Which has more atoms: 1 kg of iron or 1 k;b b;opvgc)- dg of aluminum? See the periodic table odc g)pb;bo- v;r Appendix B.

Name several properties of materialslg j9yvr;d (bh(xx1u+n8 o2t s that could be exploited to make a thermometuyt ( ljdxr1hx n(8s;2+9bogver.

Which is larger, 1 C 3 j(*p ;jge(mk2t9r wm7yiqgx $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B is,gind0, (kbg +q fabz4 not in thermal equilb0igg+, z( ,k daf4bqnibrium with system C, what can you say about the temperatures of A, B, and C?

A flat bimetallic str-9vlhxs4qz de zj. jhzl4pwl(w d++.: ip consists of aluminum riveted to a strip of iron. When heated, the strip will bend. Which metal will be on the outside of the curve? [Hint: See Table 13–l:v 9.j+szlwq.e h-zh4d( jpwl+z 4dx1.] 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 ofwqv fi*j.b z7 7k*vt1f 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 t1k .r/klqd;b ro control a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch is a glass vessel containing liquid mercury that conducts electricity when it can flow to touch both contact wires. Explain how this device controls the furnace and how it can be set atk1r d kb.q/l;r different temperatures.

Long steam pipes that are fixed at the ends often have a section in the shape o,9g sa bow j6dk:o(;sa1ee3jo f bd3aa9 se6:1ok;,jwjosoe(g a U. Why?

A flat, uniform cylinder of lead fly .nvdn8g3*c ,s:k )juph(fpg oats 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 thermometeri 0q)rocvrc2 ;.u.qs y:kpht/ is first placed in a hot tub of water, the mercury initially desq2r cr h :ou;cq/s.tv k0)y.picends a bit and then rises. Explain.

A glass container may break if one part of it is heated or cooled mowks u*sb ih v4,erb.*i.xpo4-re rapidly than adjacen prbv i.4h**4 wx,i -se.bsoukt parts. Explain.

The principal virtue ov m sv c,p1/mloyf*5 )kkg6c)qf Pyrex glass is that its coefficient of linear expansion is much smaller than that for ordinary glassgc/1 v6 ,p5 vcm*ks )f)qoyklm (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurt+, c uvpdw++date 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 cauqjmv3 vb c2kt9 6 828s::n5 zvdqgjz)nylbk u.se its bottom and top to bulge so badly the can will not stand up. What has 8nqk 8sqgnlc.j: ubt2vdbz3k5)6 :9m2z jyv vhappened?

When a gas is rapidly compressed (say, by pus,o d/yvdc)utsuso**c12 qb)i j+n 6ze hing down a piston), its temperature increases. When a gas expands again)c62c 1t udeind )bj *suo+qs */yov,zst a piston, it cools. Explain these changes in temperature using the kinetic theory, in particular noting what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force on an aluminum sphere submerged in water increoy.( 2z/uvciv ase or decrea (v/oyuczvi 2.se if the temperature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law fop(ecm( i 6y.b l/ ulqpuv55;8,dv bhhsllows from kinetic theory and the relation between average kinetic energy and the absolute temperld(p p,/m.sbcuvbh5l ; v(y 568 ehuqiature.

Explain in words how Gay-Lussac’s law follows from kinetic th5etcbxxh.9hnr -6 s1pq(p j .xeory.

As you go higher in the Earth’s atmosphere,wns w8ok s;xz)ksb ,85 the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed an 8/s wtv4xemk.hi4 y bq9u+p5bobject must have to leave the Earth and never return. The escape w9puq/x h t mkv+4b biye5.84svelocity for the Moon is about one-fifth what it is for the Earth due to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at;;rim g+o7gh gya(9fo,xtq z0 room temperature. What can you infer about the molecular properties of one relative to the o gf;a 9g (mo7z;+h0i ,goytxqrther?

Explain why a hot humid day is far more unci1pe5x8 .+cntyuwq ;lomfortable than a hot dry day at the same w5uet.;ic+n1qp 8xy l temperature.

Is it possible to boil water at room temperature i5 2bnbq ber-15 txgs/n1rv5.yxs1 c r(20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the a09fsrlqm.b0 d .v:pc hir temperature is the same but the humidity is differ 9.fbq .pv0:0 crlhsmdent. Which is more dense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerovw+2lnnkzp/u7l s 4u6us to open the radiator cap of an overheated automobile engine7v2z 6llnp u/kw 4sn+u.

Why does exhaled air appear as ew,2y)ferl2/yy. koj xze ), dvxo7f)a little white cloud in the winter (Fig. 13–28)?

