Which has more atoms: 1 kg of iron 5:/fz 4v:koo8 ibxqoi or 1 kg of aluminum? See the periodic table or Appx :5zfo/kvi4:8o oqib endix B.

Name several properties of materials that could be exploited to make a jrnve11oe w d,bk+0e9thermometbe0 j 1nrk1+ ow,ee9dver.

Which is larger, 1 Cxztnyl4 g24j) tq .xo, $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with systh abc8gm i/hk15)9w4 tfke*grem B, but B is not in thermal equilibrium with system C, what can you say t kw1 mcegkh9* )ihr4g5a/bf8about the temperatures of A, B, and C?

A flat bimetallic strip consists o o+ n4tj)q+k3uwoy gy)f aluminum riveted to a strip of iron. When heated, the strip will bend. Which mett yo qg+u4j)oy+nw )k3al 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 coefficy5+uy nu;x.e9 um mb)d xhv9(qient 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 thermostat used to control a fu7b a8h*sx4* cbgf 7jgnrnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bof 4g7cnxashg7*8b* jbnded 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 section in the sh k1j)yt(:hilfm+l gj 5ape of a Ufy l5g+kli :jmht) j1(. Why?

A flat, uniform cylinder of lead floats in mercury at ob4t cj(kg8 -26t0hncn laq g80 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-gla gk:rmm5i4lfqvr -4j-l d 5jl vzi;2n,ss thermometer is first placed in a hot tub of water, the me4 l vlv-imn-r,kjrfgj;d lm4i5z:q25rcury initially descends a bit and then rises. Explain.

A glass container may break if one part of it is heatedt12mes j5ygih epy*81 4i7ejz or cooled more rapidly than adjacent part7ye5e2is4j yht 8ep* 1z g1mijs. Explain.

The principal virtue of Pyrex glass is that its-c2j m uq/ftuyi,h./i coefficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this givesi2ju /,cq.yf /tmiuh- rise to the increased heat resistance of Pyrex.

Will a grandfather clockb9qn8 b nof0e8, accurate at 20 $^{\circ} $ C, run fast or slow on a hot day (30 $^{\circ} $ C)? Explain. The clock uses a pendulum supported on a long, thin brass rod.

Freezing a can of soda will cause its bottom and toq;7 5jcps:vaa-r1ckpp to bulge so badly the can will not stans57rqpp-aj:k c;1av cd up. What has happened?

When a gas is rapidly comprnp 9p 0* h ywtfyo0f1hk/vz3b;essed (say, by pushing down a piston), its temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperature using the kinetic theory, in pt/ 0zfh *n vby o3pp;h9y01wkfarticular 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 increase orv, j8zx/vtoxz**-ld7 jl b*pnjjp - k, decrease if the temperature is ij*-l*z/d-* tl j,x7jkn8j p,z xvpbovncreased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’i.i6gt+q /5bn.h a, f/v gcubvs law follows from kinetic theory and the relation between average kinetic energy anubq/,5 fvi /ghg +6vtacn.i.bd the absolute temperature.

Explain in words how Gay-Lussac’s law follows from kinetic th3he ,zjb w9r; 5ah(glyeory.

As you go higher in the Earth’s atmosphere, the f1u(sji 09:w eyjy,hjratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speedalc 0hj ldqf-k*28j;n 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 hashc;fk8 j02jqla d nl-* practically no atmosphere.

Alcohol evaporates more quickly than wp 6ty c2cbmv-/6eof h8l -wcmzb.*1 pwater at room temperature. What can you infer about the molecular zp -wb*y8pchlmwfo/t -c12 vm.b6c e6properties of one relative to the other?

Explain why a hot humid day is far mon pfsx4b4hg5 . .hbn(bre uncomfortable than a hot dry day at the same temperaturenb.sn 54xbfpbhh 4g. (.

Is it possible to boil water at room temperatu7; tnti x;dkd1re (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when t hj5v4,jxtp2x+yr iog j+ql45he air temperature is the same but the humidity is different. Which is more dense, the dry air or the humid air at gjt4 v5+ ,4xhpj+jlx5oyi2qrthe same T? Explain.

