Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodic ,kz k5,.n.z-c hjluos table ok.,.kcuz ,nhj-s5 lo zr Appendix B.

Name several properties of materials that vkwpjpc .w-5q 4b+gc 3could be exploited to make a thermometer.jpw .p kcb-q3cg v4+5w

Which is larger, 1 Cr*sbce 3o(w8l+ oe)5py 8w ygh $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, bum6 dv: ;7 xd)eosk9t9-7ibjiq+ tsfrj t B is not in thermal equilibrium wiik9oe6sj9dxs7ftv; ij t) + -:qrmd 7bth system C, what can you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to a strip of iro mup, 7v /megidr0p;9zn. When heated, the strip will bend. Which metal will be on the outside of the curve? [Hint: Su,9; v7epdzg ri/mm p0ee Table 13–1.] Why?

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

The units for the coefficient of linear expansiony0 l+1 re5jxooa13a zh $\alpha$ 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 controq1 4hk5ryy 1kel 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 conduct ker51ykyh1q4 s 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 a)kaoi24cs:; pgp pjz;(a :g stt the ends often have a section in the shape of a U. Whg(ks4o tzcg jipaa;p: 2 );s:py?

A flat, uniform cylinder of leadyo+ xqnkb+ 39z floats in mercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometer is first placed in a hot tu*w+ c.efc - ce;k s6:tebx.rm;vjz r(qb of water, the mercury initially descends a bit ae* sxqetmzr ;(:- vr.jf +. ccbkwe6;cnd then rises. Explain.

A glass container may break if one part of it is heated or cooled more rapidlyc3e9 *kxl3ry9zklceq,3zv)htz x ,c( than adjacecxx hz,l3 3c*c( yl93zr9t z vkkeq)e,nt parts. Explain.

The principal virtue of Pyrex glass is that its coefficient of linear expansion i t) v/v h+)00to9 oijul*lcycis much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to tht )/ j+ilovuht9lov )i00*ccye increased heat resistance of Pyrex.

Will a grandfather clock, accurate a/ j.0 y:mrqq/acxf.qk t 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 i:mkn52labbc j-u2h e: ts bottom and top to bulge so badly the can will not stanj h:-2uelb ank2cm:5b d up. What has happened?

When a gas is rapidly compressed (say, by pushing down1pn wv3p/7mttwa0ku :ik) r+g a piston), its temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperature using the kin:m3t+t7n1gr v w /kwpi)ua0pketic 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 increa i1 jz8answ; -g;t9ymbse or decrease if the tempea9y 1 -b8n;zgwm sjit;rature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s l6yfyou5r 79 dlaw follows from kinetic theory and the relation between average kinetic energy and the absolu5y679yorfd l ute temperature.

Explain in words how3/ dyeho9/tz ag-dit*p 10t cc Gay-Lussac’s law follows from kinetic theory.

As you go higher in the Eartex2-( xf xpxe6h’s atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for th5g 5gy9vi9;uvk h zxe:e Earth refers to the minimum speed an object must have to leave the Earth and never return. The escape velocity for the Moon is about one-fifth what it is for the Earth due to the Moon’s smaller mass. Explain why the Moon has practicax9k;g ivhz95:gevy u5lly no atmosphere.

Alcohol evaporates more quickly than water at room temperature. Whntu (djq.-b+wumt,5 sat can you infer aboum . dqt,(sub ut5-wn+jt the molecular properties of one relative to the other?

Explain why a hot humid day is far more uncomfortmtpd/fsk x0sk .*z*5vable than a hot dry day at the samep *.fktvd/*szm5 0sxk temperature.

Is it possible to boil water at room temperature ()0w3r q4 teg)qrytxb 320 $^{\circ} $ C) without heating it? Explain.

Consider two days when thetdk,z:gyspxj/;: 8 iu air temperature is the same but the humidity is different. Which is more dense, the dry air or the humid air at the same ,: :gky/z;psxudijt 8 T? Explain.

Explain why it is dangerous to open t8z i p0 ,jqtw9-;rssao3kr uq+he radiator cap of an overheated automobile enginatu,z8ipwoq3+ ;sj qs 0 krr9-e.

Why does exhaled air appear as a little white cloud in the w;giyk/ -xc9t) bx t-dzv)-pjpinter (Fig. 13–28)?

