Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the peky+ x* xlsub:*pup+q7: c-x: gsi-tkvriodic table orksl: +*p-g*xpq7+syu:cu x- t bix:kv Appendix B.

Name several properties of materials that ceoi gf8uup*-1 h.g;h/ og+bdkould be exploited to make a thermometer gi/oh-8kbedh1g pg .f+;ou*u .

Which is larger, 1 C 5ibr nnq7n7c/ $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, buy w0kibv* ic(3xg*6b 6om* omtt B is not in thermal equilibrium with system C, what can you say about th bik* gc60 *xm3 *yowvoi(6tmbe temperatures of A, B, and C?

A flat bimetallic strip coo;dqj;j-d ;kba;sxct85: qyk nsists of aluminum riveted to a strip of iron. When heated, the strip will bend. Which metal will be on the outside oa kkx8jtqc:do;;q j;; sy d-5bf 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 coeff z9ket: y6 ci6-pa0zdbicient 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 *w*e7 rkgg,* e 2wsfovof a simple thermostat used to control a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch is a glkgrge efww27*sov,* *ass 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 shape ofozt *+wbz.2 ke a U. Whtk2oz *wze.b +y?

A flat, uniform cylinder of lead f: k e8s/*swgf:a5z kowloats in mercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometer is first placed in a;dnmwy7 ws9v)/ p7au) :efgjo3tylv- hot tub of water, the mercury initially descends a bit and then rises. Ex;l m yw)vfa9/po77tv-)swgj e:nudy3plain.

A glass container may break if one part of it is heated or cl:*8q z ;d++wwjt hfvqhqv6:jooled more rapidly than adjacent parts. Explain. 8vzvh+thqj:*f dw6 l;+qqwj :

The principal virtue oeck3 kuoj9*, ach//hcf Pyrex glass is that its coefficient of linear expansion is much smaller a9,// eho 3kcuk* cjchthan that for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurate at 20 ny3p 8 o;kuuuk/1b:** bhkt fj$^{\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 tvegv;,:s3da vo 1svm (op to bulge so badly the can will not stand vo;d svg a:31(,mvsev up. What has happened?

When a gas is rapidly compressed (say, by pushing down a pi,) yc* jqf9vkmston), its temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperature using the kineti9yvj ,mck*)q fc 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 increase or dui.(uq hlnk s;zs/d+5w+8e yoecroq;su(sh8ku. ld ey+n/5+z iw ease if the temperature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law0euxdf 1qft96v31b2 8ap(y( ra lzkun follows from kinetic theory and the relation between average kinetic energy and the abso90n beu16(1a8ka(t v dxl ufy2fpzq3rlute temperature.

Explain in words how Gay-Lussac’s law follows from kinetizq1g x:fak9 zj7 d2hi3c theory.

As you go higher in the Ear yrcpql4e:j+c- b6d kw ydb,;a4klq:7th’s atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum spk:. r-z3v3 k/ppvg agaeed an object must have to leave the Earth and never return. The escape velocity for the Moon is about one-fifth .p/apk kg3 gvzva:3-rwhat it is for the Earth due to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at room temperature. What dfhij: -cd/xj vnz ,,:g 4xv*ncan you infer about the molecular properties of one relativf/ vhzj,:*x ,icj-xvn:n d4d ge to the other?

Explain why a hot humid day is far more uncomaj thnatj9 d,hh*6a i+/.e j/rfortable than a hot dry day at the same temperatua6jihnt.*h/ ha+tejjrd 9 ,/a re.

Is it possible to boil water at room ba8j-: ;0 tr7-ktw iqg(jhfmltemperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but rgv4kct:muz 0 3s()oqthe humidity is different. Which is more dense, the dry air or the humid ai(4o szmruvt:kcq3g) 0r at the same T? Explain.

Explain why it is dangerous to open the radiator cap of an ovekmhs 3 dn12xgps :(y2lrheated automobile e:k2lmdynx2(s g3h1 spngine.