Explain why it is dangerous to oppg74e9j jm.hn en the radiator cap of an overheated automobile 9e4mnj.7gphj engine.

Why does exhaled air appear as a little toen1(up*2f3hdj 6nlgq rdg b /v,af l,6j0i9white cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram copper pennfnz8w cl6 z8v.6f h- 3pahmo2/fnyvr0y?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compa4zb h*zah8 g0n:;tyhuyg ji. :re to the number in a silver ring of the sam:yauhh gnh*4tj. z8b: z0;ygie mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often ( rg7kra.zk7it2 nns6taken to be 68°F. What is this on the Celsius scale? z7ksnnr7 2ti(a. g6kr   $^{\circ} $ C
(b) The temperature of the filament in a lightbulb is about 1800 $^{\circ} $ C. What is this on the Fahrenheit scale?    $^{\circ} $ F

  Among the highest and lowest temperatures recorded are 136g/ m7l f )/+gl2ebhctd $^{\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 9mg*crndd3:df . du0:bl ca- ghas length 11.82 cm at 0.0 0: gngmddrafld-c u*d .:9b3c$^{\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 long (20e 7njkftl,zjn) ke)ggj; y ibr4 8,0p5 $^{\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. 1(jixyeq5as lv-;b e.: 3–29) is built of wrought iron approximately 300 m tall. Estimate how much its height changes between July (average temperature of 2se 5 y.v(:jeibxa-lq ;5°C) and January (average temperature of 2 $^{\circ} $ C). Ignore the angles of the iron beams, and treat the tower as a vertical beam.    m

  To make a secure fit, rivets that are larger than the rivet hole are often pw7v9s9ynun xv y8w(b 5fd;mz1 (hg4pused and8 (9z vnb(p gy9hxfd5su4m;v pwywn71 the rivet is cooled (usually in dry ice) before it is placed in the hole. A steel rivet 1.871 cm in diameter is to be placed in a hole 1.869 cm in 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 waterh*ru;;1qhy g4+a fb, gxnktrx3rkm e7/ pg8a7 at 4 $^{\circ} $ C is $ 1\times10^{3 }kg/m^3$ What is water’s density at 94 $^{\circ} $ C?    kg/$m^3$

  A quartz sphere is 8.75 cm in diameter. What will be t48vxa x6iyq*ue :ex/o88w2zi bzwz 9its change in volume if it is heated from 30x 86i8 xyatx/2eoez*u b4qwz w9iv8:z $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350.0 mL of wat;h-l7kho0t vfwr 0wp, er 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 my4 0m6ddibln,L 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 t63y,sj2pd bsn0 ikbubu9b36/es pejz0 90rh do be placed 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 expand in essexng- e2cosa ;//gn/b rntially one direction only, show that the effective coef/n cbe-ga ;/nx ro2gs/ficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in thgnsjx: s:k14 zi+lh y6e 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 width w has l5 2o.ga ;:n9b ss9lb;piriwf coefficient of linear expanssp o 9s9g;.rwb;lailbn2f :5iion $\alpha$ 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 k2 6gxnxdvtzq9 n( 4s*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 grandfa9kea-+eh 2 w oin9fy+mther clock is made of brass and keeps perfect time at 17 ma-92 k+efhenyiwo9+$^{\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 diamet3t*3xb9mf o l6cri dn,m sc7w3er of 0.140 mm. The bulb has a vcx ot,ws73c9n*md b m3l63r fiolume 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 radius 0oioi rn7/o 6m*r*dq*p.41 m is rotating about its axle on frictionless bearingdpmqoo/ri i7 **rno6*s 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 length when at 15°C. How mucyxk/ol- q w*r2dxg8(xh stress is required to keep it at this length if the temp*2qygx k(o w- 8drxxl/erature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam ofp7:1mskst n-s 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 13lvz4f+zhieb*sl:- t+)ylu0 c 4.122 cm at 20$^{\circ} $ C is to be enclosed by an iron band. The circular band has an inside diameter of 134.110 cm at 20$^{\circ} $ C. It is 7.4 cm wide and 0.65 cm thick.
(a) To what temperature must the band be heated so that it will fit over the barrel? $\approx$   $^{\circ} $ C(Round to the nearest integer)
(b) What will be the tension in the band when it cools to 20$^{\circ} $ C?    N