  How many atoms are there in a 3.4-+tn81nc )zfcn6ri )p jgram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare to asp +8/thl t/nrq8 lvq4: dzuux8yc7, the number in a silver ring of the samehz q7dtrl 8unclu,vtq:+ 4y8/s/p ax8 mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often tfs rdmb4.nzh9pgk,(3n,a h(q aken to be 68°F. What is this on the Celsius scale? nb,n.( qgk shpmzf(94 ,dar3h   $^{\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 8tsud.w/ oxl5j k43iprecorded 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 ai 8w:n(sskb /re8xf5 glcohol column has length 11.82 cm at 0.88(bw5s sg:n x/rife k0 $^{\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 sr )-ptv0(ylns:ov5p 7rvt-(xj n dv+x labs 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) irtrkp2kz4 +)as built of wrought iron approximately 300 m tall. Estimate how much p2rrt ka zk+)4its 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 that are larger ltnxsa 2(y2r/ nz63 qxthan the rivet hole are often used and al2n3x zys 62/(xqrtnthe 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 water dajtuf.wy,7 ayg ,av; s4p/2y 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. xxl geg1 )l,x2nchj/ l-7(hh sqa4*cj What will be its change in volume if it is heated frc7xj, j*x4qe l(cg xhh-sh 1n/gl2 al)om 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim witdbigbinqg cpqq x6 198+m33m,h 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 sjpp6hk y,./h/evuvlb;e)1 o.:xsuy 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 d40.xdvp 3uxfpw - ho5j8fmd(to 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 i mt, o;-vsqf8cn a long, narrow vessel so it can expand in essentially one direction only, smt8v -qsf,c;o how that the effective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in thva /:oh.q71q dg6piy me 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 coefficient of linear ejrwk* qrjwa 7n;w5 4wt((4lfkxpansion ww(;wa(f jw5j*4kkn7 r4qr lt $\alpha$ 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 s, 3 womc tsozh:+ iqe*uw,0,c8vjwii m8;td,yolid, $\beta$ = 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 keeevn .w42l fp3q7rqia5ps perfect time at 174pqr ei lna75 qvw3f2. $^{\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 d6w(g;ox um;u ,pya(pp l)wq0of 0.140 mm. The bulb has a volu a p,qy(0lo;; 6d)gw mxupwu(pme 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 0.4wz -- .)hs)j .pvk*xdk7gaaup1 m is rotating about its axle on frictionlej kv7 hapgdx kp.-) aw)zus.-*ss bearings with angular velocity $\omega$ = 32.8 rad/s If its temperature is now raised from 20.0 $^{\circ} $ C to 75.0 $^{\circ} $ C, what is the fractional change in $\omega$?   

  An aluminum bar has the desired length when at 15°C. How muckk) rj*,ec wa 5rutn30h stress is required to keep it at this length if the temperature inc r 5a*k3,jk0u erwnt)creases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-sectional area 0.0n zt0g)dq(6 bu41$m^2$ 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 j8 umzn rg48(:(sw gai134.122 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 followings /5nbq/ aq z-lycz+0u 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 Ffx*;tfss2s-oh2dce 8 s*v ssfb4gd25 ahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Eaawrlg8 n8c)3orth and Sun are about 4000$^{\circ} $ C and $ \times10^{6 }$ $^{\circ} $ C respectively.
(a) What are these temperatures in kelvins?    K    $ \times10^{ 6}$K
(b) What percent error is made in each case if a person forgets to change $^{\circ} $ C to K? $\approx$    %(Round to the nearest integer) $\approx$    %(Round to three decimal places)

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

  In an internal combustion engine, air at atmospheric pressure and a temperamx.t/gne y h49ture of aboh4ymgxte.9 /n ut 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 Sjib 8uzwpsn8 z-o9i:us33 uq +TP using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 7x6z;b 5wmg+cvxcfq* 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 bcr.jq5 xnf7yoa4x :q .,o/fnj p94bkcontains 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 ir7.s xrpz 4) wk (0y+prl:gggss 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:tqvr-.dy:l q-L container holding 105.0 kg of argon gas at 385 Kvqdy -q .t:lr:?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg of qvn od,y38tm;+4wtkv.qgys jk;0ir + $O_2$ 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 li7yx5n5qu.9w xn am gh qsqy*s; f.-0iqft by heating the air inside the balloon, which makes it less dense than the air outside. Suppose the volume of a ball0q;7un5q.*sshwnxm yyigxq-. 59fqa oon 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 a mb . xr8t;eror-y-jvld(ik0; t 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 18.0 rbzr.y::wfq/ 4f+ik3kw 7h gw$^{\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 ec5age-v; c0 fwscapes a child’s hand at sea level and 20.0 $^{\circ} $ C. When it reaches an altitude of 3000 m, where the temperature is 5.0 $^{\circ} $ C and the pressure is only 0.70 atm, how will its volume compare to that at sea level?    times the original volume

