Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodic table8nu2x)4xtg4p bd yty ja0y1*,mvba ,a or Appendixn4mt2ba0*y ,j)ay4xa1, xt8 gvpbudy B.

Name several properties of materials that could be exploited tj0 13 g4f,f:wjvfs-wpikdpo, o make a thermometerppw,:3 vs-j k1fdiw fogfj4,0.

Which is larger, 1 Cfm;cn44rqj4gay +pzer dj.ruw t gu34:jr.1 : $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium o69qygwj8u 5jwith system B, but B is not in thermal equilibrium oqgu6wy895jjwith system C, what can you say about the temperatures of A, B, and C?

A flat bimetallic strip1az*tfdm 5 h45cn5wg t consists of aluminum riveted to a strip of iron. When heated, the strip will bend. Which metal will 4mdzgwct a1f5n *5t5hbe 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 9q7h; a hsg *ma9n zhac /0t3-ydb(eviof linear expansion $\alpha$ are $(C?)^{-1}$ and there is no mention of a length unit such as meters. Would the expansion coefficient change if we used feet or millimeters instead of meters? Explain.

Figure 13–27 shows a diagryg)zj* s7xve ixg0 4;ram of a simple thermostat used to control a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch is a glass vessel containing liqi);sjz yv0x7x4gr*g e uid mercury that conducts electricity when it can flow to touch both contact wires. Explain how this device controls the furnace and how it can be set at different temperatures.

Long steam pipes that are fixed at the ends often have a section in the shag4t c8r ks1poinl0,4bpe of a gl8p 1k ,ntcs4b0oir4U. Why?

A flat, uniform cylinder of leaj2h gbv:/ mk6od 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/ayt5;y pqyf d lrtb18* in38c is first placed in a hot tub of water, the mercury initially descends a bit and then rises. Ex5qc8 tfplyy*a n1 tb;/ 8idr3yplain.

A glass container maycbpra2bsy yi5 +yu 9ayc 0zxi0 u30,,t break if one part of it is heated or cooled more rapidly than adjacent parts. Explat z2 yc0u p3y09a+u ayib5yib, s,0rcxin.

The principal virtue of Pyrex glass 7:q.aqpg+ y+-+r+vt7i+pb4 zpf kf gtjlin3x is that its coefficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the incr+pf lv gryz t+ga qq -:pjftp+n++kb7ii.x374eased heat resistance of Pyrex.

Will a grandfather clock, accu 7n)r4/ oakkqhrate 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 thn1mb1zi 57( mtngktwv, 2+rjk c8kmf)e can will not stand up. What has happened?vm1m 1mnz),(f5kgktb7nrw k2 i+c jt8

When a gas is rapidly compressed (say, by pushing down a piston),x97**a6b)r p nt tsosl its temperature increases. When a gas expands against a piston, i76ras lx*sot *t9)pb nt 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 z-jm d. x2zrw;water increase or decrease if the temperature is increasdjx z.w-zr2m;ed from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charlesmx 2ogb, rds 7 df) i4ua5z:xqu:s0t2w’s law follows from kinetic theory and the relation between averagexg2q5ubi xdmw0ua7 s :s, o: 2rt)zd4f kinetic energy and the absolute temperature.

Explain in words how Gay-Lussac’s law)1 wu2oibnkhoi g6b. 0-iesv: follows from kinetic theory.

As you go higher in the Earth)(:h g xkux3ozfglsrl .d 0*w8’s atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Ear8hoyd8 rc,lr wgtytj/(0u1 , rth refers to the minimum speed an object must have to leave the Earth and never return. The escape velocity for thtyr rj8 w0/uh8g,oy l, cdtr1(e 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 -3wo am fkg,/-8gdv umthan water at room temperature. What can you infer about the moleckf3 -mg o d-uw8/mgav,ular properties of one relative to the other?

Explain why a hot humid day is far more uncomfortable thztosd1u p.so-2a ;hcnrfp + +5ct i30oan a hot dry day at the same temperppt0;t1ooss+na 2hor c3c-.dz+ufi 5ature.