  What are the following temperatures on the Kelvin scale: 7;yhyjh3k7ik- n*0vgg:hhce
(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 th 0hb 3f048ev sdc:pfmxe Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the int2dqwdmn javqy4p qx2kn-6 0+2erior 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 enginmp 4f;d*mjpo j+rj+u)e, air at atmospheric pressure and a temperature o4+ muj)rjf;d ppm jo+*f about 20$^{\circ} $C is compressed in the cylinder by a piston to $\frac{1}{9}$ of its original volume (compression ratio = 9.0). Estimate the temperature of the compressed air, assuming the pressure reaches 40 atm.    $^{\circ} $ C

  Calculate the density of oxygen at STP using the ideal gasgx3zli44 0ikof ;np(q law.    kg/$m^3$

  A storage tank contains 21.6 kg of nitrbl23w blc b8+wn u(xr(ogen ($N_2$) 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 dte-vjnci+h( l-s 1w9v*iy ) o18.5 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 ) 2fk-i;vald-0oqnnsiu 0e0, h zi+ha gas is at 10.0$^{\circ} $C and a gauge pressure of 0.350 atm, (a) calculate the volume of the helium gas under these conditions.    $m^3$
(b) Calculate the temperature if the gas is compressed to precisely half the volume at a gauge pressure of 1.00 atm.    $^{\circ} $ C

  What is the pressure inside a 35.0-L container holding 105.0 kg of argon ga7il1a- fch sl:s at 37illhc1 a-sf:85 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 k vs l5)4hzmc) g s;qbo/3r:nkwg 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 inside the ballood0 f(i)ng.t+5yw knv on, which makes it less dense than the air outside. Suppose the volume fi o)gy5wt .+nvk0(n dof 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 uexgo;+/i0ytns 2socop;0; g 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 18.ay 0o zp66n+pamz.l.d 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 zn tewy*gk(l4vicw/ijj/+ u et 81;f lgt*e;/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 ysf5 ock a9e/3molecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are ther0yjh8mdo/agb*2 .i l le in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) moles nh7nzlkc7/rt7 e cn*;,    $ \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.:1fdz .1d1xp x.gnpqx1$ \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 inhalw)48htpcls3m zvc 2x0 e that were alh8cp 32s v40xc t)zlmwso in the last breath Galileo took. [Hint: Assume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average trans9aihln xna-.3lational kinetic energy of an oxygen molecule at ST.ana9i3hx-nl P?    $ \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 a tempera :ucf3:v(:lnz l843jonta;xy5 :a qpoll qpp +ture of vtn 5p ll:afz ::ax; n:cpj3qol(o q8y3u4+plabout 6000 K.    m/s

  By what factor will the rms speed of gas molecules increase if the tudif8lx)stt68 c*em 7emperature is increased from 0*7tem )dlc8fi s8tx6u $^{\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, :cqqjl:0 7mmc eqof-. 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calculate thec.m7: comq qjl:0qfe - rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in 82bx uov5oz d;jcr+)la 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, bz 2wozl6i 4ly+t.k*eqy what facwl.e62o z 4i*+y ktqzltor does $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is given b .od p)ea, -hy9s6ug)7d*e ezaruexb 5y $v_{rms}$ = $\sqrt{3P\\rho}$ where P is the pressure in the gas, and $\rho$ is the gas density.