  How many atoms are tng0zs--u rf3 gc e04swhere in a 3.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram b( mvby 93qwcut1i8jh; y63 qigold ring compare to the number in a silver ring of the93yit3ybv w8(i b;juq6cm 1q h same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken h*zf4)hwid 9sto be 68°F. What is this on the Celsius scale?s*h 4f9ihw zd)   $^{\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 136ym617txf dw(i $^{\circ} $F in the Libyan desert and -129 $^{\circ} $F in Antarctica. What are these temperatures on the Celsius scale?high =    $^{\circ} $ C
low =    $^{\circ} $ C

  (a) 15 $^{\circ} $ below zero on the Celsius scale is what Fahrenheit temperature?    $^{\circ} $ F
(b) 15 $^{\circ} $ below zero on the Fahrenheit scale is what Celsius temperature?   $^{\circ} $ C

  In an alcohol-in-glass thermometer, the alcohol column has length 11lz ze 0kf8q 3z/h,lxe,.82 cm at 0.0f30,8q ekz h, lxz/ezl $^{\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 builqo7u)5,oldoe4sso a3 t of slabs 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) is built of wrought iron approximv tyywo. o 8n90*sioj b-0nzl2ately 300 m tall. Estimate how much its height changvyo-8o.*w0 0zb ystlnjio9 n2 es 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, rive7a iyl)j r;q 56gy8mbfr29gfh ts that are larger than the rivet hole are often used and the rivet is cooled (usually in dry ice) before it is placed in the hole. A steel rivet 1.871 cm in diameter is to be placed in a hole 1.86bf9m 8lajqy)i5hyfgr ; 2r76g9 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 a t(ics 6-js3ybz/s:h wt 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 did9 d v /*)yv,u.lwnszlameter. What will be its change in volume if it is heated ,n / s v9ld*vy.zwdlu)from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim w7 (ztmol4rsyp (a2yb2ith 350.0 mL of water at 100.0$^{\circ} $ C. If the temperature decreased to 20.0 $^{\circ} $ C, how much water could be added to the glass?    mL

  It is observed that 55.50 mL of water at :8y )8 xxzbhizs ::dzw20 $^{\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 ring made of5cfe-hvnet( *b,5s kv- yb*ax 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 loa2)b 0 ldbz*b7/d bjwjng, narrow vessel so it can expand in essentially one direction only, show that the effective coefficien*w bjl/)b2j0d b z7abdt of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the;.0d9zabmeg5mey/ mve w1j y, 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 /hdc uqv c;h,9of linear expansionv/cchu;dqh , 9 $\alpha$ 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 soliks1anii t;( k.d, $\beta$ = 3$\alpha$ if the amount of expansion is small. $\beta$ and $\alpha$ are the coefficients of volume and linear expansion, respectively. [Hint: Consider a cubical solid, and neglect very small quantities. See also Problem 18 and Fig. 13–30.]

  The pendulum in a grandfather clock is made of braat*ny p mjl:ygq18 9 y8n.z:f+u*ereyss and keeps perfect time at 17 gnyeyy*m :n1 :8e+ zflpuja8t 9r.*qy$^{\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 0.140 mm. Tt6 mk,xjpin5m-l:n3 v1rz*d c he bulb has a volutv-zdjn,nx3lp cmm 1i6:r* 5 kme 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 rotating ttic8e qcqov7.w50un .w ng9 5about its axle on frictionn.8qoq nti5.5 ucgw9e 0w c7vtless 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 much stress e 9yu) tsg ku8dl:6ue.is required to keep it at this length if the temperature incretd6se8yul e :g)u.uk9ases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-sectional area 0.041y*9jj 7malsbdf /j)bdre di9 h.w4 mn+ 8)q7ul$m^2$ is rigidly connected to two vertical steel girders. If the beam was installed when the temperature was 30$^{\circ} $ C, what stress is developed in the beam when the temperature drops to -30 $^{\circ} $ C (b) Is the ultimate strength of the steel exceeded? (c) What stress is developed if the beam is concrete and has a cross-sectional area of 0.13$m^2$ Will it fracture?

  A barrel of diameter 134.122 cm at ramjcp 1v0.8 3 a7 ybbcoci,t/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: ykxi o5 -3bhnp hrz)n g-i3/7d
(a) 86$^{\circ} $ C,    K
(b) 78$^{\circ} $F,    K
(c) -100$^{\circ} $C    K
(d) 5500°C,    K
(e) -459$^{\circ} $F    K

