Which has more atoms: 1 kg of iron or 1 kg of aluminum? See ,sj /(2pupal ;p bndlc8.l1oa the periodic table or 8/j.lp u1lonsla (p,;b a2dpc Appendix B.

Name several properties of materials that could be exploited tfxt9;p.,x neqo make a thermometerf ,qn;tx .9exp.

Which is larger, 1 Ci( o6knv 5sj7i $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with systemk c xf)yclv:+o z/q92k B, but B is not in thermal equilibrium with system C, what can you s9kk2 vofz:q) ycx/l c+ay about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to a strip of iron. When h/qv+ f y- 7 pbvoagph*5,d)rteeated, the strip will bend. Which metal will be on the outside of r)5ed b ty+ 7fv-apvo/q ,p*hgthe curve? [Hint: See Table 13–1.] Why?

In the relation $\Delta$L = $\alpha$ $L_0$ $\Delta$T, should $L_0$ be the initial length, the final length, or does it matter? Explain.

The units for the coefficient of linear expaao: 0j dfrb6n:nsion $\alpha$ 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 v1y 3 zuf wnv:)9;p,obg;ced qthermostat used to control a furnace (or otzcd wbp)onguqv1:9yf v3e, ;; her heating or 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 often have a sec58d t) 1pnf2lmid lsy8lj5o-ttion in the shape of ln 1yt o tl5lpfs2-i5) d8dm8ja U. Why?

A flat, uniform cylinder of lead floats in mercury at 0n n)m rn/rob)b io/y-oe6m3r + $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-g*fu rncdg7q0r;i5-*blqus,yh o:ioyl1*e , in-glass thermometer is first placed in a hot tub of water, thn gcqr5iy*lg *, qr:;ih*-eub,dyo0 lf7 o u1se mercury initially descends a bit and then rises. Explain.

A glass container may break if one part of it is heated or cooled more rapidlyhteeo/y /aqoqsye629tt 7d-*in4ds : than adjacent parts. Expla d*e/e-is s /9nt7 htt24d6y qoqe:aoyin.

The principal virtue of Pyrex glass is that its coefficient of linear expansion 76ly ku97plfca7p*8n bl.u bzis much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistancekplp.lfb7 9u c 68b7a*7lu zyn of Pyrex.

Will a grandfather clo8,gf(vaku3 3xi;e eoa ck, 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 wilpxsq)2 oxwb9no t,8d 7l cause its bottom and top to bulge so badly the can will not stand up. What hasxsqxd,tb7) 98 p oown2 happened?

When a gas is rapidly compressed (say, by pushing ki+s c-3seah)9e;7tcbtkf .z down a piston), its temperature increases. When a gas expands against )tscbz+3akt.f7e;hc k -9i se 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 inyk 70l,:zlazll r).b9johq(lcrease or decrease if the temperjr:z,la l7l (ohqzly9k )lb0. ature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows frodgedp2)ti*2r m kinetic theory and the relation pe)td* d2 r2igbetween average kinetic energy and the absolute temperature.

Explain in words how Gay-Lussac’+*)zi ijrdy v.4bqkd ,ixch73s law follows from kinetic theory.

As you go higher in the Earth’oc750 p1jcqh+d)a a drs atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minhy7v5iesjr. m*ur ok6szp x7*: oo7w.imum speed an object must have to leave the Earth and never return. The escape velocity for the Moon is about one-fifth what it is for the Earth due to the Moon’s smaller mass. Explain why the Moon has practically no atmospo7o*siuphk7 zxej*sr ..:r 7y 5v6owmhere.

Alcohol evaporates more quickly than water at room temperature. What can you 19bvabg j2vix *wwbvp3,83hq infer about the molecular propertiep 8 ,x3qvwv1 g*bhb2j3a9vbi ws of one relative to the other?

Explain why a hot humid day is far more uncomf042yr fj4so+-k dxe wdortable than a hot dry day at the same temperature.+w-f ojsdy24r0de4kx

Is it possible to boil water6l wv3affk-qj6c( w f6 at room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the humis/sogf4t zern3 8 d)8idity is different. Which is more dense, th4/8fdt3n)e zo is 8gsre dry air or the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap of an ovg z*ic4:y iy7q 9hzko5erheated automobile en yz5*i 7k9co4gqyz:h igine.

