Which has more atoms: 1 kg of iron or 1 kg of aluminum? ufk * pooldi*y+9i1: e at1p5kSee the periodic table oakoe9 5+po * t fiyi:l1du1*pkr Appendix B.

Name several properties of materials that could be exploited to make).cd 4hb zf;pc a thermomet;f4 ).p dcbczher.

Which is larger, 1 C h1bu6gj33ihez i m;t8* tp.bq $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with n x ,p1l2-hund-7itjpsystem B, but B is not in thermal equilibrium with system C, what can you say hnli-1x2t,n- udjp7p about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveteduh+lf*xxd ,i *g r5kh/ to a strip of iron. When heated, the strip will bend. Which mel*5 + *xudgkh/r,ixfhtal will be on the outside of the curve? [Hint: See Table 13–1.] Why?

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

The units for the coefficienl6tlcmt lwd*d r2- z13l8cmgo r/y- b8t of 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 diagram of a simple therl1;. 8j,vqkp0 zyftho mostat 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 liquid mercury that conducts electricity when it can flow to touch both contact wires. Explain how thozph k80f.j; qvlt,y1is 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 the0b: kusgi hii* *.p+jr shape of a U. Whyrui* kh+g*isbi j:0p.?

A flat, uniform cylinder of lead f92bon/kd jo, oloats 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 firag18zg v8tbkp(f .f0sst placed in a hot tub of water, the mercurk b. f(af8p8g1ztv0sgy initially descends a bit and then rises. Explain.

A glass container may break if odil-vvl -+q6 cne part of it is heated or cooled more rapidly thanl+6v- -dlvqic adjacent parts. Explain.

The principal virtue of Pyrex glass is that its coefficient of linear expansio3 qrmh 9c*hhnqpch obu 3wh2 m 0tqv1/6ey:2o+n is much smaller than that for ordin3hqt3oobh *u61:qhch/q h wep2v2y9 mmcn +r0ary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurate at 20 0vw:8 m0fdq f-*vjwjm $^{\circ} $ C, run fast or slow on a hot day (30 $^{\circ} $ C)? Explain. The clock uses a pendulum supported on a long, thin brass rod.

Freezing a can of soda will cause its bottom and top to bulge so badly the cangfw )lf/l+:foe x2 e:w will not stand up. W:e+ wwfg2l /exof) f:lhat has happened?

When a gas is rapidly compressed (say, by pushingolp-6(.aa :s zg: ljni down a piston), its temperature increases. When a gas expands against a piston, it cools. Ea(jla .p-os:6 l:giznxplain 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 pvb 14;y:oc7f xyc csg1 f6uk:sphere submerged in water increase or decrease i4sc7 yp1fo fbu6yxv;c :k1c :gf the temperature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kip hi+i6rsj c:4em-*ser-hsvz q+l k:mjd9;z3 netic theory and the relation between average kinetic+vej6s 4dis9z; rlhskz*j +:-h:c -rqmp mei 3 energy and the absolute temperature.

Explain in words how Gay-Lussac’s law follows froyy 1 3gfw.pxv4m kinetic theory.

As you go higher in the Earth’s atmosphere, odl;j1(ss 2pbthe ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minim*l w2awcqdya77 + v7zs6 j6bawum 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.c7d wzybsw w26vq77aa6a jl*+ Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than wategm-q-uf 9hutj3-a y1wr at room temperature. What can you infer about the molecular properti-jh 9wfmqu-u-g3yt1a es of one relative to the other?

Explain why a hot humid day is far more uncomf)cuj2no9oh y sv (coqcmg-/95 ortable than a hot dry day at the same temperahso )9nu-2(vccyjg5c/ 9qo o mture.

Is it possible to boil water at room temperature (2is)wa:6p.4o aht g 6xa0 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperatu b6e:x2m;g wbtk5o7 psre is the same but the humidity is different. Whi e :bx5sp2ot6kwm7 g;bch is more dense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerous to -ex,j;m ed)bcpz h l2e*.el5qopen the radiator cap of an overheated automobile engeeqz.lde2)c mb;*-lex,5 h pj ine.

Why does exhaled airn fg); u6 7qo +yrc8w*dqy8vqf appear as a little white cloud in the winter (Fig. 13–28)?