  Absolute zero is what temperature on the Fahrenheit scale-iobp)fi b, a62f4fuk?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and v)xlc al(8fi::j6 hnsSun 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 atmospheg*, ++tqb us fi,ghsuv0vm ,u2ric pressure and a temperature of abou+2bss,gu,+ tgmfh v,uqvui 0*t 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 thfyvsy td k2a2r:5,a 6h szpyznig(-*5e ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of niti/y7* 6 9gu3xyd3vzg13i pozq i)g.qyg(dqqqrogen ($N_2$) 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 cn)qnm:.mga:g ontains 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 o ik1o1apy) dp.1d1eigas 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 gas eg89-dx1z gud/.dnya0h 7, rqbt x xu)at 38 n a y/8ggtheqdbz- ux)x,.u 91d07rdx5 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg of 8dkd urvt;9nmxe*8f) $O_2$ 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 bd9g xihc 4t;*evpot;l+(k+cguoyant lift by heating the air inside the balloon, which makes it less dense than the air outside. Suppose thecv 4; ;eg*9+t(chlt+xdog k ip volume of a balloon is 1800 $m^3$ and the required lift is 2700 N (rough estimate of the weight of the equipment and passenger). Calculate the temperature of the air inside the balloon which will produce the required lift. Assume that the outside air temperature is 0 $^{\circ} $ C and that air is an ideal gas under these conditions. What factors limit the maximum altitude attainable by this method for a given load? (Neglect variables like wind.) $\approx$    $^{\circ} $ C(Round to the nearest integer)

  A tire is filled with air at 15kfqf l +ml;v9) $^{\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 s2wi pvb k)l87$^{\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 sea level and x rex3e3s2p/j 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 ofl v 80 pev-if4lt+kl-v molecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How many mohsmmprm//48agbl +e2uqxz zbx *5r)rv( /e ;blecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) moles,s wao y0r;m)q)    $ \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(fxfg aigj3+xmfss*8* m *x:l e 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 molecules of air are in each 2.0-L breath you inhr 1etw5n )f my+m+rus,ale that were also in the last breath Galileo took. [Hint: Assume the atmosphere is about 10 km high +5e+,yutr 1mnmf)s rwand of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of an oxygen molecawz;e(h5m pp. ule at STez.(;p5 wm pahP?    $ \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 Sx1z-k.rzaq0k g i(qf2xr . :ehun at a temperature of about 601h .:2iqerfk-g.(zqxk x0 zar00 K.    m/s

  By what factor will the rms speed of gas molecules increase dbz d1(wx*5q7v8tec g 1p5cse if the temperature is increa 5pedv w1sc( teq5cb71g*z8xd sed 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 havo*cm,-o ic c fr9y8-koe the following speeds, given in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, o-if-oco,9 k8cymcr*7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of mole . i0kdis/lxs4cules in a gas at 20.0 $^{\circ} $ C is to be increased by 1.0%. To what temperature must it be raised?    $^{\circ} $ C

  If the pressure of a gas is doubled while ih2pkufjpij j,o5 t.) 6z/ m+b*isr qg-ts volume is held constant, by what factor z5j/)g,i.mjr-hjpk qu*sop2tf +b 6idoes $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is giv//dc/+l owc8gnc:bsx4jm/g xen 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 gase d aqbmbp11/*r+)gld+1mzk 0rgkzr08bd ov+ks at the same temperature, the ratio of their rms speeds is equal to the inverse ratio of the square roots of their molecular ma+z prabbr+d1o q/*0d18)kb gklgrvkzmdm01+ sses.

  What is the rms speed of nitrogen molecules containe7twkj 4/eezlb .*. hg-okm,apd 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 speed3.nv p, e5bnlo of an oxygen molecule at 0 $^{\circ} $ C    m/s
(b) determine how many times per second it would move back and forth across a 7.0-m-long room on the average, assuming it made very few collisions with other molecules.    round trips per sec

  What is the average distance betwypcf)ruqd xf*5 jiu8f;u5:6 l*d ep)x een nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms s0klqbxz2vc+ 4r 9*grmpeed of an amino acid whose molecular mass is 89 u in a living cell at 3l9vx+ kqr *4z0mcb2rg7 $^{\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 4 :yz-ieatl0tca94 km 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 urani:btwl4 ta2y p,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 pressure, in what phas:rqlf 4,g- 8k8rcvkmfes 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 amf mnlvgg-1.5yy u.3rp0 e ctu.) g;9sddfv9ttm and the temperature is (a) 9t ml9;n pe yu s. yfd1tgu0dg.-vrm. 5cf3g)v90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity is 50% r)noh y 84lpi+b.28 wi9blslt on a day when the temperature i9lb8 i+r) 4b hlo. wt8syl2ipns 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water boils at 13d*xbbavh rd9z: g+ c90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a parti6 tqq10 hnelkq-s:u) mcular place in the mountains is 0.72 atm, estimate the-)q: n 06hek1umq tslq temperature at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressur0 fjfls ym8ie ,9mho t4u(g:n(e of water is 530 Pa and the renjs4luhtff, e8myo0(g :9( imlative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day wh kyc3j2x*gkwfhmfb7 7,oar 5xgb3i :;o):dhpen the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cooker if the water isl2 j8s+ywtd t 7vy:l)s boiling at a temperaturej:y8t )y+t s wd2ls7vl 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 680q+t1gyukk )y0-45hod0er y pz tz/f;l$m^3$ at 25 $^{\circ} $ C is 80%, what mass of water can still evaporate from an open pan?    kg