Show that for a mixture of two gases at tcmgpfm+p jw m .q;z;2t o5v5t1he same temperature, the ratio of their rms .mg v5tt;5+cpp fj; qmzm 21wospeeds is equal to the inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen molecules contain:)hebk(mw-y qs.9e9 mkq 8ooped in an 8.5$-m^3$ volume at 2.1 atm if the total amount of nitrogen is 1300 mol?    m/s

  Calculate (a) the rms speed of an oxygen molecule at 0 5*mh- d;m+s:+ool jhmlct zy+$^{\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 moleculesuc v4j-,;iu :fjl;cpu at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of1cl: qa jdx9 9d6uxx3r an amino acid whose molecular mass is 89 u in a living cel 3r cuql16j:x xad99xdl 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 bekzl4d3.r/ oz xn kcc08 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 urzku1yekym0 (:n+ .bbsanium, $^{235}$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,--vgr01 b h: 4e *m+yny.l9rbq wqj7 tonxgrz4 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 pressvb:(kj6 hyceg. .h3w n x:*lbuure is 0.01 atm and the temperature is (a) 90 jce6h :bkhu(:n* .3b.g yx lvw$^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if thcn*a6bs1as8h e humidity is 50% on a day when the temperature is n a6bs s8hca1*25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressunzln g. f-*+tlov)e(c re at 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, es;s 73cbvj vqe1timate the tem b;3v7sj ve1cqperature at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure n y+t ojm:qh5z6 f6-sqvtc,z8 of water is 530 Pa and the relative humidity is 4:oth6ny m5 jqzv6-tq,8+s cfz 0%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on axa4(2 ,*yh6 qlw styo q7oqd 9;j0toua day when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a preine2 6 1dndbl+ssure cooker if the water is boiling at a tempdb1 2den+6lin erature of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room of volume 688)c ugr6y1sss 0$m^3$ at 25 $^{\circ} $ C is 80%, what mass of water can still evaporate from an open pan?    kg

  Air that is at its dew poie6;g n lw7aht1nt of 5 $^{\circ} $ C is drawn into a building where it is heated to 25. What will be the relative humidity at this temperature? Assume constant pressure of 1.0 atm. Take into account the expansion of the air.    %

  Estimate the time needed for a glycine molecule (see Table q76jlp x -u6fz13–4) to diffuse a distancjl6 x7 -f6qzupe of 15 $\mu m$ in water at 20$^{\circ} $ C if its concentration varies over that distance from 1 mol/$m^3$ to 0.4 mol/$m^3$ Compare this “speed” to its rms (thermal) speed. The molecular mass of glycine is about 75 u. t $\approx$    s ([color=rgba(0, 0, 0, 0.85)]Round to one decimal places) $v_{diffuse}$    $ \times10^{ -5}$ m/s
$v_{rms}$    m/s

  Oxygen diffuses from the surfyublm*s:/ ug* ace of insects to the interior through tiny tubes called tracheae. An average trachea is about 2 mm long and has crol g**/ my:suubss-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 has been cap)m)4y t /geeolibrated 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 calibrated aliq9 o3* u4ze9p6 klezt 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 wabq5mu rl kj.uz.4a 0v2s calibrated at normal room temperature. How much error will be made in a recipe cal5j 2uk0r 4 au..mzqbvlling for 300 mL of cool water, if the water and the cup are hot, at 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in a helium gas cygkuae2*q1ii2 linder is initially 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm 2u2*akig1ieq. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air molecules in a room of leng .m zi,nexs,x*th 6.5 m, width 3.1 m, and height 2.5 m. Assume the temperature is 22snmxx,*,ezi . $^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the d6glo2x+l fip+(e/ pr uensity of matter is about one atom per $cm^3$ mainly hydrogen atoms, and the temperature is about 2.7 K. Calculate the rms speed of these hydrogen atoms, and the pressure (in atmospheres).$v_{rms}$ =    m/s    $ \times10^{-22 }$ atm

  The lowest pressure attainaai; 0i 7x)uq hlwy k;fq+,ru+mble using the best available vacuum techniques is about rxh)ima;q++fuqyl u; 0ki 7w ,$10^{-12} N/m^2$ 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 his1 /bxd:oskm5m lungs to full capacity of 5.5 L when 10 m below the surface, to what volume would his lungs expand if he quickly rose to the surface? Is thim:xm1 5/dbosks advisable?    L