  How many atoms are th9 lc) s,pa0jfoere in a 3.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-grat9-wzkj 4x:fx ((mpo fm gold ring compare to the number in a silver ring o(zp:t49k xxfm jo f(w-f the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What)si(er;nu+ 8d+yppnn is this on the Celsius scale?p( nud ; iy+r+enspn)8   $^{\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 rekdd+0 cnga; fq- 6(ayncorded 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.ir ; cpa6nmys-jo)r y5ryi ,3 alcohol column has length 11.82 cm at 0.0 )irp,.ncyjor;5 ya-yi mrs 36$^{\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 slabd 96nl::ioibzr(q7vb(jt ic1 s 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)us 6vp* l2qrz( is built of wrought iron approximately 300 m tall. Estimate how much qu *lz 62sv(rpits 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 vorcfocx)n gkm-b(1qm+qjye93/ 5*p that are larger than the rivet hole are often used and the rivet is cooled (usually in dry ice) before it is placed in the hole. A steel rivet 1.871 cm in diameter is to be pla+5m x efvk1 o q9rc3g*jn)(qyomc-p/bced 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 x;**u f-5,nm dveb/) ehs uhwx4 $^{\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 i y;:m2laa sva8*0ywst f it islm0as y;s2wa*8:t vy a heated from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to/uwcvnw s kg(d b;11:p the brim with 350.0 mL of water at 100.0$^{\circ} $ C. If the temperature decreased to 20.0 $^{\circ} $ C, how much water could be added to the glass?    mL

  It is observed that 55.50 mL of water4hwpd qks )r 0hv s3a7m9jc949yod;ky 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 iq2jque ngzbm/0+no+ 3zae -.p w1 /vwan 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, nar8i cegfysg79 ;row vessel so it can expand in essentially one direction only, show that the effective coefficient of linear expansi7c;8feg is9 ygon is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the ay-1 z bmftl/: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 wv ja(x*, znwl-hbz9,fidth w has coefficient of linear expanb zhf l-vj*,awz(nx ,9sion $\alpha$ Show that, if we neglect very small quantities, the change in area of the plate due to a temperature change $\Delta$T is $\Delta$A = 2$\alpha l w$$\Delta$T See Fig. 13–30.

Show that for an isotropic solircrz(owk ayh15+2s2g d, $\beta$ = 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 brass and keeps pe(vs0bd -/cih h(hkn .frfect time at 17 svkhbfh.- 0/ih((n dc$^{\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 h5pq09cy /qn si .jix:of 0.140 mm. The bulb has a voipq 9qsc0yh. xi/ nj5:lume 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 cylin olxwpxcw )-s3kn:q8 4q ui 89pug00fzdrical wheel of radius 0.41 m is rotating about its w )liqnguus:4 k-q9c w830o 8 fpzx0pxaxle on 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 thetjp- mo/b1 answ.7 uz0eri*/ g desired length when at 15°C. How much stress is required to keep it at this length if the temperature in-e7ug/ *pw1 . oisa0ztj nbrm/creases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam proi ;s53wna xl693ncof 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 2q0znkq3(*je y0$^{\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 followin ) fs:t3rptms2g temperatures 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 Fahrenheit scale?9gomj8zp:c.zf2r c 5q18ws enu m 2ee3    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun are about 4000 gejjwq)(-9, yv gp)hm$^{\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 combustiong fo55x*id.u5xwnog2x w775etkb: ld engine, air at atmospheric pressure and a temperature of ab52e b7g5.o5dd lk:x ngow*ft xi5xw7 uout 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 usbxpwt9 sqd9 y 2k+:f9ying the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of wfy rl4tgs(p)ux7g oel(s 2 *(nitrogen ($N_2$) at an absolute pressure of 3.65 atm. What will the pressure be if the nitrogen is replaced by an equal mass of $CO_2$    atm

  A storage tank at STP co-jlx 5p i7: fm)z)pvuqntains 18.5 kg of nitrogen ($N_2$)
(a) What is the volume of the tank? $\approx$   $m^3$(“Round to one decimal places)
(b) What is the pressure if an additional 15.0 kg of nitrogen is added without changing the temperature?    $ \times10^{5 }$Pa    atm

  If 18.75 mol of helium gas is ato5ylzqae5*n 3 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 ins//ge2 onvr .myjhwhh61:n + qfide a 35.0-L container holding 105.0 kg of argon gas at 38whrf /+q/6y2j. o v:he1 hgnnm5 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 k kj2-p1ona 9ayl2o,hmg of $O_2$ gas at a gauge pressure of 8.70 atm. If the oxygen is replaced by helium, how many kilograms of the latter will be needed to produce a gauge pressure of 7.00 atm?    kg He