Why does exhaled air appear as a little whitel)fj hac1(srjvvq+r/ 07+d j e cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram copper pe.6gs0cojcn r( nny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare to the ;0-p ,jtd v9k+qedon;p-jm u ynumber in a silvpp,d+jtv y o;mdq-uk n-90;ej er ring of the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be z kr05b2lt*ck 68°F. What is this on the Celsius scale?bz t05lckk2r*    $^{\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 recd2- nae yr 1w/u3szu2oorded 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 they:lkszggo,g+,9k(hh / y :yw( opi0owrmometer, the alcohol column has length 11.82 cm at 0.0kiylhzswwo( +og y pkh:, (/, 9o0yg:g $^{\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 l9m kla xewzz7/cr4+ 0vong (20 $^{\circ} $ C). How wide should the expansion cracks between the slabs be (at 20 $^{\circ} $ C) to prevent buckling if the range of temperature is -30 $^{\circ} $ C to +50 $^{\circ} $ C?    m

  Super Inva$^{TM}$, an alloy of iron and nickel, is a strong material with a very low coefficient of linear expansion [0.2$ \times10^{ -6}$(C?)$^{-1}$]
A 2.0-m-long tabletop made of this alloy is used for sensitive laser measurements where extremely high tolerances are required. How much will this table expand along its length if the temperature increases 5.0 $^{\circ} $ C? Compare to tabletops made of steel.   $ \times10^{-6 }$ m    $ \times10^{-4 }$ m

  The Eiffel Tower (Fig. 13–29) is built of wrought iron approximate nnz *,-nkr:ih+ x+u8 eab0jhxly 300 m tall. Estimate how much its height changes be0hu *na++-x zrken,:jb8nx hitween 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 th;,c0t blha4 xdat are larger than the rivet hole are often used and the rivet is cooled (usually in dry ice) before it is placed in ;ah ,4tbc0xd lthe 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 water at 4 lq+ itdk -i)0u$^{\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 iz+ uriib8bx tfl47p)o ,/b1l if it is heated from 30 i/i)bb7z u ptf +,8i lrxl1bo4$^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is uo1ojazq-/ y4filled to 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 5;6lr1dl k ziob 2p9 ivov0ew:.b1btm)5.50 mL of water at 20 $^{\circ} $ C completely fills a container to the brim. When the container and the water are heated to 60 $^{\circ} $ C, 0.35 g of water is lost. (a) What is the coefficient of volume expansion of the container?    $ \times10^{-5 }$ /$C^0$(b) What is the most likely material of the container? The density of water at 60°C is 0.98324g/ml.

  (a) A brass plug is to be placed in a ri+3uz ep a ie;wbo71/ncng 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 essp16 tauxx o1x.entially one direction only, show that the effec16 uoxaptx.1x tive coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change cd wm9e tqb.1; tf.-rain the 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 whqg .kgf ;n4v52 o/asg has coefficient of linear expanng2o5 4.qf;g gvs/akh sion $\alpha$ 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 isotro n8q0icc:, v u:ivyr3mpic 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 grandfat/b*occyi d;f-6yo kx0 her clock is made of brass and keeps perfect time at 16o k d/ib0-fx*y;c yoc7 $^{\circ} $ C. How much time is gained or lost in a year if the clock is kept at 25 $^{\circ} $ C? (Assume the frequency dependence on length for a simple pendulum applies.)$\approx$    min(Round to the nearest integer)