  Calculate the number of molfow/ j:, siy:becules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How many moleccm9)k ylb5*d.t; ru+g mqax6mules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) moles u3nvf z:lr3p.,    $ \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 5v+rle do6qs9e7s jf+e 8fw), s.1$ \times10^{ -2}m^3$ is filled with air at atmospheric pressure at 20 $^{\circ} $ C. The box is closed and heated to 180 $^{\circ} $ C. What is the net force on each side of the box?    N

  Estimate how many molecules of air are in each 2.0-L breath yriovzdu7 q)2-q sn +gu2e ):0xpsgx4you inhale that were alsun:gv2di- r7op)qux4xysqz) +2 ges0o 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 translational kinetic energy od1lp )f-0b 4gxp64mevop ep/ 9ycowt( f an oxygen molecule at STP(o yg4cp1 mep06lx o be)dptfv/ 9-w4p?    $ \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 tempa-9spm 4uk; ch)qd)z,(i luh herature of about 6000 K. z9kidmu(qc4a) )p hh ls;,-uh   m/s

  By what factor will the rms speed ofcq py tx2 xj 0umhfkh61q6(ztt(3m96h gas molecules increase if the temperature is inc0hqzm9 ( k1x 3cxj ftp2m66htu 6ytqh(reased 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 the5qac-35 f8 jvz min3nj following speeds, given in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, vz5njnj c3qmi5fa-38 and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas a8f -dikjr ru8g :y31gy:w(mknt 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 wh ks i/n)(f 7hm:r,*1ks ;iyfed b69jmni9spohat fact)pfsdir9ymib h7 sh s k9,mke(:fin* 16 /nj;oor does $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is ghsqa; 0u ty4ie : 9dsgz;w0/hniven 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 t oy 6hqfbkt*6*g7ze9b w4t.ilemperature, the ratio of their rms speeds is equal to the inverse ratio of the square rootsk6 iw* qz76t*yeh 94.bgltf ob of their molecular masses.

  What is the rms speed of nitrogen molecules contained in dnxz,8uow,szr* z 6647iod inan 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 lbor o:2ki/u(n9 k.lyoxygen 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 dist 2m1 ,sls 4oo9(rzdfytance between nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular depf.ztc14l8 sn- bw ,mass is 89 u in a living cf-dc1s8.epnz lt,b 4 well 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 n 2omj(3)d rc/k3ptod t4g;acwritten 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 uraniakwnmci;+h- /um, $^{235}$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 pree*hw + k,6rawjssure, 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 pa5n 8w6py k:;dku iv6eressure is 0.01 atm and the temperature is (a) 90 d;5:neyu kw6pia8v k6$^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximatelyt2: dx87 oikjz) if the humidity is 50% on a day when the te7:jzdkxti o 82mperature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water 7/hci cx/ j0oq o 8f2rup5pil;boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particulz; xoi jti. :)6wo6vwoft,/zw-q vv,mar place in the mountains is 0.72 atm, estimate the temperature at which water boils.iivwqtm .ztfv-,w6:o/)z;6x o, ow jv $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of watercd 4w(t1e f ntagrv:0g8,cn +y is 530 Pa and the relative h gw:+4vtt,nncd fr01( ecg a8yumidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the temperaturhfw ,bm t;+xs2t p4ml6e is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressurr/) 3kg vbz6ege cooker if the water is boiling at a 3v rgg/b6)kzetemperature 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 voluh 5fg9q vj77qwwu)x: kme 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 p k9ol,k2nslut+a4p+1l i 3la voint 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 13–4) to diffuse df7ljkpb qy0 q04w6y6a distance of 1q wdjbyf74y p00k6 ql65 $\mu m$ in water at 20$^{\circ} $ C if its concentration varies over that distance from 1 mol/$m^3$ to 0.4 mol/$m^3$ Compare this “speed” to its rms (thermal) speed. The molecular mass of glycine is about 75 u. t $\approx$    s ([color=rgba(0, 0, 0, 0.85)]Round to one decimal places) $v_{diffuse}$    $ \times10^{ -5}$ m/s
$v_{rms}$    m/s

  Oxygen diffuses from the surface of insects to the interior th a/2f51-goe:f abpohv kj+6kzrough tiny tubes cal zeofkvo pf :1-b25/ akg6ha+jled tracheae. An average trachea is about 2 mm long and has cross-sectional area of $ 2\times10^{-9 } m^2$ Assuming the concentration of oxygen inside is half what it is outside in the atmosphere,
(a) show that the concentration of oxygen in the air (assume 21% is oxygen) at 20$^{\circ} $ C is about 8.7 mol/$m^3$ then $\approx$    mol/$m^3$(Round to one decimal places)
(b) calculate the diffusion rate J,    $ \times10^{-11 }$ mol/s
(c) estimate the average time for a molecule to diffuse in. Assume the diffusion constant is $ 1\times10^{-5 } m^2/s$    s