  A space vehicle returning0*r5 yytnfh :8e5; fwn+kejjw from the Moon enters Earth’s atmosphere at a speed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vf nj;ef+htjkyw : rny5*0 85ewehicle with this speed correspond to what temperature? (Because of this high temperature, the nose of a space vehicle must be made of special materials; indeed, part of it does vaporize, and this is seen as a bright blaze upon reentry.)    K

  The temperature of an ideal gaz,9gp z c,xhf(cp ta g:b8wy;9s 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:,+9u -y orj0iwc mlhn of 770m$^2$ (a) What is the total mass of air inside the house at 20$^{\circ} $C?    kg
(b) If the temperature drops to -10$^{\circ} $C what mass of air enters or leaves the house?    kg

  From the known valueleam5o6- -,w4z h*kpzz tt*oj zs7oe ; of atmospheric pressure at the surface of the Earth, estimate the total number of a4a,t7eo ksj lp-o zo zzw zm6*;th-e*5ir molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules /)kta 0ys6fv mb5/a gkcontained 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 ez5t1:i xsannqj lj cc;5p929gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder lasnpsa2c x5jtn1cl: 9e; 95jizqt if the flow rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats bb(*chd(/h k1smm;f ut( gum4in a 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 0q. jt luhefo8-w2.ctq ;6 -mpt$^{\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 arouehb/),a l) 8h9r5e uh-1 lx;,r2y ogzzrlhfn xnd 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 tightl jg;cd0.y mqy s::f zvq5qg.d0y 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 bqx)z qr2 wt m (ut1itg5 9s9etln8.5dthe 18$^{th}$ century, was a platinum bar with two very fine marks separated by what was defined to be exactly 1 m. If this standard bar was to be accurate to within $\pm1.0 \mu m$ how carefully would the trustees have needed to control the temperature? The coefficient of linear expansion for platinum is $ 9\times10^{ -6}C/^{-1}$. $\pm$ =    C$^{\circ} $

  A scuba tank, when fully charged, has a pressure of 195 at3 z)f .qvtkt-t:ih lwz 2lcw72m 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 -g64shoro, b/bde2q,r/n ujx zp 4y0r is $ 1.12\times10^{4 } m/s$ so a gas molecule travelling away from Earth near the outer boundary of the Earth’s atmosphere would, at this speed, be able to escape from the Earth’s gravitational field. At what temperature is the average speed of
(a) oxygen molecules,    $ \times10^{5 }$K
(b) helium atoms equal to $ 1.12\times10^{4 } m/s$    $ \times10^{4}$K
(c) Can you see why our atmosphere contains oxygen but not helium?

  A 1.0-kg trash-can lid is suspended against gravity by t;j70fobnw(cwo ( wt*qennis balls thrown vertically upward at it. 70nwbwo; o*qwf jc (t(How many tennis balls per second must rebound from the lid elastically, assuming they have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter (spherical) bubble ww;tv78b.qbg 3z)sgg 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 the bubble when it reaches the surface? z;v83st)bbw wq 7gg .g   cm

  Calculate the total water vapor pressure in the air on the following twvo g: (i-chwtwo t,*:wo days: , tciv:wwh:t-*o og(w
(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 STP, a+u;uw-,v f* jvox w1ab wxro:4nd when it is a solid dea;v:- vxxw*w,ob14 + oruwufjep in the Earth where the temperature is 2000$^{\circ} $C and under 5000 atm of pressure. Assume the bulk modulus (90$\times 10^9N/m^2$) and the coefficient of volume expansion do not vary with temperature and are the same as at STP.    %  ----待选择----decreaseincrease 

(a) Use the ideal gas law to show that, for an ideal gqm q 3sovk2a:3/nj1 pvc qn-:sas at constant pressure, the coefficient of volume expansion :njqpsv vs2mq:anq o33-c 1k/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 dehumec z/o *ly*b0syf 77lfidify their cellars to prevent rot and mildew. If the cellaryl*sf*ez cof7/b y0 l7 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