Why does exhaled air appear as a little white c(f2gkfmfj:).)+ch xz8d rnb m loud in the winter (Fig. 13–28)?

  How many atoms are thereb3l9 kzv6uh msdn lsk),(*f0ze )tj2v in a 3.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compar qgqp;t*9h z( eg:hu0djwfn40q,o+ sse to the number in a silver ringwun q+( :*h,qe spg9tdhz0sfg 0;jqo4 of the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is oftdbw 4fh :t 4iuos;; 6.q zkpkr,q)gn6*v.mt tien taken to be 68°F. What is this on the Celsius scale?t )ktzsk ;r..4qqnihuf6,v :*pb ; 4otimg6 wd   $^{\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 arc 61v rzb /ev83hfl4bve 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 11.82 cm at/:8gb:kg.yxrdx zl 9z4 2deynzdmmo u(d.b*5 0.0 9 5.m.y*(rmgeok2udg x: 8dzzxdl:/zd 4bn yb$^{\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 slabsgas+6j3+ t(0edocluy fd0qvq9(. ly b5 zkx/d 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.e /f.m;jt 3.qgse1o wp 13–29) is built of wrought iron approximately 300 m tall. Estimate how much its height changes between July (average temperature of 25°C) and January (average temperature of mo ;q.. 1 /psjtf3wege2 $^{\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 araor 0t jkbqc3qf(4z( 6e 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 st4 atr(c03ofjbqk 6q(z eel rivet 1.871 cm in diameter is to be placed in a hole 1.869 cm in diameter at 20 $^{\circ} $ C. To what temperature must the rivet be cooled if it is to fit in the hole?    $^{\circ} $ C

  The density of water krrq v1j3 8j62m9zgf bat 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 8lw q:4rdi 75pp.75 cm in diameter. What will be its change in volume if it is heated from 3q w lp:57pri4d0 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350.0 mL of wb7f :ti nm(pwv5k*b c*ater 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 55.50sd9 0xige/rt7r1 jubw ,b2m ,h 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 pl fvt7y5enw j.g ld,4* ivj4om k:p1-ndaced in 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 vessel so it can exp+ 8a/--o 8(bijua uf rryiccnba.a+l ,and in essentially one direction only, show that the effective coefficient of linear expansion is approximately equal to the coefficien,ayrli a bc -/8cijruu(- fb.+ nao+a8t of volume expansion $\beta$.

(a) Show that the change in t21s)n lonu66szvvgm 1he density $\rho$ of a substance, when the temperature changes by $\Delta$T is given by $\rho$ = -$\beta$$\rho$$\Delta$T
(b) What is the fractional change in density of a lead sphere whose temperature decreases from 25 $^{\circ} $ C to -40 $^{\circ} $ C？

A uniform rectangular plate of length l and wyr, 6lkl.bx )+-upf fn9g-kx a6zc0oaidth w has coefficient of linear ex-6la. or px k un l)k-+fx9ygcbzf60,apansion $\alpha$ 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 iso2g(uvn;xt2 rs tropic 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 gr(qf,9 eck1kspc9c* made of brass and keeps perfect time at 1*c(1pf rq, kgs9 9ccke7 $^{\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 insclk*excm pci i+;h46j7x. wu8 ide diameter of 0.140 mm. The bulb has a volumej kmcic xh; i+48*p6ux.cw7 le of 0.255 $cm^3$ How far will the thread of mercury move when the temperature changes from 11.5 $^{\circ} $ C to 33.0 $^{\circ} $ C? Take into account expansion of the Pyrex glass.    cm(b) Determine a formula for the length of the mercury column in terms of relevant variables. Ignore tube volume compared to bulb volume.

  A 23.4-kg solid aluminum cylindrical wheel of raj.sfknp bc2( +dius 0.41 m is rotating about its axle onp +.c njbf2(sk frictionless bearings with angular velocity $\omega$ = 32.8 rad/s If its temperature is now raised from 20.0 $^{\circ} $ C to 75.0 $^{\circ} $ C, what is the fractional change in $\omega$?   