Is it possible to boil water at room temperature (8ew dt7++o1w b5cembze 0man220 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same bu+4lvnm.+qcqaefv98qbqycm* -0* ie6jnbk z3t the humidity is different. Which is more dense, the dry air or the humid air at the samf *3ec-zmy +bq0n qe9*b.4qi l 86k+naqvmcjve T? Explain.

Explain why it is dangerous to open the radiator cap xs5. a+3 ziozb7i l*vht;dq3i of an overheated automobile e3hti7qia3*o .vzd 5;x blisz+ ngine.

Why does exhaled air appear as a little white cloud in the winter (Fig. 13–28)y.e v z9+kw(kb?

  How many atoms are there in a 3.4-gram copper dec/8blmgf-9 penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring cof,apd4;h on:y+xvcs5d /bl9 i e 8/rwnmpare to the number in a silver ring of the dvrcxoyw+sh:/pd4 na95l8 e/i n, b;fsame mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this on the Celsius scal(w(jdw nd r:0xe?dx((r:w d0wnj   $^{\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 tl(2(4i5hcag ; hlg duaw10 b wipli3w /ayd+v+emperatures recorded are 136 $^{\circ} $F in the Libyan desert and -129 $^{\circ} $F in Antarctica. What are these temperatures on the Celsius scale?high =    $^{\circ} $ C
low =    $^{\circ} $ C

  (a) 15 $^{\circ} $ below zero on the Celsius scale is what Fahrenheit temperature?    $^{\circ} $ F
(b) 15 $^{\circ} $ below zero on the Fahrenheit scale is what Celsius temperature?   $^{\circ} $ C

  In an alcohol-in-glass thermometer, the alcohol column has length 11.82sl8az9nvjdf v6 .h66u cm at 0.0z6dnfh 9v6us6jav8l. $^{\circ} $ C and length 22.85 cm at 100.0 $^{\circ} $ C. What is the temperature if the column has length
(a) 16.70 cm,    $^{\circ} $ C
(b) 20.50 cm?    $^{\circ} $ C

  A concrete highway is built of slabs 12 m-i+;m* gvbxvjco)h/v 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. 13–69:lpm zflbx 08sb+0z- ywqyv29) is built of wrought iron approximately 300 m tall. Estimate how much its height changes between July (average temperature of 25°C) and Januaryxzp0lw89b:ql0b y vy6-m+s fz (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 lgt6t*2 8ohl l7rp;qx q )lh4kparger 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 dia4kl*htg2lh xr; q8l o )6qp7ptmeter 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 at 0 olcxqi29x8v2ewskd;elgb.s 2 gv 644 $^{\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 volume i8b *hta/tmp1 q0jw m0vf it is heated from qpw/tm1j8v ha t0mb0 *30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350kna ) ahp;)jxynz;yec4-b1 9y.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 at 2;ip(zll72j xb 0 $^{\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 (5io+u icvs *ulesubg8mz1 fju,/,-h iron. At 20 $^{\circ} $ C, the diameter of the plug is 8.753 cm and that of the inside of the ring is 8.743 cm. They must both be brought to what common temperature in order to fit?    $^{\circ} $ C
(b) What if the plug were iron and the ring brass?    $^{\circ} $ C

If a fluid is contained in a long, narrow vessel so it can expand in essentiallyi +r8gpdilp/ 3k1u1u k one direction only, show that the effective coefficient of linear expansion is approximately equal to the coefficient of volume expa1li+/1p dk3uuirkg p 8nsion $\beta$.

(a) Show that the change in the densg *ucpmwwsp c44.80z8tc4: l7tzh(y wsqkb3x ity $\rho$ 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 rectangularjk1 ep hrw,qms,e/mi2 wy0 r3) plate of length l and width w has coefficient of linear expansion wqm,, sr my/rkj1 w0pei)he32$\alpha$ 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 isotro9a)7wtkp +)qxb5kru w pic solid, $\beta$ = 3$\alpha$ if the amount of expansion is small. $\beta$ and $\alpha$ are the coefficients of volume and linear expansion, respectively. [Hint: Consider a cubical solid, and neglect very small quantities. See also Problem 18 and Fig. 13–30.]

