zxsc6zw v,ha:l e n6en average kinetic energy and the absolute temperature.

Explain in words how Gay-Lussac’s law follows 7pd:3 j(jg urvy,k1f tfrom kinetic theory.

As you go higher in the Earth’s atmosphgq5fp4j-/6fb cpys ,k ;oqxc/ere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for 7o aev-1 f9 6xjqr5mnlthe Earth refers to the minimum speed an object must have to leave the Earth and never return. Th7 lmqf1nx5-o6 ajrv e9e escape velocity for the Moon is about one-fifth what it is for the Earth due to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at room temperature. x x;nafmtsn:(kl *00tWhat can you infer about the molecular properties of one0ka tfxl0m(; s: nxn*t relative to the other?

Explain why a hot humid day is fwq cl.0 fc*heq q.5f7lar more uncomfortable than a hot dry day at the sa.llfc 7.q5qeq c*w hf0me temperature.

Is it possible to boil water at room tempe1 +x-h*2+c 4 eu6;neydwybe e5zzty rxrature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temp8tc2ojs* 1whxerature is the same but the humidity is different. Which i1oxjh 2 *tcws8s more dense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerous to sc8c*:e9/bc n 1xqyq h;d2-x(zwpxosopen the radiator cap of an overheated automobile ecsyd8;o x* /9qzec bx(nc-s:x 1 q2hpwngine.

Why does exhaled air appear 3e6b0ap,; )ppfjpdo ras a little white cloud in the winter (Fig. 13–28)?

  How many atoms are there in a hcs+ hp45 bzd 5/ib,fkvom-7 a3.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atomsf5z +f 8x3o8jml9na hg in a 26.5-gram gold ring compare to the number in a silver ring of the same o8l38fgh 5fx anm+zj9mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this on the Ccz 3xa)l p2bcjmb hb,9t6n5j ;elsius scale?3,tbmzjb h j 2;lx6 9anc)b5pc   $^{\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 recorded are z9/z5knux rkz- xx.+b136 $^{\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, ,q/)qktkc g)vjtg) n:the alcohol column has length 11.82 cm at 0.0 ,nq))/qtk )g :kvjtgc $^{\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 buill 2i)uioy.sl4tn5 i2 tt 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. 13–29) is built of wrought iron approximately 300 c s9rqa:+d m9m-tq4rj m tall. Estimate how qsd+r-rm9: 4tajmq9c much 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 that are nj v 5bl yuw3 n)2lft.dfgrzj4-3*q7blarger than the rivet hole are often used and the rivet is cooled (usually in dry ice) before it is placed in the hole. A steel rivet 1.871 cm in diameter is to be placed in a hole 1.869 cm in diameteb7)5fu lzb4j*fn r23y jvqtl.g3 wn-dr 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:leqyeio;b s9w3 ,75 d n9czvk at 4 $^{\circ} $ C is $ 1\times10^{3 }kg/m^3$ What is water’s density at 94 $^{\circ} $ C?    kg/$m^3$

  A quartz sphere is 8.75 cm in diameter. What wk064uij e5gdz19t. xr+ unprr ill be its change in volume if it is 19dr 6g4e50r n xujti+kzpr .uheated from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to th9 9t1bk6 t6fr j+tup-/cioilae 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 d7-ljbwx(.e t55.50 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 i8,im57k:f:nmz y7n zn0 vcrjcev;xe :n a ring made of iron. At 20 $^{\circ} $ C, the diameter of the plug is 8.753 cm and that of the inside of the ring is 8.743 cm. They must both be brought to what common temperature in order to fit?    $^{\circ} $ C
(b) What if the plug were iron and the ring brass?    $^{\circ} $ C

If a fluid is contained in a long, narrow vep dpi6x9/fm 7xssel so it can expand in essentially one direction only, show that the effective coefficient of linear expansion is approximately equal to the coefficient ofd9 67m fxxip/p volume expansion $\beta$.