  A hot-air balloon achieves its buoyant lift by heating the air insz hj jb 7u)yt5ov j5p.t1xk)dn0m/jq5ide the balloon, which makes it less dense than the air outside. Suppose the volumeoynudpbjj)7)tqv 05kh 5m/j j51.t zx of a balloon is 1800 $m^3$ and the required lift is 2700 N (rough estimate of the weight of the equipment and passenger). Calculate the temperature of the air inside the balloon which will produce the required lift. Assume that the outside air temperature is 0 $^{\circ} $ C and that air is an ideal gas under these conditions. What factors limit the maximum altitude attainable by this method for a given load? (Neglect variables like wind.) $\approx$    $^{\circ} $ C(Round to the nearest integer)

  A tire is filled with air at 15 -cl-29ami bda $^{\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 aqq3dz k)h) an8ojda*-t 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 chisiod j2t jqh):46d5:bunj -gdld’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 o x/dreeh2n6)( *ta g1szy 7bxgf molecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L?2 zq, 220unfyrq(cs ,asstb )w How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) molesyu srv fene9wu/s)x4fj 13.2t,    $ \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. xn 5i*wn/j znnhbug h2l9u(//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 molvj o2 .3tp5kay zx6o /yc7+(b6edbpsh ecules of air are in each 2.0-L breath you inhale that were also in the last breath Galileo took. [Hint: Assume the atmosp th vxke(c/.3 zy2 osdpbjo6a7by p+56here is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kineticyrji+, mw 3ah+u; n6qr energy of an oxygen molecule at STP? um36 ja+rnhq;iy ,rw+   $ \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 at avs . 4mqyx wgx1;cc/1e temperaturex1c evsmg1; qw4yc.x/ of about 6000 K.    m/s

  By what factor will the rms speed of gas molecules increase 5yfi(nfbad co b)0o,f(4y(gmjm 7; hxif the temperature is incj7;0a yfm( m)ox4yd hbffnb (oc,5i(greased 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;oh6bs/elae 5 the following speeds, given in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calculate the rmslh;beo 5sa e/6 speed. $v_{rms}$ =    km/s

  The rms speed of moleau*+ k31 xdwm2:idr qscules 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 constant, by wha6 xmeixjtg* 0(t factor d6 jexg0it* mx(oes $v_{rms}$ change?   

Show that the rms speed of molecules in a gapzk rkybq)3ofn 1871 qs 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 sa e* (lnq.wl0n4j3s (fjgh5klyme temperature, the ratio of their rms speeds is equal to the inverse ratio of the square roots of their molecular ma*lhnw ls3qyfe lj 5(g0j(n. k4sses.

  What is the rms speed of nitrogen molecules comd/7d,9pxjvu-k2b p6t :hmnontained 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 mwp,la .q0x3foxygen molecule at 0 $^{\circ} $ C    m/s
(b) determine how many times per second it would move back and forth across a 7.0-m-long room on the average, assuming it made very few collisions with other molecules.    round trips per sec

  What is the average distance between nitrogen molecules cwp,; rg jl e13:tm*l/.mup-,i lzehvat STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular mass j0b(nt2jdgn 7ow we -+8cc by8is 89 u in a living cell 7wcc(0gj8e +o ntw-bj db82ynat 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 1n5l gsg29f1n:ihczd of a gas can be written P = $\frac(1)(3)\rho v^2$ where $\rho$ is the density of the gas and v is the rms speed of the molecules.

  The two isotopes of uranium,w2g90zvima; unn fz28 $^{235}$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 b9 0/5peu e 9q/fhzmkgphases 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 pressxk .a-*mn wgv7a kc*u(ure is 0.01 atm and the temperature is (a) gwac 7-* xna.ukmkv*(90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the hum) x qh*b yb3h3 fy.yb55lk.wtqi1knj ,idity is 50% on a day when the temperature is .,iblb153.nhtyf qkw 3bqy hjx 5*y)k 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a p;3sm(i2 f czvgnh9 qgx+r);h tlace where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular plac( skenl+ i5oecp(cm;s6 ls .l0e in the mountains is 0.72 atm, estimate the temperatus 6smolik((nl0. +ces5p ; lcere at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of water is nzh9cfqjv: 5*530 Pa and the relative humidity is 40%? 9nfcz:*jq v5h$\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the temp-f -/ rzorck0 oadv-8ferature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cooker if the water is boiluq cgstx6-q9 tjd,zm k/30s)ting at a tempera m639k/,z)td uqsq0xsg j-ct tture 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 6v;,q t/6lhx jbtoi3 dvolume 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 m z8qbxj;p2atxu0(b) point of 5 $^{\circ} $ C is drawn into a building where it is heated to 25. What will be the relative humidity at this temperature? Assume constant pressure of 1.0 atm. Take into account the expansion of the air.    %