  (a) The tube of a mercury thermometer has an inside diameter of 0.17vpkp7p.fd shs l2v 6d72nt t(40 mm. The bulb has a volum l7tpn 2s.7( k7vpv p6shtd2dfe 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 0.41 m is rlph+tp eym1 nz:z4nn.n9 (1pd otating about its axle on frictionless bearh+mez1yp :dn n1tpn4zl.(p9nings 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 much na b 3s4a)(0tf od0nqhstress is required to keep it at thihoa)f (s43tq0 n b0ndas length if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steelan/u*j6(bpfr sb 5x3rwln b;s,,f4ml 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 134.1s+(bm el; baox2cotlq*hz3 q;62nu g+22 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 followinvpce3(t7bb8o0/d3z tg8 ku cyg 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 sot1 c3 yj j9q.w/*kyte1 d7ovqcale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun are aboutd76po4wpqu s fnkk+p 3dg9/6 p 4000$^{\circ} $ C and $ \times10^{6 }$ $^{\circ} $ C respectively.
(a) What are these temperatures in kelvins?    K    $ \times10^{ 6}$K
(b) What percent error is made in each case if a person forgets to change $^{\circ} $ C to K? $\approx$    %(Round to the nearest integer) $\approx$    %(Round to three decimal places)

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

  In an internal combustion engine, air atg lkz6 /.2j:xee* lhwfohs 00u*5swu-txga 3c atmospheric pressure and a temperature of a2 xz *:lw-j3ckhgae /xfsguse00 6.u 5*wlhotbout 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 tgj1iu-tdx -z5he ideal gas law.    kg/$m^3$

  A storage tank conta0q -8mmhwmao 8ins 21.6 kg of 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 contains i f)769,-uuanmpx:m2xtbn i zd;fr3j 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 heliud1x(li 8xl ufy52sqr)m gas is at 10.0$^{\circ} $C and a gauge pressure of 0.350 atm, (a) calculate the volume of the helium gas under these conditions.    $m^3$
(b) Calculate the temperature if the gas is compressed to precisely half the volume at a gauge pressure of 1.00 atm.    $^{\circ} $ C

  What is the pressure inside a 35.0-L l g4ctadt y2uez ap+b7o 3(.z*container holding 105.0 kg of argon gas at 3az4p2b. tg7c*l+tuz doa(ye3 85 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg ofbi+hf 0h.m3i* wsag4m/ewc9t $O_2$ 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 achieve)ty:m tt f;i)v:bqey4s its buoyant lift by heating the air inside the balloon, which makes it less dense than the air outside. Suppose the volume of:t bm4tft;) i y)e:yvq 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 asol g 3fimo*)j4n6.vvt 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 a9s g5 5ie.igvdgw --wmt 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 ypabj;(v/ s jc +av6ft)i4 w)pchild’s hand at sea level and 20.0 $^{\circ} $ C. When it reaches an altitude of 3000 m, where the temperature is 5.0 $^{\circ} $ C and the pressure is only 0.70 atm, how will its volume compare to that at sea level?    times the original volume

  Calculate the number of molecules x. oofmd pm-2xnb95cv--nr d; / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.y.+/w6m e ivtd000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of,46us g,av+c3 svhl9tk:l3)vjklhlq (a) 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 volum b4s/w .mb9qbve 5.1$ \times10^{ -2}m^3$ is filled with air at atmospheric pressure at 20 $^{\circ} $ C. The box is closed and heated to 180 $^{\circ} $ C. What is the net force on each side of the box?    N

  Estimate how many moleculejq rp:i;+9p yrs of air are in each 2.0-L breath you inhale that were also in the last breath Galileo took. [Hint: Assume the atmosphe piy+9:p;r jrqre is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translationa/b ltx z)anw (r5ewae *a7md8;l kinetic energy of an oxygen molecule at STP?na;x 7wbe *d(azlr5 /8w tea)m    $ \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 6idqre p7:9 i28itsba at a temperature of about 60009ir dq6 2a7i 8tsbi:pe K.    m/s

  By what factor will the r8+0ym: 7w;lm ivkn bczms speed of gas molecules increase if the temperature is increased from m +zbi 8nlvwy m07:ck;0 $^{\circ} $ C to 100 $^{\circ} $ C?   

  A gas is at 20 $^{\circ} $ C. To what temperature must it be raised to double the rms speed of its molecules?    $^{\circ} $ C

  Twelve molecules have the following speeds, given in units of km/s: 6, m e hho;i5 v4go7mlk9y+*ma w/2, 4, 6, 9;ah+m o5gm7/o* lmkwy v4ehi 0, 4, 1, 8, 5, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas atid y(3nac2 , wj9ae koe:pwf:: 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 constan+dg;nojjg9o 2t, by what factor does +;ogd9 jjn2og$v_{rms}$ change?   