(a) Show that the change in the densityy,:71 h1sdp 4tf m5bs ;uwfjej $\rho$ 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 ll6y kbc-jr9j1ld70alsi rm;, and width w has coefficient of linear expansjji6,1sd k9cy-rll0bm a r7 ;lion $\alpha$ 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 isotropicpy(24p x 2hbx)hza k0ua 2mjp; 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 gran3fo k(dkd79so dfather clock is made of brass and keeps perfect time at 17 kof(d 9d3kos7 $^{\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 mercb/,q/zm o mkr(6m7qi dg1k4njury thermometer has an inside diameter of 0.140 mm. The bulb has a volume of 0.mmrq4bi 6z/ kjod/(m1g nk ,7q255 $cm^3$ 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 cylinm+ozqct 316brdrical wheel of radius 0.41 m is rotating about its axle on frictionless bearings wo trbm qc6+3z1ith 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 desired length when at 15°C. How much stress 0d-hn+euznv9 n*zgu. nl9 p* vis required thl0 gpn*99uuve-. nznn d*zv+o keep it at this length if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I cwubx;lj6os 4aw7(rz(. oe2bxdl;/ o .0kssp-beam of cross-sectional area 0.041$m^2$ is rigidly connected to two vertical steel girders. If the beam was installed when the temperature was 30$^{\circ} $ C, what stress is developed in the beam when the temperature drops to -30 $^{\circ} $ C (b) Is the ultimate strength of the steel exceeded? (c) What stress is developed if the beam is concrete and has a cross-sectional area of 0.13$m^2$ Will it fracture?

  A barrel of diameter 134.122 cm at 201fx4;w u mmfn rn,e96z)0opuu$^{\circ} $ C is to be enclosed by an iron band. The circular band has an inside diameter of 134.110 cm at 20$^{\circ} $ C. It is 7.4 cm wide and 0.65 cm thick.
(a) To what temperature must the band be heated so that it will fit over the barrel? $\approx$   $^{\circ} $ C(Round to the nearest integer)
(b) What will be the tension in the band when it cools to 20$^{\circ} $ C?    N

  What are the following temperatures on the Keu 9tsyp r5:8-ivsn8c ulvin 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 whao8 ub*a.f0rc ;s. t6qexlm8lut temperature on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth 1nz 8eq n:nhfud+sb q4 w5m:g(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 atmospheric pressure and a temperat8ixiw2m ghl,amlejkqo--56 -ure o l -km-, g- q2l5owiemjhia6x8f about 20$^{\circ} $C is compressed in the cylinder by a piston to $\frac{1}{9}$ of its original volume (compression ratio = 9.0). Estimate the temperature of the compressed air, assuming the pressure reaches 40 atm.    $^{\circ} $ C

  Calculate the density of oxygen at STP using the ideal gas la 08 g3vwo3 le(c(fggzjw.    kg/$m^3$

  A storage tank contains 21.6 kg of niszurh8k0. + wl 9rhqg)aoa38dtrogen ($N_2$) 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 1t8trfk:t;a354 cu efg 8.5 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 heliuchv ie /0ivi9.m gas 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 1./4j4 i,e1ylu , /i9cj;m va;v btw alrvjqaj905.0 kg of argon gas at 385 jvtic/wlamy 9aeb /ja 41 ujq9r, lj,i;v;.4vK?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg f na 5-v+zlk6sof $O_2$ 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 sb: ( z5kjit/5gqca ++isb di4the balloon,gjtcd :s i+bk 5ai4/(zsb +5iq which makes it less dense than 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 ath-rgull/ y tbsabrmy1in -/aw4z2/-5 15 $^{\circ} $ C to a gauge pressure of 220 kPa. If the tire reaches a temperature of 38 $^{\circ} $ C, what fraction of the original air must be removed if the original pressure of 220 kPa is to be maintained?    %

  If 61.5 L of oxygen at 1h4d:;3 3 uwfq;vjemrv 8.0 $^{\circ} $ C and an absolute pressure of 2.45 atm are compressed to 48.8 L and at the same time the temperature is raised to 50.0°C, what will the new pressure be?    atm

  A helium-filled balloon escapes a chilmg+m7x .flw; ld’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 1w,s; ,ci zjy.ftadi,molecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there r24qw0bqmsvrqqx4 9 + in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of ()vs)gzzz:wh z q x+.1ikqcf9qb-l;7ya) moles,    $ \times10^{22 }$ moles and (b) molecules of water in all the Earth’s oceans. Assume water covers 75% of the Earth to an average depth of 3 km. $\approx$    $ \times10^{46 }$ molecules