  An aluminum bar has the desired lengq5 xjcv(eo- h w,)o1rnkv;9+p dj ,0fysu wxg3th when at 15°C. How much stress is required to keep it at this length if the temperatuh) 9k wv(j+1j- xogr3uvxy;,csfn qe,wdp5 0ore increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steey:4iyahaa /p.l I-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 134.1.:ko hnroc1;dhp0t mo 14rv v8c4-luj22 cm at 20$^{\circ} $ C is to be enclosed by an iron band. The circular band has an inside diameter of 134.110 cm at 20$^{\circ} $ C. It is 7.4 cm wide and 0.65 cm thick.
(a) To what temperature must the band be heated so that it will fit over the barrel? $\approx$   $^{\circ} $ C(Round to the nearest integer)
(b) What will be the tension in the band when it cools to 20$^{\circ} $ C?    N

  What are the following temperatures on the Kelvin scpq3r0 +s j6ij77ssvsh ln:ex5ale:
(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 Fahren6 o5fkt+sk 8clheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth z+6zp qq5dzb9and 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 combustinr*imvv 4w bwq-cw z372ehq2* on engine, air at atmospheric pressure and a temperature of about 2iw*r4 n 3mv vc*2qe2wwb-7 zhq0$^{\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 lpy.0u sf0d )a ry;dc7at STP using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of nitrog elj.3f)ethc 1d*yj9oen ($N_2$) 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 1 q ;rlqj6yjr3.x0o,eigf1f3aaz6 z, i(alle08.5 kg of nitrogen ($N_2$)
(a) What is the volume of the tank? $\approx$   $m^3$(“Round to one decimal places)
(b) What is the pressure if an additional 15.0 kg of nitrogen is added without changing the temperature?    $ \times10^{5 }$Pa    atm

  If 18.75 mol of helium gas is at 10.0t,,sqn,7mr+sg 71 mr5yzh 2tan(xzac $^{\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 c2ryv1h pek*- wontainer holding 105.0 kg of argon gas at 3pe 2r*-1kwyvh85 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg o f jn km)+ )uh1zdryzy(,t*dln l1ym87rfag+(f $O_2$ gas at a gauge pressure of 8.70 atm. If the oxygen is replaced by helium, how many kilograms of the latter will be needed to produce a gauge pressure of 7.00 atm?    kg He

  A hot-air balloon achieves its buoyant lift by heating the air inside the y-z/di2ew pn5sl* +ipballoon, which makes it less dense than ths dnppw*yii e2 z5l-+/e 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 wit6 20mm icdjlh+h 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 atwgusk-w. f f02 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 escapes a child’s hand at ss.k1w pa)m6rqw 5lze :nd) mm)ea 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 mb;hu5gw 4 upc;47ux huolecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of waf2 ujd vk.5)leter are there in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (ha n*k7tly*n+wssxrwa eo).7n6h s + 1a) 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 rty2 +f ;i cr8xefm-5r5.1$ \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 inhale that ufva2 0*l9kpoirik3)mo(gx ;8tw zu1 were also in the last breath Galileo took. [Hint: Assume the atmosphere is ab8l1 i gu*vr0kzx(fim w9ok23o;u)patout 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of yeue 04tlbd)/q-dp.ran oxygen molecule at STP? q)b4r0l ete -/.dpuyd   $ \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 jyxn8/0:,zaesw z8 hp atoms near the surface of the Sun at a temperature of about 6000 K0z8s zh a8xjp/eyw,: n.    m/s

  By what factor will the rms speed of gas molecules 6r*q ;c uag;rvvql(,c increase if the temperature is increasq;6rcrv lg,uc q (a;v*ed 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 havk:sfn- kq(;p: .bntpqng 4di*sza* 0y e the following speeds, given in units of km/s: 6, 2, 4, 6, 0, 4, 1, pn- a.z:p:*4 snns*f d( gtqkkiqby ;08, 5, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at 2*ud 076jqw (bvwlgk2j0.0 $^{\circ} $ C is to be increased by 1.0%. To what temperature must it be raised?    $^{\circ} $ C

  If the pressure of a)5ed 3ga z1n7 v4 k.0jgiyru t0qcwz.o gas is doubled while its volume is held constant, by what factor tu.jgw. c)10onde0r 5v3zg 74kyq iazdoes $v_{rms}$ change?   