  Air that is at its de+j8d( iigxl4h w point of 5 $^{\circ} $ C is drawn into a building where it is heated to 25. What will be the relative humidity at this temperature? Assume constant pressure of 1.0 atm. Take into account the expansion of the air.    %

  Estimate the time needed for a glycine molecule (see Table 13–4) to diffuse :snjjf,*d0 - s-bg5syvr yfm(a distanfjbj(smgf*y- ,sds50-v :yr nce 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 of insects to the interior throug:ntq+;fqwg )t h tiny tubes called tracheae. An average trachea is about 2 mm long and has cross-sectional wnft:q +tg ;)qarea 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 calir;gz- n55ankzbrated 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 calibrate 9nv5(t0rf .ywth)uemo9dc0 kd 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 temperatusgzjp 51j4ew k 9(jp-;kw+ fbxre. How much error will be made +gwzwx49be(f pk1j-s5kj j; pin a recipe calling 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 cylinder is initially 28 atm. After maxc+*r,r 5aqk5 ajv1ajfl (eg,ny balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of tjc rrea l+,5(a gfjkvxq 1a*5,he original gas remains in the cylinder?   

  Estimate the number of air moleculesgd7bl93rqp / i in a room of length 6.5 m, width 3.1 m, and height 29lpi/3d rg7bq .5 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 abou 9b0 zlr+t;jwe3 s;-eexiz:q at one atom per $cm^3$ mainly hydrogen atoms, and the temperature is about 2.7 K. Calculate the rms speed of these hydrogen atoms, and the pressure (in atmospheres).$v_{rms}$ =    m/s    $ \times10^{-22 }$ atm

  The lowest pressure attainable using the best available vacuum technique)(ueygcqwn; s n y 8;n)yllu+)s is about nwlly(;)uc;8qnnyu)yg+ )se $10^{-12} N/m^2$ 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 5.5s6:38e wq9 6l5i, cegkpezd4)rhsnnh L when 10 m below the suz,ewh5sc648:sni ek l 6dr9 )ghqpne3rface, to what volume would his lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmosphere at apk o meg,.en cl( y/x .1oo:2wn;7sdqm speed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this speed correspond to what temperature? 1opd/7;c,s.yq: l.og(x mn we2 mnkoe(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 gas is increased from 110cz 0ytc;: -;+k:k b j4lvqlyyj$^{\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 7705 fsf:xw(nl8-ohc .af m$^2$ (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 9m)wdzd*4n br at the surface of the Earth, estimate the total number of air molecules in the Earth’s94d *w)rzdn mb atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitroo gqklk-; y-s;gen 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 gauge pressure = 2000 psi (artn:)cg vc 4;13,800 kPa) and at T = 2a: nccvt g4r;)59K How long will the cylinder last 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 tg-xzkh .e6 xso/uq:+7ig.e vliquid 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 uq. 2 pn8- :k-tnhbfia0$^{\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 tfbp 10n3wxftw4, qs )khe Earth’s equator at 25$^{\circ} $C, but then was heated to 45$^{\circ} $C, how high above the Earth would the band be (assume equal everywhere)?    m

  A brass lid screws tightly onto a glass jar at 2b6)vymtkjg5a f mrk yd33 4()r0$^{\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 th dvki4 +/yvvdt:lg/g8e 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 pig5iw*5ji kf.ressure 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 Eart+f-zz 4lu 0nnmh 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 l/ 3g k 4(mks mr pg.57wre)h/mg:ntxmtid is suspended against gravity by tennis balls thrown vertically upward at it. How many tennis balls per second must reg :kwm5 me 34rng)k /ms7.tgx mthpr(/bound 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 3.0:n( nx io:/h6bh/mqj i0-cm-diameter (spherical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the air behaves as a perfect gas. How large is the bubble when it reache nj: :/xhio/6nhmbi(q s the surface?    cm

  Calculate the total water vapor pressure in the air on the followinf;c *feu iy4jdo(q( 3kg two days: dfi * j34(okufey(c;q
(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 yj6y8 p6,7 vnh.n1*eblqcpyv when it is a soln y,*pj.lvhcyye bnqv 786p6 1id deep 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 gas at constant ft9ml- (ptp p.pressure, the co9pmf -lpt .tp(efficient of volume expansion is equal to $\beta$ = 1/T where T is the temperature in kelvins. Compare to Table 13–1 for gases at T = 293K (b) Show that the bulk modulus (Section 9–5) for an ideal gas held at constant temperature is B = P where P is the pressure.

  In humid climates, people constantly dehumidifyzxl 0s4 :pwb2a their cellars to prevent rot and m:02 xsbzpwl4 aildew. 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