  A cubic box of volume 5./5y e qxhb5zh0j*t:eu1$ \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 yo8peoa b+k*qs5gi6 m.ou inhale that were also in the last breath Galileo took. [Hint: Assume the atmosphere is about 8o *kse6bp5m og+i.qa10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average3:j.v+mqxr p3qrifua86gz g 8 translational kinetic energy of an oxygen molecule at STP? qa:gfxji.q v rrp 8363u g8+zm   $ \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 ofketd1 1m4 +zce helium atoms near the surface of the Sun at a temperature of abou km1 tze1e4cd+t 6000 K.    m/s

  By what factor will the rms speed ofrciz;j8fbh4xc+ 1, os gas molecules increase if the temperature is inc 4fibzhc1s8jcr,x+ ;oreased 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, g iem w lx 28i t5/njh0uvbi0y9m.:k6priven in units of km/s: 6, 2, 4, 6, 0miyhei2 k8.6 n/viul05 pwb0j tx9m:r, 4, 1, 8, 5, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of mole(pbj6u *yvzv6rd7g 7lcules 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 doubled while its volume is held constanttg; h7dss *ri+.vg1dt , by what factor doessdd.hgr; vti+g*s 17 t $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is -vl x i5b,eoi)vpn4b kei wo0-f9 :zm;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 mixtureouk6 vmroz0s0g8 p, v+p;+iejxnc9qq6m4d, w of two gases at the same temperature, the ratio of their rms speeds is equal to the inverse ratio of the square roots of their mow;0iqkrp c q +jdg4,uxzovm9, me 6 vp6on0+s8lecular masses.

  What is the rms speed h*j kyu)7pz.* lpzkuw6 g:kprnl-7 t+of nitrogen molecules contained in an 8.5$-m^3$ volume at 2.1 atm if the total amount of nitrogen is 1300 mol?    m/s

  Calculate (a) the rms speed of +rsy bgxo5t3if /r c7-a(;n5kd3ulrd an oxygen molecule at 0 $^{\circ} $ C    m/s
(b) determine how many times per second it would move back and forth across a 7.0-m-long room on the average, assuming it made very few collisions with other molecules.    round trips per sec

  What is the average distance between nitrogen moyp87cna9xc *jvks41c ) nfif(lecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed hs(6l9vgx vx: of an amino acid whose molecular mass is 89 u in a livgxxvv(hs6: l9ing cell at 37 $^{\circ} $ C.    m/s
(b) What would be the rms speed of a protein of molecular mass 50,000 u at 37 $^{\circ} $ C?    m/s

Show that the pressure 8n2(l 0qx lm-;ng h9wvqq 0ccgP 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 ur vxk 2vqq)p.+6,oyv3dcyab6d-5n zzy anium, $^{235}$U and $^{238}$U (the superscripts refer to their atomic mass), can be separated by a gas-diffusion process by combining them with fluorine to make the gaseous compound UF$_6$ Calculate the ratio of the rms speeds of these molecules for the two isotopes, at constant T.   

(a) At atmospheric pressure, in what phas *lfdm0f90d.y l zr-fa2w xc1zeq7qy 4es 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 ifbb smo0.:m 2c5ub-sas 0.01 atm and the temperature is (a) 90o a0bcb:b -mms 2.5suf $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity i i:r*-sv -irecs 50% on a day when the temperatuc r -isiver*-:re is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place wher7e51ezlbp4j(vx r( j;amfw,rjaeym59 j2 + oy e water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is 0.72 atmhpzo-dx ,nk )4f- k;hb, estimate the temperature at which water boils. oxp-fhz b kh; n-4dk),$\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of water bwww* l ebv5 psm.(3rb6z:-d, gh*tpwis 530 Pa and the relative zd5t mrh -w*.s,b3 wp*b: b(vlwwgp6ehumidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the temperature is 2/t(2 .ndwr orfss*t 2i5 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a 1u*ojay id kvfg0/w93b0 7cvh pressure cooker if the water is boiling at a temh*o w3c1vv7y /jg9 uf0dk bi0aperature 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 volume lw q/.;3hij*2ol aisi 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 point9j* xvx-muic8 8qqw3+kol1j 4;wli nrl1kq/v 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 glycinevpax(p;; lx:w dx6-gs)fr vo0 molecule (see Table 13–4) to diffuse a dista;xdarg) p:xs- ;pvw60vlo f( xnce 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 i)rvu zx4. :nj bnd9qg7nsects to the interior through tiny tubes called tracheae. An ave7gn4d.qnv )r:9jbxzurage 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 measur)wnis 51 f1xcke 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 calibrateor9h ao,g6(k3ij1 n h;buj(hk d 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. Hgv8pjz f8 yq*ez +4vqv 2o;zw*ow much error will be made in a recipe calling for 300 mL of cool water, ifefq8+2 vo*8q*w zpvy v;gjz4z 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 uv*.aa,) dzno28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of the original g.an,zv*)adou as remains in the cylinder?   