  A precise steel tape+qtc7oxtqpsh; fm;-,en 9 3wl measure has been calibrated at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A precise steel tape measure has been c/)j p5zuit;p7/z evzj/o/qhr cnq 0h, alibrated 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 tempu.qjix5qa biy6:ky:/ q80ax6 y0vhdv erature. How much error will be made in a recipe calling for 300 mL of cool water, if the water and the cup arbv k ya:q.q 65iav/ qx:dhyy0ix8j06ue hot, at 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in a henl( whivq 22eyl90sg5lium gas cylinder is initially 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fract29v5eig0(lynw2ls h qion of the original gas remains in the cylinder?   

  Estimate the number of air molecules in a room of length io0:* ;ktfb( kv ,sie. b*dx9jijjl :d6.5 m, width 3.1 m, and height 2.5 e jjb0dx:t:vii i d.(o9skfl;*j*bk , m. Assume the temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is about one atom pq2 i. 2d9nweo ih;dnh9er $cm^3$ 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-yui;/rdwt/5hk(gk y p s6 g9ieb.er8 using the best available vacuum techniques is about.e5y8s -6/i9kgd/gpk htw eu;(i rybr $10^{-12} N/m^2$ 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 ) xts)nvmo n/n ijy-a4*+oi2p yb 8ca-to full capacity of 5.5 L when 10 m below the surface, to what volume would his lungs expand if he quickly ros 8a )ov/yn i-byp-ms42cixj*+ nat no)e to the surface? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’s :u irqva n-z6mmb7b97l 02kpratmosphere 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? (Becausnq mv96-uzr7kal :7mi 0 bprb2e of this high temperature, the nose of a space vehicle must be made of special materials; indeed, part of it does vaporize, and this is seen as a bright blaze upon reentry.)    K

  The temperature of an ideal gas is inc hoxn m6i7he3+reased from 110$^{\circ} $C to 360$^{\circ} $C while the volume and the number of moles stay constant. By what factor does the pressure change? By what factor does $v_{rms}$ change?$\frac{P_2}{P_1}$ =    $\frac{(v_{rms})_2}{(v_{rms})_1}$ =   

  A house has a volume of 770mivlbg3o. 3yutaz vz. 3uh3 3-l$^2$ (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 surfac,0eizasr - jt3e of the Earth, estimate the totas,j t0aeiz3r -l number of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed ofp(ov.f9 pdjicq 1f) c75a:etp nitrogen molecules contained in a 7.6$-m^3$ volume at 4.2 atm if the total amount of nitrogen is 1800 mol?    m/s

  A standard cylinder of oxygen used in a hospital has ggku;m:l:2bv y auge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pres ;u2vby:gmk:l sure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liqui d.wrt.jprv6 )d 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 t1/my .plefn9ynyb:sri 5x140$^{\circ} $C is 0.68$ \times10^{3 }kg/m^3$ What is the density on a hot day, when the temperature is 38$^{\circ} $C?    kg/$m^3$
What is the percentage change?    %

  If a steel band were to fit snugly around the Earth’s eqsi2m)hws7,t,ryp1 l : gu yb,zuator 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 jar an/(uhg :z u3h(axp iu7t 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 standar1qurkn4jc9 u0 .nb .n( hl7jtjd, 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 fufo +re*vk 8nbcog3- vaxm; 5:illy 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 73fosn/o wt4 p *oyiltrm7+5 fEarth 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 tennis balls thr4j41 w)lqrp a *xjxfe/own vertically upward at it. How many tennis balls per second must rebound from the lid elastic *w xrjj)4xe4palf/1qally, 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 of air from a dej q.dcu2 a.;kmw1l0aspth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the ai0 l 2u..cad;m1qwskjar behaves as a perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressur66apux7wes9 +rir lojcv(./pe in the air on the following two days: pjv6ser ux c.7+9awopr6/il(
(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 a 9u wzdr7ow4u5afe;+it is a solid deep in the Earth where the temperaturu;e f5 aar w9+o7zuwd4e 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 pre;tn9ge 7 +wef0xq+gamssure, the coefficient of volume expansion is equal7+9teg+f qx0 eaw;gnm 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 dehumidi+ w x 2 dpc-/q2n7.zsbt- c;5gufnuoqgfy their cellars to prevent rot and mildew. If the cellar i st7c;/2b+qqupuo wxfg c-n5ndz-g.2n 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