  The pendulum in a grandfather clock is made of bb) pu bs:qkcbo:r8u+4rass and keeps perfect time at 17:c purk q):8oubb+b4s $^{\circ} $ C. How much time is gained or lost in a year if the clock is kept at 25 $^{\circ} $ C? (Assume the frequency dependence on length for a simple pendulum applies.)$\approx$    min(Round to the nearest integer)

  (a) The tube of a mercury thermometer has an inside diameter of 0.140 wiwckq.,+3dq mm. The bulb has a volume of 0.255.dqq,w+icwk 3 $cm^3$ 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 wheeta21, rxpdk* ;jq kxh2l of radius 0.41 m is rotating about its axle on frictionless bearings with angular velocity 2tpxaxjr 2;,dk*1qkh $\omega$ = 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 wz6mt; hj5 get7hen at 15°C. How much stress is required to keep it at tj5 gt7;eztmh 6his length if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-sectional area5bo+;hon v5x bd+sc6f 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 2r gn3vjh4l-v9 0$^{\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 lh4zi 8dt c:-bx/gd5 ctemperatures 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 temperature on the F6 a g48/r7wwoa h0lymr;,ixdxahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the in;*3do-mltdn mk: sflj2w+vm1q8 ism3terior of the Earth and Sun are about 4000$^{\circ} $ C and $ \times10^{6 }$ $^{\circ} $ C respectively.
(a) What are these temperatures in kelvins?    K    $ \times10^{ 6}$K
(b) What percent error is made in each case if a person forgets to change $^{\circ} $ C to K? $\approx$    %(Round to the nearest integer) $\approx$    %(Round to three decimal places)

  If 3 $m^2$ of a gas initially at STP is placed under a pressure of 3.20 atm, the temperature of the gas rises to 38.0$^{\circ} $ C. What is the volume?    $m^3$

  In an internal combustion engine, air at atmosph 26cjgr)wh+jww y:1lpnnd2v- eric pressure and a temperature ofn22w-c+wrgw :pl6)djny1 hjv 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 if(6b i 3h/smhgdeal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of nitf4:-b f+e mswprogen ($N_2$) 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.a );mf5smw ,kz5 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 is at 10.072d xb/ubxt9s :nnt p+$^{\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 containerkkigyd 64xc2, holding 105.0 kg of argon gas at 38i2 ,kkd6gycx4 5 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg ofmnw + ,bg+evq(yah 6h6 $O_2$ 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 insi v2f:sy okfq;b1.iu-ade the balloon, which makes it less dense than the air outside. Suppose the volume of a balloon is 1 vfu;sf2a1:yq k-.o bi800 $m^3$ 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 withhd4 w9z-j :31y 1 jygklbtfy3j air at 15 $^{\circ} $ C to a gauge pressure of 220 kPa. If the tire reaches a temperature of 38 $^{\circ} $ C, what fraction of the original air must be removed if the original pressure of 220 kPa is to be maintained?    %

  If 61.5 L of oxygen at 12n;c.bzwa ;he 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 escap1ajqook9ar3- n+m8;8ew a;ovpj8b d jes 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 moleculad))vz-rcnh 1 irbg(p/j zq) 3es / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How many l i ro*xi)kspj1,7m f1k22pfcmolecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) mo9vngdb7a gwt3146n 8prr x8hsles,    $ \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 volumelqvz9e4 g *3.9tjj+gn bzwv 0c 5.1$ \times10^{ -2}m^3$ is filled with air at atmospheric pressure at 20 $^{\circ} $ C. The box is closed and heated to 180 $^{\circ} $ C. What is the net force on each side of the box?    N

  Estimate how many molecules of air are in each 2.0-L breath you inhale6(gn/jdch/ mem *r)o0qlc fweg pp:;* that were also in the last breath Galileo took. [Hint: Assume the atmosphere il w/ h;*nercp)0pegqm mgc*f/o(: jd6s about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translate zm,gu; rfj:iz(q78n ional kinetic energy of an oxygen molecule at STP? r8em7 nzu,(zq:;fjgi    $ \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 at7dotkmvre02b r ,- f z6jz99ti a temperature of about 6000 Kbtfo0z,i-9 v dz7r 2k6rtem9j.    m/s