  Estimate the number of air molecules in a room of length 6.5 m,p dwiqg6 h0eys*g/jznn+ wat)q0:sn2 e+,r+p width 3.1 m, and height 2.5 m. Assume ze+i0s * 0ynwn:gw gdq2,6jqsthpp/ e+nra)+ the temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the den/+ 2mr-5n fr p1cnhqsrsity 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 atta8r4,klqipf hm0.q/gi / 8ugobinable using the best available vacuum techniques is about fl4r8pq i/ /i,kuo bggq8m h0.$10^{-12} N/m^2$ 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 w*3t jyn/weurfe/b 0mh idv-i./ zh5b) hen 10 m below the surface, to what volume would his lungs expand if he quickly rose to the surface? Is this adfm-e/r/twid/05ju y.3zh *hvebi )bnvisable?    L

  A space vehicle returning from the Moon entz zn(,igyo7e42 v4 nswers Earth’s atmosphere at a speed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this speed correspond to what temperature? (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 rwon 7vg,z (4s 4eiz2nyeentry.)    K

  The temperature of an ideal gas is increased from 110:jue3dy -o f2mh( mhik* jx/rh7i:g.x$^{\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 ofbb3kqshlzf7v5u xl.t86 u hb;2 5(wpr 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 Ear yjo;ip0c ku*.th, estimate the total numberki.;y* cpuj 0o of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contained in a 7.6 nm/ ykv/ajwl,lb1 o8(fcz)(b no9q x6$-m^3$ volume at 4.2 atm if the total amount of nitrogen is 1800 mol?    m/s

  A standard cylinder of oxygen used i vhn;hv-btms w:7a3p n/ -t 2bem7ln:an 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 atmospheric pressure, is constant at 2.4 L/mismva vlb/-7tnb 3a:eht2 n 7 ;wmhp-n:n. $\approx$    hour

  An iron cube floats in a bow 8m.4k l2/o k gx*7h3xh.bqmze1r2gxfoatj7cl of liquid mercury at 0$^{\circ} $C. (a) If the temperature is raised to 25$^{\circ} $C, will the cube float higher or lower in the mercury? ----待选择----lowerheigher 
(b) By what percent will the fraction of volume submerged change?    %

  The density of gasolnelef-*5d x e*i3 tq s4/8eifpine 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 . h6 9toyr.3fgry7 fmj25$^{\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 arr 5d-wn)k21sogf c, e glass jar at 20$^{\circ} $C. To help open the jar, it can be placed into a bath of hot water. After this treatment, the temperatures of the lid and the jar are both 60$^{\circ} $C. The inside diameter of the lid is 8.0 cm at 20$^{\circ} $C. Find the size of the gap (difference in radius) that develops by this procedure.    cm

  The first length standard, adopted in th(( qqa k2* /ji1gwh0lqkranelr 5; t.me 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 .1h lpws5lp ( ap6uv1fatm 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 E3 sq- c xlbq f69qn5psc/q3y5harth 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 t9 hx;gwre9bcor 0n8td fz*hm )n/)l. ehrown vertically upwx w m/;*8r9nho. 9)tlhdgfc z0b)ee nrard 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 (spherical) bubble of air fvqvx,9b-7 o mw, nfvk4rom a depth of 14.-vv97owvmqbf kx4 n,,0 m in a lake. Assume the temperature is constant at 298 K, and the air behaves as a perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total water/o(pe5 ugsjta)k),d,kmx ru2 nm7gm6 vapor pressure in the air on the following two days: p 7sd/2r5u,agt)emju)xg on6mk(k,m
(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 t+bn-x h+0sf1yty o t1she density of iron at STP, and when it is a solid deep in the+s+ n0to bh1f 1yxtsy- 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 gdtx0z5t e5 b.b :6llkshow that, for an ideal gas at constant pressure, the coefficientb tgkx5 :td .le60lz5b 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.