Show that the rms speed oj+ks2cdnhq6l6 )n ;paf molecules 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, the ratio of theirrqnd bme (929gw81top rms speeds is etoq1w g8b rp(29de9mn qual to the inverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen molecules containeni 0f95evfm tuiqmmsp3n i vu r,i795p(8x6)pd 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 8d 3q9ok2bbbfdi4 lwrwe/ 84kan oxygen molecule at 0 $^{\circ} $ C    m/s
(b) determine how many times per second it would move back and forth across a 7.0-m-long room on the average, assuming it made very few collisions with other molecules.    round trips per sec

  What is the average distance between nr(ct 66binwyte9 w:93b vrb-aitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molo)qi nk-xk/nd z(5/3 q /weikpecular mass is 89 u in a living cei/k/)podin q/nk-e3k5zxw ( qll 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 w3 zr 42z tztdvt :zyo1rq9y (ell-l,y0ritten 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 urani 8p (j,7b 6b:scjrpfkqum, $^{235}$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,pq,*fu1jvvr*d v u 7s can $CO_2$ exist? (b) For what range of pressures and temperatures can $CO_2$ be a liquid? Refer to Fig. 13–21.

Water is in which phase when the pressure is 0.01 atm and the temperature ish h* j53e gse8mn.i,dy (a) 90,h5 8gsd3.nhi*yemej $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (awen q+y-xm6zdy8.2qhcb x a.)exp6*z pproximately) if the humidity is 50% on a day when the tempd qamq6.bx h+zy -*ezwxnecyx p6 )2.8erature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a placecrnc+x18nru(:- cr6 h mhm) zj where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is 0.72 atmu(a9chngg/ oe -19jas zd wc0), estimate thaawd1c /h9onzeujsg9 gc-0 ()e temperature at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of water is 530 Pa 7wgfjt1o w,0lkc 9k 6oand the relative humidl t c1fkwwoj9o0k6g, 7ity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the tempge1 )2rqurhbf/9xq2 nerature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a w (u57fqw,f3or ,gd/vyk0y g*va p/yrpressure cooker if the water is boiling at a temperature of 120 vw7wfryruf(gdyo5 q/v,/0y a,3 pk*g$^{\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 6q+ 2xq4sb:zdrq*uv9f5hw 8 e:eh7sts80$m^3$ at 25 $^{\circ} $ C is 80%, what mass of water can still evaporate from an open pan?    kg

  Air that is at its dew pointl8u2+ tyl4cn m 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 glyiq03rxu 5xaf+c 1cz(gf k0r7pcine molecule (see Table 13–4) to diffuse a dista+pf 0z xxkr(ciq5a0f1c7gru3nce of 15 $\mu m$ in water at 20$^{\circ} $ C if its concentration varies over that distance from 1 mol/$m^3$ to 0.4 mol/$m^3$ Compare this “speed” to its rms (thermal) speed. The molecular mass of glycine is about 75 u. t $\approx$    s ([color=rgba(0, 0, 0, 0.85)]Round to one decimal places) $v_{diffuse}$    $ \times10^{ -5}$ m/s
$v_{rms}$    m/s