Show that the rms speed of molbq( 2ramhvwvfsro+p9h:l5p o *6fz qu3. (v:uecules in a gas is given by $v_{rms}$ = $\sqrt{3P\\rho}$ where P is the pressure in the gas, and $\rho$ is the gas density.

Show that for a mixture of two gases at the same temperature, thebf3flri f4ype*- )k j) ratio of their rf-f pi ek)3y4jrlb*f )ms speeds is equal to the inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen molecules contaiz5.izk nc,( y.q jxz txp+)y9ined 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 vei kv8k kc*rp lu93 s3b7*jy.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 di9 1iu eankgo-3l9nk h4stance between nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speedmw 6hv8 *5thwrawgqcqy3a9:2 of an amino acid whose molecular mass is 89 u in a living cr6wgcaq ah3q m:58v2 t9y*wwhell 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 a gas can be writte:gfb,bynj 9sfq . z1w jnt6+9c:sqz2tn 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,ke z*+jt -tw ex,xf 3:2eq2fxa $^{235}$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 phases cac w,rjjei3:v jolx( 23g+)sjsn $CO_2$ exist? (b) For what range of pressures and temperatures can $CO_2$ be a liquid? Refer to Fig. 13–21.

Water is in which phase when the pressure is 0.01 atm and theagt0 c 4/k/cug temperature is (a)cc 0ak t/u4gg/ 90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity is 50% on a 46x6puuyc d veyj2 .mct;m:h.day when the temperature is 24:j exc2pvm.66tu h;.cy dyum 5 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure athme ynx.+ egqq5s /p5+ a place where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is 0.72 atm, estimatdyeh/ y3gx nh3/ jpa 25(e(pene the temperature at which(yj2h /n y5g(ee/ eh33pndpax water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of wap vv+,l-o kogolh jji49q uu:m/5v0n*ter is 530 Pa and the ro-vnuu:j j0 v+gkvqp / 4*i,mh9lo o5lelative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when thesblwsknu ,xq+x iuu+xj a+29: (;dxg8 temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cooker ibd w2x zy)5f3-w;v 7zzbfv 4sqf the water is boiling at a temperatures f5wq)vw b34xzb;fd7 y2zv-z 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 volum pl jldmy q+fm;zioz(q124w) 2e 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 ,h2i*h 9wx3zcb sd)s p5 $^{\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 n47kuguhhq ll4amw2+;56ab gfor a glycine molecule (see Table 13–4) to diffuse a distance q4h;kuuw2aa hglmn6gb l54+7of 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 i7 ..f,ws9efjq2di tmz8r zj (to the interior through tiny tubes called trac,i(d2rf e qj 8i7zm9fs.t.jwzheae. An average trachea is about 2 mm long and has cross-sectional area of $ 2\times10^{-9 } m^2$ Assuming the concentration of oxygen inside is half what it is outside in the atmosphere,
(a) show that the concentration of oxygen in the air (assume 21% is oxygen) at 20$^{\circ} $ C is about 8.7 mol/$m^3$ then $\approx$    mol/$m^3$(Round to one decimal places)
(b) calculate the diffusion rate J,    $ \times10^{-11 }$ mol/s
(c) estimate the average time for a molecule to diffuse in. Assume the diffusion constant is $ 1\times10^{-5 } m^2/s$    s

  A precise steel tape measure t6zk0:udn j)d 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 measu+ sokixl5urmh(e(u 7(re 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 +xn0 g4 h-tk2w4esn mncalibrated at normal room temperature. How much error will be made in a recipe calling for 300 mL of cool water, if the water and the cup are hot, a ntk -nhs0wex4+n24gmt 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in a helium gfv l y(dbx7y+v2mx8i99hh59 mox0n rias 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 tyx fl8ivn0 5bdhi h 2v+(x 999mmyxo7rhe cylinder?   