  By what factor will the rms speed of gas molecules increase if the temp4 xf*vd7bl85d/+5 -.yrqk rroxpfsh+xb/ olnerature is increased frofpvob 5hsx.k*4- n5q7xr dr/bf/+oyd+ rlx l8m 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, 3j lk gq 3wb7zcf+*h0v4, 6, 0, 4, 1, 8, 5lwqcj +k7*bz3vfh3g 0, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at 20.0er5 wkq) tb 9;sd ucok69*jv:i $^{\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 :mxub yn5f*neqs4m ( 8its volume is held constant, by what factor ( :4sm efqy58nmu*xbndoes $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is given by 92xvuzues6 w:zc:l 1z gv2 h/f$v_{rms}$ = $\sqrt{3P\\rho}$ where P is the pressure in the gas, and $\rho$ is the gas density.

Show that for a mixture omh9664ny4 hzswah jy7f two gases at the same temperature, the ratio of their rms speeds is equah64hazh4ys9 mj6wny7l to the inverse ratio of the square roots of their molecular masses.

  What is the rms speedo6rqp w4y*hoq6* hbk* 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 an oxygejz.d ;v5( g515axkgn 3djwxrzn 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 :(h4rg affe2)*cz i no22a prnmolecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of ecl7d7*c:e;mn tm,a wan amino acid whose molecular mass is 89 u in a livi*weeccl;mm 7 n ,d7at:ng 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 P of kk8: jbm7k -k j6bjb+ja 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 ura3(goo;p 5ec6x1/dqu;pol kn t nium, $^{235}$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 ph4wl;/wmb tbes,) .j3 m6vnsl(bgkf;ressure, in what phases can $CO_2$ exist? (b) For what range of pressures and temperatures can $CO_2$ be a liquid? Refer to Fig. 13–21.

Water is in which phase when the wlpb12c2f 0vqx/fub-+ //h idm3c ltjpressure is 0.01 atm and the temperature is (a) jxm0q c+b 1vb22dhpu w///tc3fli l f-90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if1.a dl, ;n2fjl8jx cx.:jliyb the humidity is 50% on a day when the te8nly lf2 jxi ,dj. 1c;l:ja.bxmperature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a placaim)/e7v*vow2 k ebz au2v*v)e where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mo6;*c ;tp dd2k yi+knsnn1lqw ,jo7*ti untains is 0.72 atm, estimate t ;n*sop7nw1;q j it6dildk*, cnkyt +2he temperature at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the yz(kyc)km 6(vs o060adwuc c 0/dqq3 zpartial pressure of water is 530 Pa anak y(qy3cvc /d0(owmsz0 6qzc)udk6 0d the relative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on aq a (++kog5ft/-xcxtp2 m n8hizq2o/p day when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cooker if the wz)ybpk4orwpp 5v.u- ugg.h +0 ater is boiling at a temperaturwou-u 04gyb5.ph.g prp) kvz+e 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 o7-01;pusvpx-wjoz iexs / z czv 322zyf volume 680$m^3$ at 25 $^{\circ} $ C is 80%, what mass of water can still evaporate from an open pan?    kg

  Air that is at its dew point of-fv6ghx4di r( 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 molecule (see Th6h ujdd2w*c +bxl.*u able 13–4) to diffuse a distance of 15 6*jxlcudb*u .+hdh2 w$\mu m$ 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 il)ph7;2crb e unsects to the interior through tiny tubes called tracheae. An average trrlc)bu;7e2ph achea 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 measurepodhcv(m n4al *c:jru + 2,vwq6 gj7o/ 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 calibry2durnt+n/ps+(6m8rqzd3p w ated 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 calibra, 81wm1;qh swq ,m*nppln1hcbadk +a. ted at normal room temperature. How much error will be made in a recipe calling bmp 18h.whan kq m;l,,s11*+a cpnwdqfor 300 mL of cool water, if the water and the cup are hot, at 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in a helium gas cylinder is initially 28 atm. Aft(bkvidpbz,:+zq33h f/hu; z ier many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of the original gas remains in the cylh/,ifzvb3 3 ;phq buz(i d:kz+inder?   