  Estimate the time needvdstd*63z y v7plzo06ed for a glycine molecule (see Table 13–4) to diffuse a distance of 1t066l oszvv dd*7y3zp5 $\mu m$ 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 k2*-zzzew ic2u6bc5n the surface of insects to the interior through tiny tubes called tracheae. An average tra 6u e2z*2 ni-zb5cwzckchea 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 h/32 cxp eb8 tid6nkg7y.uz+gp as 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 mea. kh 29*exs2c qw4hgvcsure has been calibrated at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A Pyrex measuring cup was calibrated at normal room temperh bu)3 p1u5jjqature. How much error will be made in a recipe calling for 300 mL of cool water, if the water and the cup arebph3jjqu5u 1 ) 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 atm5ku(iqe(1 uh g. After many balloonseq (k ui5h(ug1 have been blown up, the gauge pressure has decreased to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number omo87 qi:0k agtpe9o(pf air molecules in a room of length 6.5 m, width 3.1 m, and height 2.5 m. Assume the tegi7k8 (9teq p0:o oampmperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of mattwp0d g i0( .k:r lmsks8)cz6axer 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 avai;5lvo7 kv uhox.*v 6qhlable vacuum techniques is about6v ;.7qo*5 lvuhkvhxo $10^{-12} N/m^2$ 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 whene8l,s8 ear9ol ypij4 1 10 m below the surface, to what volume e aeo8 isll9pj1,r4y8would his lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moon enters Ea ,oi:ant3+l0 jszbwq7rth’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 reentry.) z,j: 3snbi70w atl+qo    K

  The temperature of an ideal gas is in+ xtw*o-wp -y ja.yok/creased 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 ofi(i8 v tub tz5mw,2il(0sde1e 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 oq2(kgzte /q80uf ip.nhobtg2g;u2*surface of the Earth, estimate the totau0/ b g2tq g*zou.note8;h2pf(gi 2kql number of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules contained in a 7.6bd9 ;x i,6i4whi:d tj7c 5kwqqo2j 7ps$-m^3$ 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 pressuvs e 3 s-sb1g*vrjy1r1re = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, v1 *rsj y3gr bse1sv1-measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a j3swk ah 2g3:ebowl 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 aw v1;t ,gpnbm:t 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 rc64./w :mum4ea h ztkthe 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 onto a glass b,5:4 x9wpqnp yrb3*gf /scjg6ohe) vjar 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, adop7vcf*8, gvnnnmri :a2,da1boted 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, s,apvk y,a:bk sk,-0r y77 nqhhas a pressure 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 Earth is 30+tepgmco t (8yr 6ip.;-bhuebk4b t$ 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 suspenzd oons:l.j);0 t2hao ded against gravity by tennis balls thrown vertically upward at it. How many tennis balls per .o :d) ;alz2ojn0hotssecond 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-d:(xi ep5rcio+ iameter (spherical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the air behaves as a perfect gas. How large is thei+oir( xc:5ep bubble when it reaches the surface?    cm

  Calculate the total waab/0vk;nc3 ; x 0cprlmter vapor pressure in the air on the following two days: k0n;/cpc xrv;3 b 0aml
(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 difference0 *a2an:ctay 3 ncocm5 in the density of iron at STP, and when it is a solid deep in the Earth whea0 3c:n cm*aocyn52t are 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 show that, for an ideal gas at constant press .d;t,jklpnt4 ure, the coefficient of volume expansion is equal toj4t tl,;pk.dn $\beta$ = 1/T where T is the temperature in kelvins. Compare to Table 13–1 for gases at T = 293K (b) Show that the bulk modulus (Section 9–5) for an ideal gas held at constant temperature is B = P where P is the pressure.

  In humid climates, people constantly dehumidify their cellars to prev.,gb udca0hyu,/3t hf ent rot and mildew. If the cellar in a house (kept at 203g,h0udayt./fucbh ,$^{\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