  Estimate the number of air molecules in a room of length 6.5 m, (x . iccxgy-(rv6mz ,hwidth 3.1 m, and height 2.5 m. Assume the temperam(cyvx6c ,.r -h(gxz iture is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matte 0 te6suuo*ml/*flya,r 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 availa ssoe i v8wx+b 0hf7v//edgz,5ble vacuum techniques is about 0ve+ofv h8idbsw7g5x ,z//e s$10^{-12} N/m^2$ 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 the c2:kc )neqaj t:2om7y sc n::j2m kt)2eo q7yacurface, to what volume would his lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning fr,p2en fq9zva* ket9 slbn)1i- om the Moon 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 temperature? (Because of this high temperature, the nose of a space vehicle must be made of spe*9 l)1i n9epekfb a,zqs-v 2ntcial materials; indeed, part of it does vaporize, and this is seen as a bright blaze upon reentry.)    K

  The temperature of an ideal ghbfm(+ogm13um t0 qt;h, jxk0as is increased from 110$^{\circ} $C to 360$^{\circ} $C while the volume and the number of moles stay constant. By what factor does the pressure change? By what factor does $v_{rms}$ change?$\frac{P_2}{P_1}$ =    $\frac{(v_{rms})_2}{(v_{rms})_1}$ =   

  A house has a volume of 770m xg83jktk lt25$^2$ (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 th 5:73dxljbz ewe Earth, estimate the total number of air molecules in t:x3 jzle5bw7 dhe Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen 2rfiw kf 5-b;fk0;v7jsw6kjz 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 hasv4ou/a ob 22m7hc35arnwu9 ct gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the fl maroch/ac vo23ub479nw 5 tu2ow rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in pjo l5 k /a6s9z30fuzka bowl 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 gasoline at 0cti s4sqj/u 32iu1-csogd-1 vd l+su 4$^{\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 snuglyed5ta:kyy m *9 around the Earth’s equator at 25$^{\circ} $C, but then was heated to 45$^{\circ} $C, how high above the Earth would the band be (assume equal everywhere)?    m

  A brass lid screws tightly onvr 9rk+d x4 q.oje 4h3wu9bac5to 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, adoptekq/b0 7;za. r;eltcoq9lg in)d in the 18$^{th}$ century, was a platinum bar with two very fine marks separated by what was defined to be exactly 1 m. If this standard bar was to be accurate to within $\pm1.0 \mu m$ how carefully would the trustees have needed to control the temperature? The coefficient of linear expansion for platinum is $ 9\times10^{ -6}C/^{-1}$. $\pm$ =    C$^{\circ} $

  A scuba tank, when fully charged, has a pressure of :jkb/;wnuke 4 195 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 Earth is y42 7i88altx 0mg*t8mwptj btf6aoj 2$ 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 graviff.; ka)*t 6ofs3t jixty by tennis 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 kg and are thrown at 12f fx6 .so i3kattjf*;)m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter (sp49zv7q)gze dqt 8s/hka 0j jm+herical) bubble of air from a depth of 14.0 m in a lake. Assume the t8t0ms7 dqavh kze4/jzg+q9 ) jemperature is constant at 298 K, and the air behaves as a perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure in the air on theet m1uj/y8g.)cj1h6(ap fuga following two days: 16g m1ya .)f ujctjph(gau /e8
(a) a hot summer day, with the temperature 30$^{\circ} $C and the relative humidity at 40%;    Pa
(b) a cold winter day, with the temperature 5$^{\circ} $C and the relative humidity at 80%.    Pa

  A sauna has 7$m^3$ of air volume, and the temperature is 90$^{\circ} $C. The air is perfectly dry. How much water (in kg) should be evaporated if we want to increase the relative humidity from 0% to 10%? (See Table 13–3.)    kg

  Estimate the percent difference in the density of iron at Snws- 0j3b 3z,vsl+r5how 8ohd TP, and when it is a solid deep in the Earth where the temperature is 200 hd,vn-z0 35rwobjsw3+s lh o80$^{\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 v er :nzo0s5m7that, for an ideal gas at constant pressure, the coefv:7n0m reszo5ficient 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 their cella ikq fdu.udf.);2dr.kip74u v rs to prevent rot and mildew. If the ck ) .k dv.pr4uqid i7u.;2fufdellar in a house (kept at 20$^{\circ} $C) has 95 $m^2$ of floor space and a ceiling height of 2.8 m, what is the mass of water that must be removed from it to drop the humidity from 95% to a more reasonable 30%?    kg