  Estimate the number of air molecules in a room of length 6.5 m, wibw:v2: uxzav+ *fetp *dth 3.1 m, and height 2.5 m. Assume the temperatx:uf+p vwzvtba:2 *e *ure is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of mac0i fls w/hknnv o2, p/ls-p+ct..h ,vf0io/ ntter is about one atom per $cm^3$ mainly hydrogen atoms, and the temperature is about 2.7 K. Calculate the rms speed of these hydrogen atoms, and the pressure (in atmospheres).$v_{rms}$ =    m/s    $ \times10^{-22 }$ atm

  The lowest pressure attainable using the best available vacuum s 6s;a5p ; e1uy;g5um x;wgmeqtechniques is about 6 sex;qmu ;psegm ;;a1ygw55u$10^{-12} N/m^2$ 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*0uti 0vi nog:g8my*p gmt y-* 5.5 L when 10 m below the surface, to what volume would his lungs expand i*u8mgym:gy0-i *tn g ti op*0vf he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Mb0zpu mjfw2 ohni1y4 o *y7h38oon enters 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 tum 284j0ow* yzb n1pfohi7h3yemperature? (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 from 110k+0 qq 3yf,6uiif3e 6po+/oj:omk)mv z5 kbxh$^{\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 ykuypj m *h;:9770m$^2$ (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 at-d;amkddv1b d0 mp7 s.mospheric pressure at the surface of the Earth, estimate the totm-kmp;0vba. s7d d1 ddal number of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed oc9 z8 46 snq+glyep,3i v1elvpf nitrogen molecules 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 (qn0g3lr,duz zfa2(m113,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure2fd(3 lg u1 amq0nzrz,, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liquid mezzfndkjj r4)qt6o/ l) e7 zfd0,+qj*srcury at 0$^{\circ} $C. (a) If the temperature is raised to 25$^{\circ} $C, will the cube float higher or lower in the mercury? ----待选择----lowerheigher 
(b) By what percent will the fraction of volume submerged change?    %

  The density of gasoline ihx(,x gqv2z30faum5 k hi)6g 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 atl:g5lby+0 nk x 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 ti-z:+ffqzdo/(iw pdele4 t,x4d a y+ j7ghtly onto a 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 thesb+o bd u3qdw.v 75.qn 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 pressuv 9hnw,j z6rpjcc5ma tjv 2vi84o 4,v0re of 195 atm at 20$^{\circ} $C. The volume of the tank is 11.3 L.
(a) What would the volume of the air be at 1.00 atm and at the same temperature?    L
(b) Before entering the water, a person consumes 2.0 L of air in each breath, and breathes 12 times a minute. At this rate, how long would the tank last?    min
(c) At a depth of 20.0 m of sea water and temperature of 10$^{\circ} $C, how long would the same tank last assuming the breathing rate does not change?    min

  The escape speed from the E)bhyn.ov :eu 0arth 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 suspem2tq 1qwz w;r)nded against gravity by tennis balls thrown vertically upward at it. How many tennis balls per second must rebound from the lid elastical2 z;qmtw1)qrwly, 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-diametep 8p/w72xeqyfr (spherical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and/fqwypep7x8 2 the air behaves as a perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure in the air on the followvq50d3q, uj xging two days: u5gjdx3q0 vq,
(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 densidwd:66kd w6hzty of iron at STP, and when it is a solid deep in the Earth where t6kw zd6:6 ddwhhe temperature is 2000$^{\circ} $C and under 5000 atm of pressure. Assume the bulk modulus (90$\times 10^9N/m^2$) and the coefficient of volume expansion do not vary with temperature and are the same as at STP.    %  ----待选择----decreaseincrease 

(a) Use the ideal gas law to show that, for an ideal gas at constant pressure, txp it wnfl/,/:5we d nnx,u9.ohe coefficient of volume expansion is equal tp ut lx,,.:f einx/nw/9d now5o $\beta$ = 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 dehumg dn5 c73+m3bbx3fvn tidify their cellars to prevent rot and mildew. If the cellar in a house (kept ad7f mtbbvcgn3x3+3 n5 t 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