  Oxygen diffuses from the surface o4 ute ac3d i*yr2z-mlfo*5:xq f insects to the interior through tiny tubes called tracheae. An average trachea*4qemxrdal t2 uf:-*ozi3c y5 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 has been calf krvr/x9wpr1f- h b5.uhk.6eibrated 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 meas qkj7/feq1p r j8y+dz 800tpo2h.sq leure 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 te8omec4 5 bn3av2 xzz*xmperature. How much error will be made in a recipe calling for 300 mL of cool water, if th423c* bvxoe5z nz m8axe water and the cup are hot, at 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in a helium gas cylinder is5ux5lbmj 6y8r initially 28 atm. After many balloons have 5 rjm6xlu85yb been blown up, the gauge pressure has decreased to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air molecules in a room of length 6.5 m, widtz9eux dr9: s(e hmq.q 5tg(k1jh 3.1 m, and height 2.5 m. Assume the temperauh9r(ed:9 zse.jxq k(g mqt51ture is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is about up48 jzm jg7:gone atom per $cm^3$ mainly hydrogen atoms, and the temperature is about 2.7 K. Calculate the rms speed of these hydrogen atoms, and the pressure (in atmospheres).$v_{rms}$ =    m/s    $ \times10^{-22 }$ atm

  The lowest pressure attainable using the best available vs* )8vyhwj0 /uxml ,9im+tmyy acuum techniques is abous y+m yh*mm8vwltxj/0y u,)9it $10^{-12} N/m^2$ 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 belonxx7nh(qyd v*+r8d v(ci6.jjggl 6a2 w the suvnnx rj 2y(+aid 7. gq6jl( hv6g8cxd*rface, to what volume would his lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returns3 3q3/ ufvrosing from 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 special mater q3s/sr33 fovuials; indeed, part of it does vaporize, and this is seen as a bright blaze upon reentry.)    K

  The temperature of an ideal gas is incrl3w: l3vj x8rfh.irv1 eased 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+in-km .il3bm 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 value of atmospheric pressure at the surface o9a1,n8a.w 1 jo ojmuu*cr fc1q;wxy: wf the Earth, estimate t1ma:c .qwyuj wua1 , nc*ofjw;rox 198he total number of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen mo cae+u,9,wi k0pagju5lecules 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 inc(3(p bj 5zqvuqvtbj4r6+ au4 a hospital has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder la64 qjba(v5 qc4v(+tzrb up3j ust if the flow rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of tti1 qh88bp-y 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 gasolin rd4r.*j:x r j;rge*yre at 0$^{\circ} $C is 0.68$ \times10^{3 }kg/m^3$ What is the density on a hot day, when the temperature is 38$^{\circ} $C?    kg/$m^3$
What is the percentage change?    %

  If a steel band were to fit snugly around m2vu .gz if4xc858mw hthe 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 tgda/,jcx 9l )*yinosog*c 6ak:bg5;t ightly 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 standardcju*.ctb,s f+/i p4qzor29eog*q* g b, adopted 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 ful udpmt tvl;zea 7t; c/k)-;.dfly charged, has 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 i ,veu6ms)um0kgh4:-9ueo y sg s $ 1.12\times10^{4 } m/s$ so a gas molecule travelling away from Earth near the outer boundary of the Earth’s atmosphere would, at this speed, be able to escape from the Earth’s gravitational field. At what temperature is the average speed of
(a) oxygen molecules,    $ \times10^{5 }$K
(b) helium atoms equal to $ 1.12\times10^{4 } m/s$    $ \times10^{4}$K
(c) Can you see why our atmosphere contains oxygen but not helium?

  A 1.0-kg trash-can lid is suspended against gravity by tennis balls thrown vertl uq pkyz/:*o4wp 0mr2ically upward at it. How many tennis balls per s*ku2/wppz lmq4r: 0yoecond 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 j45ik +.uwkdz of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the air wuzki + .5dj4kbehaves as a perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressu)ptuh* rddh i-dxw.;6.lpbjc2osz 07 re in the air on the following two days: zod7h6-02 sbl d)ju*hr.xd;p pctw. i
(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, and when it ih8c:+1l huhmvs a solid deep in the Earth where the temperature is+h vlc: uhhm81 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 preg 1(g/ey1qgt kw8ct eip9g*k ;jl1ri3 ssure, the coefficient of volume ; tjgwkpi9lkee8 tg/1c*ygqi1g(3 r1 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 cellars to prevent2( nfs6 w th0hx,xn jhoi)n55ka pai1; rot and milde)w 6hs05ofh2,nnxjtak p;5nhi1 iax(w. If the cellar 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